Hey guys,

Just thought I would do testing on the Air dog 80 I received about 3 weeks ago.

I will tell you up front I am only bench testing at the current time. I wanted to get some information on the bench before I installed the unit on the truck.

So here is what I did/know.

I started with 3 gallons of diesel fuel in a 5 gallon bucket. I used a fully charged Optima battery along with a 10 amp battery charger for a power source. I used 1/2 clear tubing on the engine feed line and the filler neck return line. I used the provided blue fuel line on the supply side.

So by using the clear tube, I was able to see what the fuel was doing including air bubbles.

The Airdog comes with a indicator light which is activated by a hobbs pressure switch. The purpose of this light is to let you know if your system needs a fuel filter change or has other problems. The light should be OFF during normal operations. If the light comes on, this signals that your output pressure is lower than desired operating pressures.

So with that in mind, I had to crimp the output line to the engine down with vice grips untill the light went OFF. This signifys the pump is working within design specs. It is at the very lower limit of the specs but never the less you must make the light go OFF, or your test are worthless.

So here it is, with the engine supply line crimped just enough to make the indicator light go OFF or 4.5 PSI.

11:43 AM 54.1 F ambient 53 F fuel temparature.
12:11 PM 55.8 F ambient 56 F fuel temparature.
12:42 PM 57.9 F ambient 62 F fuel temparature.

So in 1 hour the ambient temparature rised 4 F and the fuel temparature rised 9 F. A rise of 5 F in 1 hour.

The motor was drawing 2.5 Amps. The back of the pump motor heated up to 89 F.

During this time the output to the engine was 133 GPH @ 4.5 PSI. It took 27 seconds to fill a 1 gallon jug.

The return amount to the filler neck was 5.63 GPH. A very small amount causing no ariation what so ever.

So very little fuel was going to the return neck and most all of the fuel was going to the engine.

During this time I purposely ariated the fuel as much as possible. I positoned the engine line so that it was above the fuel by about 3 ". This caused the fuel to foam excessivley. I then rocked the bucket back and forth causing the foamy top to be churned under. The air separator did an amazing job of sending the air bubbles to the return filler neck and sending bubble free fuel to the engine side. I could not see any bubbles at all going to the engine. During this test the unit was in a mode where the regulator ball was completly seated. The only fuel going to the filler neck was getting there through the bypass port. As the pressure increases, more and more fuel will go to the filler neck, rather than the engine. This increased flow to the filler neck will change the test results.

These are some of my inital test. My next plan is to conduct the exact same experiments at 9.0 PSI.




My ultiment goal is to get this unit on the truck, identify any possible operating problems and attempt to design an affordable fix if there are any problems. We shall see over the next week.

So here is round #2. Same as above except the pressure was set at 9PSI.

I chose 9 PSI because this is when the built in regulator ball is set to open. At 9PSI the flow to the filler neck will increase to 28 GPH.

9 PSI.
102 GPH. 35 seconds to fill 1 gallon jug.
Filler neck return flow 28 GPH.

4:32 PM 68.7 F ambient 67.9 F fuel
4:47 PM 69.3 F ambient 69.9 F fuel
5:05 PM 69.3 F ambient 72.3 F fuel

So the ambient temperature increased .6 F and the fuel temparature increased 4.5 F

The electric motor only needed 3.0 Amps and the motor casing was 90 F.

I did close off the feed line to the engine and let all of the fuel go to the return filler neck. It creates a swirl that ariates the fuel significantly. The air separator kept up with this air and only sent clean fuel to the engine. The bubbly fuel went back to the filler neck.

During the 9 PSI operation the filler neck retun flow of 28 GPH was not enough flow to ariate the fuel.

So it appears the only time the fuel tank will suffer extra ariation is at very low engine demand situations.

The only time the air separator sent air bubbles to the engine supply was when I drained the 3 gallons of fuel empty. The pickup tube sucked dry.The indicator light came on at this time to indicate it was no longer working correctly.

My next action will be to install the air dog 80 on the truck and adjust the provided spring/ball regulator to acheive a max of 6 PSI at the engine during idle. This is where I want the truck to be as far as fuel pressure. I will test the truck with 1/4 fuel tank in all conditions. If there is problems, I will let you know.

I rate these tests right along side with wet dreams. Put the stupid pump on the truck with a Trippin pick up. Your bubble test has no value because it can not simulate how the return fuel travels back in the bucket in our trucks. Go buy a bucket for 400 bucks, test it, ruin it, then go buy another. Formulating opinions from brochures are usually disastrous. Put the pump on. :rolleyes:

Mike don't you have a tranny cooler to be working on?

I am suprised Steve let you down off his lap.

Bronco

Do you have any original ideas based on real world testing or do you always rely on reading from manuf. sheets? Answer this question. Have you ever installed a fuel pump on any Duramax truck? Fess up. I have friends in Colorado that know you so don't fib. How can you make all these so called technical statements when you have never seen a pickup unit in our tanks? You constantly refer to DIESEL 5s fuel pump problem as an isolated incident. How did you come about that diagnosis? I guess it did not jive with the brochures that you use for your technical basis. I will ignore that childish remark about sitting on someones lap. Seems when you can not come up with a real technical answer you revert to the little boy stuff.
mike

Bronco,

i do think you need a complete OEM pickup to do the testing any justice.. unless you don't plan on using the OEM pickup in your truck. don't forget factory line sizes, the relative heights of the tank to the filter, etc. the more constants from our trucks you change, the less valid the data will be.

I did close off the feed line to the engine and let all of the fuel go to the return filler neck. It creates a swirl that ariates the fuel significantly. The air separator kept up with this air and only sent clean fuel to the engine. The bubbly fuel went back to the filler neck.
Did you just retype this from some advertiseing? If you read it do you see anything wrong with it?

Diesel tech sometimes your own thorougness blinds you. You are so quick to point out little discrepancies in what people write. Anyone with a clue knows what I was trying to say.

For your benifit, I will explain it. I closed off the feed to the engine. This diverted all fuel to the return filler neck. It swirled and caused surface ariation. I grabed the edge of the bucket and rocked it back and forth. This churned the surface ariation down into the fuel. Now we were dealing with some ariated fuel.

Now here is the little technical detail you tried to discredit me on that most people automatically adjust and go on with the findings.

Are you ready?

Here it is.

AS SOON AS I LET THE FUEL GO BACK TO THE ENGINE THE AIR SEPARATOR DID ITS JOB. IT PICKED UP ARIATED FUEL AND SENT ONLY CLEAN BUBBLE FREE FUEL TO THE ENGINE SUPPLY SIDE. THE BUBBLES WENT RIGHT BACK TO THE FILLER NECK. I COULD SEE THIS IN THE CLEAR HOSES.


So basically in another thread you questioned what happens to fuel that is constantly recirculated with these style of pumps. Now you know what I found. The air separator can cause foam in some situations but it takes it right back out. It also adds no appreciable heat to the fuel. The return from the engine adds more heat than these style pumps.

So instead of being a butwad, stop and learn something for once.



And to the previous post. In the very first line of my first post, I said this was a BENCH TEST ONLY!

I am completly aware that I was not duplicating actual truck conditions. You will never, ever be able to duplicate what the injectors are using, and the pump is returning. The amounts will constantly change based on what the engine load/status is.

Over a year ago HDMAX and myself had a little discussion about how the FASS and Preporator were different. We came to the conclusion that riding around in the back of a truck with open 5 gallon buckets of diesel fuel was not a very smart idea. Now a guy with a chassis dyno could do a more accurate test but it would still not be the same as driving around and ariating fuel.

Alls I was doing was establishing some baseline facts and figures for my own benifit later.

I was sharing it with those that were interested. If you dont think it is of any value, good for you. Read/post in somebody elses thread.

For those of you that do care, I will install this Wendsday. Factory pickup, factory bucket. Adjust pressure to 6 PSI @ Idle and see what happens.

Diesel tech sometimes your own thorougness blinds you. That's because Mike L is sitting on his lap... remember?:ro)

I was thinking more of a little dog sitting in dadys lap. A.K.A. lapdog.

There is a few of the those yappy little ankle biters running around here.

Bronco

What you seem to forget is for over a year now you have been stating the Preporator/FASS is the answer to all our prayers but in that same years time you have not managed to install anything on your truck and test while others have. Guess what there are problems! So when you type garbage that comes from advertising hype I will call you on it
So we've looked into what's going on in the real world not just in our heads and from advertising hype. Truth is you continue to play on the bench with cold fuel and we will continue to test in the real world where the fuel is heated by the factory return system and the so called air removal only can work if the return is active on the FASS/Preporator. Then maybe you will see what we do in the real world! Then when you add some power such that the problem becomes the lack of fuel and the return closes do to high demand you've got nothing better than just a pump like any other pump on the market today. For those with a stock truck the FASS/Preporator is a waste of time just as any pump is but for those who are raising the HP where a pump is needed they are still no better than a pump. Is that plain and simple enough for you to understand.

You can try and make it look any way you want. You always do.


Funny thing is, outside of your small little world, there are people using these pumps everday with all fuel levels. Members from this site and since there is only 10,000+ there are also nonmembers using these pumps. So I am trying to pinpont why some have problems and some do not. Can you deal with that?

I am going about it my own way and I will post what I find. Even if nobody reads it or nobody believes it, I still have the right to do my own testing and post my own results. This is still America isn't it?

I have ZERO finacial interest at stake. No soon to be released system. No reputaion at stake. No vendor loyalty. I just do this for fun because I own and drive one vehicle daily. A Duramax powered Chevy. Can you deal with that?

I am going about it my own way and I will post what I find.
That would be great! Just post what you find from getting up and doing some testing not reading advertising hype and assuming. If and when you ever do that I would have no problem with it and then we could event compare test results. So now its time to put up or shut up.

That would be great! Just post what you find from getting up and doing some testing not reading advertising hype and assuming. If and when you ever do that I would have no problem with it and then we could event compare test results. So now its time to put up or shut up.I'll tell you what impresses me, is the fact diesel tech was able to type these last few posts without errors while mike L was sitting on his lap!:badidea:

That would be great! Just post what you find from getting up and doing some testing not reading advertising hype and assuming. If and when you ever do that I would have no problem with it and then we could event compare test results. So now its time to put up or shut up.
Steve in all your great wisdom I am suprised you have never designed fuel rails with a larger capacity.



You know without very thorough accurate testing it is wrong to just get up and badmouth somebody eleses product. I spent alot of time researching these air separators. They do separate air. One thing I learned in all my research is they were designed for engines not quite as technoligcally advanced. as the mighty Dmax.So no HPCR, no vacum pump/high pump all in one.They also have to be sized correctly. You points about how they operate is valid. But if they are sized correctly the do work as advertised. Problem is, you have a pump up at the front of the train that sucks like a mofo, that will reduce pressure on any pumps output. You also have a leak called a factory return line that is infinetly variable, hard to keep up with at times.

So once apon a time, an air separator being the only low pressure fuel supply device, and the only return path, sized correctly, applied to an engine that did not have such an incredibly wide range of fuel demands ( Extreme programed Duramax) and with a bucket that also compouded the problems, these things do work. Thats why they are being sold and do work.

I understand they have there limitations when placed into a Durmax without any other mechanical fuel system mods. My goal has been to find a solution rather than just throw it out the window and start over. It's hard to beat the lift pump, air separator, water strainer and fuel filter all in one concept.

So ask yourself this, does you Extreeme work on every truck in every condition without a fuel mod? No bursting. No excessive rail ressure pressure drop? So sometimes we all need a little help. My goal this entire time has been to pinpoint the problems and see if there was an easy work around.

If you want to keep saying that I am lazy then let me ask you this, where is the tranny cooler, where is the PL3? Where is the speed limit removal only tool? Answer-Sometime products are not cost effective. Same as my testing. Any real engineer knows that to prove what is happenig with these fuel systems on our trucks beyond ANY REASONABLE DOUBT that it takes alot of time and money. Two things which I have no extra.

If you wanna say allls I do is copy advertisements then look in the mirror. I am not the one being accused of copying some other corporations literature then sending it out to my distributors. How about you?

Steve we can go tid for tad untill the end of the world. However there are beter ways to go about this. Try to work as a community here. We all bring different resources and different skill sets to the table. We all have different training and job experinece. There is not one of us here that has all of the answers.



Time to go :grd: !

Steve in all your great wisdom I am suprised you have never designed fuel rails with a larger capacity.

You know without very thorough accurate testing it is wrong to just get up and badmouth somebody eleses product. I spent alot of time researching these air separators. They do separate air. One thing I learned in all my research is they were designed for engines not quite as technoligcally advanced. as the mighty Dmax.So no HPCR, no vacum pump/high pump all in one.They also have to be sized correctly. You points about how they operate is valid. But if they are sized correctly the do work as advertised. Problem is, you have a pump up at the front of the train that sucks like a mofo, that will reduce pressure on any pumps output. You also have a leak called a factory return line that is infinetly variable, hard to keep up with at times.

So once apon a time, an air separator being the only low pressure fuel supply device, and the only return path, sized correctly, applied to an engine that did not have such an incredibly wide range of fuel demands ( Extreme programed Duramax) and with a bucket that also compouded the problems, these things do work. Thats why they are being sold and do work.

I understand they have there limitations when placed into a Durmax without any other mechanical fuel system mods. My goal has been to find a solution rather than just throw it out the window and start over. It's hard to beat the lift pump, air separator, water strainer and fuel filter all in one concept.

So ask yourself this, does you Extreeme work on every truck in every condition without a fuel mod? No bursting. No excessive rail ressure pressure drop? So sometimes we all need a little help. My goal this entire time has been to pinpoint the problems and see if there was an easy work around.

If you want to keep saying that I am lazy then let me ask you this, where is the tranny cooler, where is the PL3? Where is the speed limit removal only tool? Answer-Sometime products are not cost effective. Same as my testing. Any real engineer knows that to prove what is happenig with these fuel systems on our trucks beyond ANY REASONABLE DOUBT that it takes alot of time and money. Two things which I have no extra.

If you wanna say allls I do is copy advertisements then look in the mirror. I am not the one being accused of copying some other corporations literature then sending it out to my distributors. How about you?

Steve we can go tid for tad untill the end of the world. However there are beter ways to go about this. Try to work as a community here. We all bring different resources and different skill sets to the table. We all have different training and job experinece. There is not one of us here that has all of the answers.



Time to go :grd: !
So how much did you pay for your Airdog, also how much did you pay for your FASS? There is no reason to design fuel rails with larger capacity at this time since the one's we have are just fine. Your comment about sizing correctly is a key thing that has not been done by either of the FASS or Preporator, all models supply way to much at low load and not enough under high load, this has been proven time and time again. As far as the Xtreme goes YES, it works as advertised in every truck and we do not hide the fact that fuel system modifications are needed, as a matter of fact we are the ones that discovered the issue in the first place and brought it out to the members long before you start telling everyone the FASS/Preporator was the answer! I do not have to say your lazy your own actions speak for themselves. As far as copying advertisement I have no idea of what your talking about, we make no claims as to air removal so what's to copy, a pump is a pump so I guess in that case every pump supplier has copied from every pump supplier. It's our electronics that make a difference, I guess that why Charlie from Preporator has asked me if they can buy them from us! If you want to work as a community then you would have to first do some work on the project not sit there and report advertising hype over and over again. Take your truck and do some real testing, yes it takes time and money to do and when you resolve the problems then you have the right to sell or give away the solution, but until you do some testing your just running at the mouth.

Time to go :grd: says it all!

Diesel Tech, do you have a lift pump in development?

So for those of you that have ever thought about dropping your fuel tank.

Make sure you have the proper fuel line removal tools. The 1/2 " line from the tank has a deep fitting and the standard plastic fuel line removal tools from the auto stre do not work. You will spend all of your time fabbing a removal tool like I did.

Raise your truck off the ground so you have some working room. Put a jack under your fuel tank. Remove the 1/2" and the 3/8" fuel lines from the cooler and the front of the tank. Remove the cooler via 3, 12MM bolts. Remove the tank straps via 2, 15 MM bolts.

Drop the tank far enough to get at the electrical connection. Remove it. Now remove the rubber filler neck. I chose to unhook mine up at the filler neck where you put the fuel in. It takes 1, 8 MM socket to loosen the hose calmp.

Conitnue to lower the fuel tank. You will have to manualy feed the filler neck tube over the frame rail. It gets kinda tricky and the more empy your fuel tank is the easier it will be.

The first discovery I made was that my filler neck is not as it appears. On the outside it looks just like a radiator hose or standard rubber gas tank filler tube. But the suprise was that inside of the filler neck was a smaller sleeve. It was just like the spicket on a portable 5 gallon red gas jub. It was that cheap plastice with the little ribs in it for the bends. Just like a red gas tank nozzle. That inner sleeve is actually attached up at the gas cap. The bottom end is right at the top of the fuel tank. So from yor gas cap to your tank is an inner sleeve.

So during the install instructions of the FASS/Prep they recomend cutting your rubber fille neck and inserting there stove pipe device. I see this as a problem becasue you will cut the inner sleeve, Then reatching the inner sleeve would be impossible. This cut inner sleeve in your filler neck would also cause problems with fueling and foaming.

So to just cut right into your rubber filler neck is a mistake. You must address the inner sleeve.



So the next step is tearing into the bulkhead. I have already done some work there but I will post later. Just wanted to get this fuel tank removal written down before I forgot.

So once you get the tank out, put some palstic over the filler neck and use the hose clamp to secure it. Also cover the bulk head supply and return fittings. I then used a water hose to wash off the enourmous amount of gravel and dirt that was on the top of my tank. Next onto compressed air. Dryed off nicely.

The bulkehead has a standard lock down ring that needs to be turned about 1/2 " to free up the buukhead. Please note there is a small black plastic lock tab. This needs to be pushed aside before trying to break the lock ring loose.

Well the unit comes out as one separate piece. The fuel float gauge, the bucket, the wires, the pickup tubes and everything else is all one device.

The bucket holds 2 cups or 16 OZ of fuel. The hole in the bottom is 3/8 " in diamater and has a rubber flapper valve that lets fuel in, but drops shut when there is no fuel under it. The entire bucket rides on 3 metal rods that are spring loaded. This does allow the bucket to move up and down but the further you move it up, the tighter those springs get. So the first 2-3 inches of travel are under very little spring load but after that it gets very hard to raise however it can move 6" upwards. The fuel hoses are the ribbed flex type and cause no obstructin to this up and down movement. Neither do the fuel sending wires.

If the bottom inlet valve were to become uncovered you only have 16 OZ. of fuel to use. If the flapper stays covered you have 2 cups plus the 3/8" inlet of usefull fuel. If your tank is 1/2 full or better fuel will just come right down in from the top giving you an unlimited supply of fuel.


I have not had time to come to any useful conclusions about all of the bucket purposes and funtions other than the fact that it is a technical little buger. Gm put a lot of energy into making it what it is. It might be as simple as it floats up and down while the flapper on the bottom grabs fuel for the pickup tube?

The inner sleeve that Bronco has talked about is the filler hose. The outer Rubber hose is the vent for the tank. The way it works when filling the tank is fuel runs through the inner sleeve filling the tank and the fumes vent back up the outer rubber hose to the filler neck. So what the FASS and Preporator have you do is to cut the vent hose and return the fuel through the vent side, not a good idea in my mind. If you cut (as Bronco has now found out) the way they say to and cut the inner tube you will play hell getting the piece out of the tank and have screwed up the filler neck. This is different on the LLY applications as they have a external vent line.

I have not had time to come to any useful conclusions about all of the bucket purposes and funtions other than the fact that it is a technical little buger. Gm put a lot of energy into making it what it is. It might be as simple as it floats up and down while the flapper on the bottom grabs fuel for the pickup tube?
The springs are there so that the sender will follow the tank as it expands and contracts with the fuel load and weather conditions. This keeps the pickup as close as possible to the bottom of the tank. Take some time and follow out how GM returns the fuel into the bucket as that is very important to how the overall unit works.

So I had a chance to look at the factory bucket a little closer. It is a 2 part system. The outer shell comes off via 2 side clips at the top. You will need two very small flat blade drivers to get the outside shell off without breaking it.

The inside section consist of the pickup tube which is connected to a egg shapped vessel with a strainer on the bottom. The strainer has about 800 1/32" holes.

So back to the outside section. The outside looks just like an empty cup. The only catch is there is the previously mentioned oneway flapper at the bottom and also a log with 3 tubes sticking straight up out of it. The factory return line feeds the first tube from the top flowing downwards. The fuel travels down and then takes a 90 degree turn into a small log if you will. The second stack is shorter then the third stack and the second stack appears to have a plastic cross hatch about half way down the tube. The third tube is the largest and appears to have no dohickys inside of it. There is also a small hole in the bottom of this log that has no door or closing device and will dump fuel outside of the bucket directly next to the oneway flapper inlet valve.

So I placed a clear plastic tube on the return stack. I then placed the bucket into my fuel tank. The fuel level in my tank came up about half way up on the bucket. i had a funnel that fit the other end of my clear tube. I used a gas can to fill the funnel. Gravity fed the fuel down into the return portion of the bucket. I purposely shook the hellout of the fuel can and also made sure there were interuptions in the return fuel supply. Here is what I noticed. The larger bubbles of air and the passages of air interruption came out the top of the third stack. The very tinys bubbles floated up from the bottom on the outside of the bucket out of the hole in the top of the log.

So basically this design attempts to insures that all returned fuel via factory return line will be fed in close proximity of the oneway flapper valve. This fuel will also be free of any large air pockets or visible air bubbles.

So basically this design attempts to insures that all returned fuel via factory return line will be fed in close proximity of the oneway flapper valve. This fuel will also be free of any large air pockets or visible air bubbles.Bingo, it's an air separator that works very well and keeps the return fuel as close as possible to the pickup. It also keeps air from forming by dropping return fuel through the vent line into the air and hitting the fuel in the tank. This is the proper way to return fuel into the tank not as the FASS and Preporator do it! This method removes the air every bit as good as the FASS or Preporator. Why create air and fumes in the tank when it is not necessary let alone detrimental to performance. Also any fuel that goes into the secondard tubes and comes up as the air bubbles break up will be right into the bucket air free!

Also any fuel that goes into the secondard tubes and comes up as the air bubbles break up will be right into the bucket air free!
I just was out playing with a small fishtank pump. I hooked it to the retutrn line. Do you have an opinion on what happens to the fuel coming out of the third tube if too much return pressure is generated?

I noticed the fuel shoots up like a small fountain and lands back on the top of the bucket. I suppose the landing spot of the fuel would have to do with the current gforce as well. Maybe I am over thinking it?

On a side note, the more I poke around the more I always want to keep my fuel tank full. This driving below the top of the basket is for the birds. They try to make it work but nothing is as good as having a few feet of fuel sitting on top of your pickup.

Bingo, it's an air separator that works very well and keeps the return fuel as close as possible to the pickup.
Dieseltech I agree the factory has done everything they can to keep the fuel free of foam and excessive agitaion/ariation. They have also done everything they can to insure the pickup itself is always sucking bubble free foam free fuel with no interruptions. This we agree apon.



One thing I learned about the air separators is that they can actauly take fuel that is comeplety settled and squeeze a little air out of it. Diesel fuel holds air at a molecular level. So the air separator squeezes the fuel and forces the air out of it. If you give it a place to go the squeezed fuel will be cleaner and have less air in it then normal #2. So they do have a machine that works.

Just visualize the FASS or 135A on a very large vehicle with a large fuel tank of 60 gallons or more. The return fuel is hitting the top of the surface nowhere close to the pickup on the bottom. So in that type of application it has benifit.

I think what we are running into on our trucks is that the fuel tank is just so small. There is no good place to return large amounts of fuel. The factory bucket is also not capable of allowing large amounts of fuel into it to feed the demand of a large pump.

I calculated that bottom flapper valve to be equivalent to a 3/8" fuel line with little or no pressure on it. So basically when below 1/2 tank you have 16 OZ of fuel, 3/8" inlet and whatever other fuel is in your fuel line and filters. That is it.

I could see any long duration high HP demand being a real problem with the factory basket when below 1/2 tank. What do you think?

I think you need to better go check the flapper valve a little more, it's not that big after you disassemble it. I don't believe that the FASS or Preporator can remove air at the molecular level. If you look at any real lab equipment for removing air it takes much longer to get the air out, than the fuel is present for in a FASS or Preporator, the fuel passes just too fast in these units and to reduce the flow rate means they will not support the engine requirements. I have also been told that the unit Preporator had tested for air removal is not the unit they now produce so who knows what they do for sure. There are much better ways to return the fuel into the tank but it cost a little more than a cheap tee piece that is supplied in these kits.

There is a problem with low fuel levels and I believe we have a way to solve as much of it as possible but I'm not going there. Look what happens when you get up and do some of the work that we have done, you learn much more than the advertising hype will ever tell you. The next task is to start to determine the flow rates needed to supply the system and look at the time required to remove air from the fuel and I think after that you might understand what we have already done and where I'm coming from.

Bronco
Congratulations on your work. Can you now see why the 2 pumps in question do not get along with the Trippen pickup?

Yeah the Trippin pickup allows one of these gear drive pumps to suck even more fuel than they already do. So then you are able to empty the basket that much quicker.

I don't believe that the FASS or Preporator can remove air at the molecular level. If you look at any real lab equipment for removing air it takes much longer to get the air out, than the fuel is present for in a FASS or Preporator, the fuel passes just too fast in these units and to reduce the flow rate means they will not support the engine requirements.
When I had the 80 running with clear hoses, you could see tiny air bubbles going out the return line while the engine feed line did not have any. You have to have clear tube and a light source, but the bubbles are there.

So maybe it is trickery but I saw what I saw.

I worked in a Lab where we had to use a vacuum to get rid of air in water, The best way was to use a long clear tube made of lexan so as the vacuum pulled the air, the tube could be tapped with a rubber mallet. To get the water 99.9% clear of all air, this took upto 45 minutes with a 3.75 gallon sample, and never less then 40 minutes. So Steve is 100% (Well atleast 99%) correct in saying that these so called air seperators can not do a good job in removing air from the fuel. And if they could, why have the returned fuel drop back to the tank causeing more air problems? They have a good idea, but it can't work in the real world.

Any chance of taking a couple of pictures of this "bucket" and all the parts. It would be interesting to see the hardware to go along with your description. Good investigation so far!!

I got some pictures I took today of a extra sending unit I bought.

Couple things I have noticed is

1. The 1/2" hole on the bottom of the bucket with the check valve seems small to me, even for a stock HP truck. The hole is 1/2" but when the rubber check valve is in place ontop of the hole all the fuel has to come in around and from under the check valve that barely lifts off the hole. So it's no wonder that the FASS and Airdog will suck these buckets dry. And I don't think anything but a returnless pump will work with the stock pickup assembely.

2. You guys mentioned the "log" on the bottom, I think another function of the log is not only too return the fuel to the tank but if you look at where the log turns 90* UP it's open to the bottom of the bucket. So now as fuel is being pushed UP the return tube it's sucking more fuel from the bottom of the tank up with it into the bucket. Very ingenious if my assumptions are correct. Also since the return fuel is now actually being pushed UP the air in it will get pushed right to the top of the fuel level away from the pickup cup.

3. Anyone who fills there truck up before it gets very low to avoid getting any water or contaminites in the lines and filter is in for a rude awakening. The way the bucket is made, once you get below 1/2 tank the fuel is sucked RIGHT from the bottom of the tank all the time. The bucket sits RIGHT on the bottom of the tank and the check valve cant be more than 1/4" off the bottom. So for all those that have removed there tank for one reason or another I bet the tanks looked pretty clean inside, didnt they.

My .02 for now

Here's a few more pics

The check valve lifts off the bottom of the bucket very little, again I must say I'm amazed that enuf fuel gets in to supply a stock HP truck at full throttle with NO pump, I think the trick is the return line from the tank which sucks more fuel into the bucket when it comes back

The rubber piece on the ruler is the check valve

Someone finally believes me.

I wonder if we can just take the check valve out so as to supply more fuel to the bucket so the FASS/Airdog won't suck them dry.
If the valve gets exposed to air you would be in the same boat as leaving it in place anyway.

Or maybe make a bigger hole with a bigger check valve.
Nope that wouldnt work either as soon as the valve closed the pumps would suck the tiny 2 pint bucket dry.


I think the only answer to the FASS/Airdog is to make another pickup assembley, either a draw tube down to the tank bottom, which will leave you open to the possiblity of sucking air when on a incline or decline depending where you put the pickup.

Or try the Holley assembley with 3 diffrent pickups that Problem Child had a picture of and maybe that will work better.

Also the return line from the FASS/Airdog would be better if it was returned in a draw tube to the bottom of the tank away from the pick up unit.


How about having the FASS/Airdog return line tied into the Factory return line, that way the bucket would never go dry and the problem would be solved. But would that interfere with the factory return from the engine.

Just thinking outloud.

Couple things I have noticed is

1. The 1/2" hole on the bottom of the bucket with the check valve seems small to me, even for a stock HP truck. The hole is 1/2" but when the rubber check valve is in place ontop of the hole all the fuel has to come in around and from under the check valve that barely lifts off the hole. So it's no wonder that the FASS and Airdog will suck these buckets dry. And I don't think anything but a returnless pump will work with the stock pickup assembely.

Also the triangle divider bars take up surface area. I measured the 3 little traingle areas. They are 1/8" X 3/8" each. There are 3 of them. So whatever that equals up to? I equated it to a 3/8" diameter inlet.

2. You guys mentioned the "log" on the bottom, I think another function of the log is not only too return the fuel to the tank but if you look at where the log turns 90* UP it's open to the bottom of the bucket. So now as fuel is being pushed UP the return tube it's sucking more fuel from the bottom of the tank up with it into the bucket. Very ingenious if my assumptions are correct. Also since the return fuel is now actually being pushed UP the air in it will get pushed right to the top of the fuel level away from the pickup cup.

I used gravity to run some fuel through the return. Fuel will actually leak outside of the bucket back into the main body of fuel. Only air bubbles were coming up the stack. I used a small fish tank pum to add a little pressure. This then shot fuel up out of the stack falling back into the bucket.


3. Anyone who fills there truck up before it gets very low to avoid getting any water or contaminites in the lines and filter is in for a rude awakening. The way the bucket is made, once you get below 1/2 tank the fuel is sucked RIGHT from the bottom of the tank all the time. The bucket sits RIGHT on the bottom of the tank and the check valve cant be more than 1/4" off the bottom. So for all those that have removed there tank for one reason or another I bet the tanks looked pretty clean inside, didnt they.

I noticed my tank was very clean as well. Once I got inside the bucket I found debris, slime and other undesirables. The flex pickup tube had debris hanging in the ribs. The system is a bottom sweeping fool. No need for a bottom drain.

My .02 for now

Thats what I noticed.

I used gravity to run some fuel through the return. Fuel will actually leak outside of the bucket back into the main body of fuel. Only air bubbles were coming up the stack. I used a small fish tank pum to add a little pressure. This then shot fuel up out of the stack falling back into the bucket.



So the big question is how much pressure does the factory pump send the return fuel to the bucket with.
When you did the fish pump setup try putting the bottom of the bucket in some more water and see if it sucks that water out too.

I wonder if we can just take the check valve out so as to supply more fuel to the bucket so the FASS/Airdog won't suck them dry.
If the valve gets exposed to air you would be in the same boat as leaving it in place anyway.

If you take out the flapper you would be able to get more fuel in, but I think the pump would still when. I hope to verify this tommorow. If you sucked air, the pump could keep up depending on how long you sucked the air.

Or maybe make a bigger hole with a bigger check valve.
Nope that wouldnt work either as soon as the valve closed the pumps would suck the tiny 2 pint bucket dry.


I think the only answer to the FASS/Airdog is to make another pickup assembley, either a draw tube down to the tank bottom, which will leave you open to the possiblity of sucking air when on a incline or decline depending where you put the pickup.

Or try the Holley assembley with 3 diffrent pickups that Problem Child had a picture of and maybe that will work better.

If you put a tee in the pickup tube under the bulhead and ran it to the holley pickup you would have unlimited suply as long as teh second pickup was covered.

Also the return line from the FASS/Airdog would be better if it was returned in a draw tube to the bottom of the tank away from the pick up unit.

If the provided stovepipe was just a little different. The 1/2" spout needs to actually extend past the fillerneck down into the bottom of the tank. This would also keep it from interfering with the vent. You would have to do the install out of the truck.




How about having the FASS/Airdog return line tied into the Factory return line, that way the bucket would never go dry and the problem would be solved. But would that interfere with the factory return from the engine.

I havnt tries it but I think you would end up shooting fuel back up to the engine causing problems with the factory pump and wit the return abillatys.

Just thinking outloud.
I have the airdog 80. It is a slick little package. I would sure be able to make it work on my truck during all fuel levels. i would even be willing to block off the return and sacrifice the air separation funtion. I would still have a very reliable motor with a water separator and high quality fuel filter.

I am racking my brain as well. I am hoping a nights sleep will shed some light on it.

So the big question is how much pressure does the factory pump send the return fuel to the bucket with.
When you did the fish pump setup try putting the bottom of the bucket in some more water and see if it sucks that water out too.
I think it was Abear? who noted that the return line spits and sputters at idle. He never mentione what it did under load conditions.

The spitting and sputtering goes perfect with the log. It handled my artificial spitting and sputtering perfectly. The bubbles shot right out of the stack.

"If you put a tee in the pickup tube under the bulhead and ran it to the holley pickup you would have unlimited suply as long as teh second pickup was covered."

I think the holley unit has 3 diffrent pickup pods that are tied together in the tank, when 1 looses fuel a check valce closes so you dont get any air and it keeps sucking fuel from the other 2 or it goes down to one if 2 get uncovered. So you put 1 pod towards the front of the tank, one in the middle, and one in the rear of the tank.

I'll see if I can find the picture.



"If the provided stovepipe was just a little different. The 1/2" spout needs to actually extend past the fillerneck down into the bottom of the tank. This would also keep it from interfering with the vent. You would have to do the install out of the truck."

I have a transfer flow fast fill kit and I already removed that center flex tube to install the external vent kit, so I tied my FASS return line to the transfer flow return line.

The new Supertank I have has an external vent so the flex tube can be removed all together as well as the fast fill external vent I have now.

BTW Dieseldragon, thaks for the pictures. I was pissed I had all this apart with no camera. You saved the day.


Explain to me what is the Trippin billet pick up? I remember a picture of some fittings drilled through the plastic bulkhead. I thought it still used the factory bucket but alleveiated the bottleneck at the 90 degree? Whats that big aluminum cone?

"who noted that the return line spits and sputters at idle."

Thats it just spits and sputters?
I would of thought it would of been under more pressure at idle since the engine is not using much fuel and most is being returned, and less to almost none at full throttle.

2. You guys mentioned the "log" on the bottom, I think another function of the log is not only too return the fuel to the tank but if you look at where the log turns 90* UP it's open to the bottom of the bucket. So now as fuel is being pushed UP the return tube it's sucking more fuel from the bottom of the tank up with it into the bucket. Very ingenious if my assumptions are correct. Also since the return fuel is now actually being pushed UP the air in it will get pushed right to the top of the fuel level away from the pickup cup.
This sounds like a common motive-flow pump. If it is, it would have to be a venturi drawing "outside" fuel from the tank into the low pressure area of the venturi. Can you tell if there is a venturi shape inside the return tube that is open to the tank?

I think the CP3 is controlled by engine RPM? Maybe direct drive? Somebody knows.

This sounds like a common motive-flow pump. If it is, it would have to be a venturi drawing "outside" fuel from the tank into the low pressure area of the venturi. Can you tell if there is a venturi shape inside the return tube that is open to the tank?
The log has 3 stacks. The first is where the fuel goes down. The second is shorter with a little plastic cross in it.

The third is tall and appears to be same shape all the way though? It is kinda hard to se down in there, ecspecially since the log is under it but not conected. There is a 1/8" gap beteen the log and the third stack. That is how fuel spills into the tank and bubbles come upwards. I will look at it closer tommorow. I am all cleaned up today.

Explain to me what is the Trippin billet pick up? I remember a picture of some fittings drilled through the plastic bulkhead. I thought it still used the factory bucket but alleveiated the bottleneck at the 90 degree? Whats that big aluminum cone?
The billit pickup is the aluminuim "cone" piece seen in the picture's that replaces the factory plastic one that has the screen on it on the bottom of the pickup hose. The plastic screen is reused on the new pickup to keep the big crap out of the fuel lines.

The top of Trippin's pickup is machined larger to be able to replace the factory 1/2" plastic ribbed tubing with 5/8" fuel hose which then goes to a new -10 bulkhead fitting with larger fittings to accept the 5/8" hose. And then out of the sending unit with a larger -10 90* sweep elbow.


Edit: Going by memory here so correct me if I misworded anything Trippin or Diesel Tech, you guys know this product best.

"This sounds like a common motive-flow pump. If it is, it would have to be a venturi drawing "outside" fuel from the tank into the low pressure area of the venturi. Can you tell if there is a venturi shape inside the return tube that is open to the tank?"


I couldn't tell for sure with out a magnifying glass to see better I'll try looking again tomm, but I'm pretty sure it is venturi shaped and it is definitely open to the "outside" of the bottom of the bucket. And like I said earlier it looks like it's job is to draw fuel into the bucket to resupply it, and a very ingenuis system.

Those dam engineers are smart guys, we just need them to be working on our Horse Power side of the fence, and dseign a larger faster system ;)

OIC. I had most of it, I just did not realize that it replaced the lower portion of the factory pickup as well.

Diesel Dragon put the bucket up next to the lid and try to guesstimate where that third stack exits into the bucket. Kinda tight up there at the top.

"The log has 3 stacks. The first is where the fuel goes down. The second is shorter with a little plastic cross in it.

The third is tall and appears to be same shape all the way though? It is kinda hard to se down in there, ecspecially since the log is under it but not conected. There is a 1/8" gap beteen the log and the third stack. That is how fuel spills into the tank and bubbles come upwards. I will look at it closer tommorow. I am all cleaned up today."



I don't think the middle stack does anything, I think it's blocked off only the 2 outside stack work. Fuel returns down the one connected to the hose, gets to the bottom turns 90* goes across the "log" then turn's 90* UP and then stops and then it looks like there is a venturi on top of the "log" and then the stack continues UP into the bucket. Almost like a big " U " just with a venturi at the bottom of one of the legs of the " U "

I'll get some detailed pictures tomm after work.

As you suggested tommorow I will place the assembled bucket in some fuel and see if it can actaully draw fuel up from the outside. Today I did not notice because my pump and everything was all inside the same 5 gallon bucket.

Here's the link that PC had to the Holley pickup's.

http://www.jegs.com/cgi-bin/ncommerce3/ProductDisplay?prrfnbr=112587&prmenbr=361


http://dieselplace.com/forum/attachment.php?attachmentid=130&stc=1&thumb=1 (http://dieselplace.com/forum/attachment.php?attachmentid=130)





Just how do you mount them to the tank bottom?

Diesel Dragon - Thanks for posting the pictures. I makes this thread easier to follow as you guys discuss the fuel pickup design. It would have been fun to be at the design review of this device; to understand what the requirements were for the design and the implemented solutions.

Well it seems Bronco would now have to agree with what I've been trying to tell him. The FASS and Preporator or a external return type pump are no good for our application unless some other modifications are made. Since the manufacture has failed to disclose this, that's a problem. Any time the tank is under the height of the bucket you run the chance of it causing the truck to stall because it has sucked the bucket dry. The worst case is when you would be at low engine speed/load traveling down hill for long periods. Just think what would happen going down a mountain with a trailer on the back when the pump sucked the bucket dry............. engine stalls, no power steering, no power brakes............ not a good thing! These type pumps are not the answer and can cause more danger than there worth in my opinion in our application. Whether they do or do not remove air is open for debate.

Now you begin to see what we have been working on for the past year in looking at the fuel system. We will be introducing three different fuel pump systems. Each system has it own application. The first kit will be for stock Hp trucks up to 350 RwHp trucks. The second kit will be for stock trucks up to 420 RwHp trucks. The third kit is the big Hp trucks we are currently testing this system and feel it will not be ready until later this summer. The first two kits are in production now and we hope to be able to start shipping in 4 - 6 weeks. These are complete kits with no cutting of any fuel lines, they contain all necessary electronics and mounting hardware. You will need to drill a few holes during the install but thats it. All systems are of flow through design so you can switch the system off and it will run the same as stock. If for any reason you decided to go back to stock all that is left behind is the couple of mounting holes you drilled in the frame rail to mount the pump assemble.

The worst case is when you would be at low engine speed/load traveling down hill for long periods.
Just curious, why would this be the most likely time to suck the bucket dry?

Just curious, why would this be the most likely time to suck the bucket dry?
I think the theory is, with a low tank all the fuel is forward and there is no fuel available to replenish the bucket. Going down hill without brakes is worst case.

Yeah I understand down hill with no brakes or engine breaking would be a death trap.

I also understan how all the fuel will go to the front of the tank. I have actually had problems going down long grades here in Colorado. Other people have as well. Low fuel levels with a completly stock truck can be a problem here in Colorado. Inspecting the factory bucket shows why. Increased HP just makes the situation happen quicker.


I was curious why Diesel Tech said low load conditions? I am doing some bench testing with the airdog 80 and the factory pickup. I am trying to replicate factory return flows and really do not understand what they are. Are they high at idle or low? Are they high at upper RPM/HP or are they low? I need some factory return rates so I can better adjust my bench test. I wish I had pictures for you guys. I have lots a hoses,vice grips, regulators and other goodies. I am learning alot about our factory pickup and also this airdog 80. I just need some return flow charactereisitics.

I understand the rates will be dependent apon your lift pump and HP levels, I am just looking of characterisitcs.

Low Load/ Engine Speed is when the pump is returning max. fuel via the filler vent hose and down hill keeps the fuel away from the the bottom of the bucket. Also the factory return is at it lowest volume of return. You have to understand the FASS/Preporator pumps the same amount of fuel at all times, it either goes back to the tank as return fuel via the filler vent or to the engine to be burned but it always moves the same volume. This is only one of it's problems. Traveling at any speed without brakes is dangerous.

Bronco

You will need to do what we have done and start by doing the measuring of the fuel requirements and develop the data necessary to understand all of what is going on. You may not like it but we've spent a lot of time and money to develop this information and I just cannot give it away. We are in business to make money just as everyone else is and giving away all the test data just makes no sense. I tried to get you going the right way and I think your finally get started on doing real testing. Enjoy the testing and finding the answers as we have.

You have to understand the FASS/Preporator pumps the same amount of fuel at all times,

Dieseltech I cannot speak for the FASS . However I can speak for the Preporator. When the Preporator has the feed to the engine completly closed all the fuel is going to the filler neck except for the small amount that is being retuned to the bucket and the small amount used to idle the truck. We agree.

However the flow rate to the filler neck is substantially lower than the normal output to the engine. WHY? Because at a certain pressure it has an internal bypass. So basicaly it returns fuel within its self if the pressure gets to high. So when at idle there is not as much fuel going to the filler neck as one might think at first glance.


You may not like it but we've spent a lot of time and money to develop this information and I just cannot give it away. We are in business to make money just as everyone else is and giving away all the test data just makes no sense. I tried to get you going the right way and I think your finally get started on doing real testing. Enjoy the testing and finding the answers as we have.
Dieseltech your support is appreciated and I do listen to everything you have written. I will continue to test and I will enjoy. My initial testing tells me that we will have similar outcomes but not for the same reasons you have identified.


I will post more as I learn more. Next step is to run the truck with the airdog 80 in a 5 gallon pail. I want to verify what is happeing with a idling truck and the airdog supplying the fuel.

Heres some more pics of the "log" under the bucket pickup.

Looks like it a venturi effect to me to resupply the bucket with more fuel.

More good pics.

I tried to test if the log caused additional fuel to be fed into the bucket. I was not going about it correctly so my results were inconclusive. Maybe I will try more tommorow.

It would make sense though, because not very much fuel at all comes in the bottom flapper. However I did notice if you raise the bucket up and down ever so slightly it causes the flapper to force feed fuel into the bucket. I wonder if the spring loaded bucket , pressing against the bottom of the tank ocsilates just enough to pump fuel into the bottom flapper?

The bucket has to get fuel somehow or it would be running out of fuel anytime the tank level was below the lip.

I will post more as I learn more. Next step is to run the truck with the airdog 80 in a 5 gallon pail. I want to verify what is happeing with a idling truck and the airdog supplying the fuel.
So I hooked the air dog 80 to my truck today. I used the factory pickup but it was in a 5 gallon bucket. i had clear fuel lines going to the factory steel feed and return line. I was able to visually see what was happening at idle all the way to 3000 RPM. No load of course. A dyno would have really shed the light on things, oh well.

So here is what I noticed. At idle the Dmax uses very little fuel. It also return very little fuel. I mean maybe 1 gallon per hour feed and 1/4 gallon return. That is just a guess. I am sure if Steve reads this he will correct me.

So this causes the Preporator airdog to basically send all of its output to the return filler neck. Unfortunatly the feed to the engine is next to nothing and this causes the air separation funtion to quit working as well. So at idle the air dog 80 does nothing but cause the fuel to become thick with tiny bubbles.

If the fuel level falls below the top lip of the bucket, the airdog 80 will suck the bucket dry in approx. 3 seconds. So really there is no way to run the airdog 80 on my 03 dmax at idle, with the fuel level below the lip of the factory bucket.

You would have to modify the factory pickup apparatus. you would then be left with the fact that the airdog 80 had plenty of fuel, but it would still be returning it all and very little would be going out the feed side. So to make the air separation funtion work at idle you would also have to let some pressure off of the feed side. This would require a tee on the engine feed line. You would have to then return some of this unused fuel back into the fuel tank. So 2 modifications would be needed to make hte airdog 80 work correctly at idle.

In the higher load conditions the airdog should work as advertized. As a matter of fact, I would think the pump would pump so much fuel to the engine that it would drain the factory bucket if the fuel level was below the lip. So anyway you shake it, the bucket really needs improvement or you need to keep your tank above 1/2 tank. I would think this is true for any high HP big lift pump application. The factory bucket can only let so much fuel into it.

If the bucket runs dry and the pickup becomes uncovered, you would not realize it untill all of the fuel was sucked out of your factory fuel filter and fuel lines of the air pocket hit the engine. So that might give some of you something to think about.

I have come to the conclusion that there are 3 fuel conditions inside our factory fuel tank.

1. Fuel level is above the bucket lip and supply is unlimited.

2. Fuel level is below lip of bucket and supply is limited to 16 oz plus the little that can flow in and what you have in your fuel filters and lines.

3. Fuel level is so low that the bucket momentarily becomes completly isolated from any fuel in the tank. At this time you would have only the 16 oz of fuel plus everything that was in you filters and lines.

I you think about these 3 scenarios and compare them to past post about stalls, codes, steep grades, mysterious air in the system and what not I think you might have a change of opinion. I know I have.

One final thought I have in regards to aftermarket lift pumps.

At idle the engine is demanding very little fuel. There is also very little fuel return even with the pressure of the lift pump pushing against the CP3. It was stopping 15 PSI today.

So any pump you choose to use, either better have i'ts own regulated return or an internal bypass. Otherwise you are just pushing fuel up aginst a brickwall at idle. If you do not have some type of bypass or fuel control, the more time you spend idling the more time your pump will just be spinning it's wheels and tearing it's self up.

So here is what I noticed. At idle the Dmax uses very little fuel.
So this causes the Preporator airdog to basically send all of its output to the return filler neck. Unfortunatly the feed to the engine is next to nothing and this causes the air separation funtion to quit working as well. So at idle the air dog 80 does nothing but cause the fuel to become thick with tiny bubbles.

If the fuel level falls below the top lip of the bucket, the airdog 80 will suck the bucket dry in approx. 3 seconds. So really there is no way to run the airdog 80 on my 03 dmax at idle, with the fuel level below the lip of the factory bucket.

So 2 modifications would be needed to make hte airdog 80 work correctly at idle.

In the higher load conditions the airdog should work as advertized.
I you think about these 3 scenarios and compare them to past post about stalls, codes, steep grades, mysterious air in the system and what not I think you might have a change of opinion. I know I have.So now that you have done the testing you've had a change of heart. I think you owe a few people an apologie for some of your comments made before in this and other fuel pump threads.

Yeah I am sorry for spreadng mistruths. I wanted to beleive the info provided by the owner. I became focused on the fact that the Preporator is constructed bettter and had more thourough internal passagges and is an overall better design. If correctly sized and applied correctly the Preporator is a better unit and will perfrom as advertised. To work correctly on our trucks, it needs a modified pickup and a regulated return line.

So now you apoligize for being a condesending, pompus, egotistical a-hole who takes credit for every little piece of information that is presented on this website. You read what one truck owner post, go to work and tinker with it then you claim you discovered America. :exactly: HACKER! :blahblah:



:lol: :lol: :lol:

I here the lapdog posse yipping now.

Yeah I am sorry for spreadng mistruths. I wanted to beleive the info provided by the owner. I became focused on the fact that the Preporator is constructed bettter and had more thourough internal passagges and is an overall better design. If correctly sized and applied correctly the Preporator is a better unit and will perfrom as advertised. To work correctly on our trucks, it needs a modified pickup and a regulated return line.

So now you apoligize for being a condesending, pompus, egotistical a-hole who takes credit for every little piece of information that is presented on this website. You read what one truck owner post, go to work and tinker with it then you claim you discovered America. :exactly: HACKER! :blahblah:



:lol: :lol: :lol:

I here the lapdog posse yipping now.If that's what you call someone who sits down and does the work, spends a year making changes and figures out the probelms then I resemble that remark. On the other hand has the owner of Preporator feed you today!
I think this comment says it all
"If correctly sized and applied correctly"
I always thought this was the job of the designer which in this case would have been Charlie from Preporator:( and he just happens to be the one leading you around like a lost puppy dog.:lol:

yip yip):h

Bronco,
I appreciate your doing this. I've also purchased an Airdog and have yet to install it. On the LLY's the vent goes back into the fuel sender. I'm wondering if this would make a difference? I also have a Transferflow 45 gal. tank, and it has a tee on it. You split the vent line that comes from the filler neck and put it on one side of the tee and the other side goes to the sending unit. The next tank I sell for a LLY I will study this a little more. I don't feel like pulling my tank just to check it out. I cannot understand why it wouldn't work on a LLY. Again thanks for you input on the Airdoq. tpitt

First let me make a sincere apoligie to MikeL. I insinuated that he might have installed the airdog incorrectly. That is not the case. I am sure he installed it per the manufactures reccomendations and it still did not work with any fuel level below the top of the factory pickup. On my extended cab that happens to be 8 gallons of fuel.

I would also like to congratulate MikeL for coming forward and presenting the facts. To my knowledge he is the only one who publicly acknowleded the " airseparators" had problems. Why the others never mentioned it on this forum is beyond me. To not know there is a problem is one thing but to know of a problem and not share it is another. So I am sorry MikeL and good job for presenting the facts as you found them.


Okay so now on to the correct operation of the airseparators.

To funtion as advertised the "airseparators" need an unlimited supply of fuel at all times. In the current LB7 configuration the factory bucket can become drained. When this happens the air separators do not have adequate fuel supply. While they are struggling for fuel to pickup they can actually make quite a foamy mess of the current fuel supply. If left unchecked the fuel can foam out of control into a perpetual motion. So first off they need an unlimited fuel supply.


Second to separate air correctly they need to have a flow split. What this means is that some of the fuel needs to be going to the provided return and the rest of the fuel needs to go to the provided engine supply line. This has to happen in a predetermined ratio. So in the case of the factory DMAX it uses very little fuel at idle and low load conditions. The factory return line also returns very little fuel during these conditions.So basically all of the fuel is being picked up by the "airseparator" and sent directly back to the fuel tank. There is no air separation or much of anything usefull happening at this point. It is deseptive to think the factory return line is allowing any fuel pump to pump fuel to torwards the engine during idle and low load conditions.

So with the 2 above points in mind, a need for a constant fuel source and a need for a constant fuel bleed off via the engine supply line is what would be needed to make these "airseparators" work as advertized during any and all circumstances.

You need to modify your factory pickup. You can do this by drilling out the flapper on the bottom or by installing the HOLLEY pickup. Holley uses 3 individual pickups placed at the front, middle and rear of the factory tank. These mods have not been tested by me so perform them at your own risk. I am sure there are other methods of insuring constant fuel pickup as well.

The second modification needed would be to install a return style fuel pressure regulator on the output/engine supply line of the "airseparator" This would allow constant fuel flow from the pump. This would allow your fuel to be constanly filtered for water, dirt and also air removal.

So in my opinion 2 separate modifications are needed to to make the "airseparator" funtion correctly. In trade off, you would not install the provided return filler neck. So you would subtract a step from the original manufatures instructions. NO NEED TO CUT THE RETURN FILLERNECK. Besides it was specifially designed to allow the filling of your fuel tank to be hassle free and minimize the amount of fuel spilled down the side of your truck. Not a vent as mentioned before but a method of keeping fuel off of the side of your truck. EPA likes that as well.

Basically the factory bulkhead could be drilled out and a return line could be placed in the center position. Just like the Trippin fitting but for a return instead of a pickup. You would return the regulated feed supply to this point and also tie in the "airseparators" return at this point. Tie the airseparator return after the regulator so as to not send pressure into the outlet of the airsepartor.

So if a guy drilled the factory bulkhead and returned fuel at this point the sytem would be no worse off then the original factory designed system. You would still need to possibly tie in the HOLLEY pickup system, modify your basket of keep your tank 1/2 full. However by returning fuel via the bulkhead you are also attempting to keep the basket full.

I just want you all to know, I never installed any of these products untill now. I never commented on the operation in the vehicle because there were members here who said there were no problems. They even ridiculed me for suggesting the installation was difficult and flawed. The only previous research I did was to identify if these products reallly separated air and if there was a better product out of the 2 available.

If I would have proceeded with the install, I would have found these problems 1 year ago. This current thread has went in one direction regardless of the input from the resident experts. I was in search of the truth and I found it. Along with alot of other usefull information in regards to the factory fuel system. Thanks for the support from Diesel Dragon. The pictures were excellent. I would also like to thank those of you that are more interested in learning rather than always being right.


In the future I hope to implement my solutions and prove there usefullness. I have contacted the manufacture and explained the problems and the solutions. It is in his hands now. The airdog 80 is very well designed and very rugged. It is a compact package with excelent filtratration. It does do everything it claims to, just not when installed per the manufactures instructions.

First let me make a sincere apoligie to MikeL. I insinuated that he might have installed the airdog incorrectly. That is not the case. I am sure he installed it per the manufactures reccomendations and it still did not work with any fuel level below the top of the factory pickup. On my extended cab that happens to be 8 gallons of fuel.

I would also like to congratulate MikeL for coming forward and presenting the facts. To my knowledge he is the only one who publicly acknowleded the " airseparators" had problems. Why the others never mentioned it on this forum is beyond me. To not know there is a problem is one thing but to know of a problem and not share it is another. So I am sorry MikeL and good job for presenting the facts as you found them.http://www.dieselplace.com/forum/images/smilies/exactly.gif http://www.dieselplace.com/forum/images/smilies/exactly.gif http://www.dieselplace.com/forum/images/smilies/exactly.gif

.....and they all lived happily ever after.

THE END

http://www.dieselplace.com/forum/images/smilies/biggrin.gif

Bronco
Very good post and very informative.
mike

Mike L
Do you know if it will work on the LLY which has the vent going into the fuel sender? I really haven't had time to play with mine. I figure when I install another LLY tank, I will take a closer look at the pickup. The theory is good if theres some way we can make it work. Glad everyones getting along now as this is an interesting subject and I'd hate to have such an expensive item sitting on my shelf collecting dust. Thanks, tpitt

The tripple pickup assemblly by Holley is no longer available, there vendor that manufactured it for them is no longer making them and Holley has no plans to replace it. So that idea is out.


I plan on modifying my spare sending unit with the Trippin pick up and then like Bronco suggested by running the return line from the FASS in through the center port (but drilled out and replaced with a larger fitting) and run a fuel line inside to just above the the fuel bucket.
It may work well by resupplying the bucket with the fuel that the FASS removed, like the factory system does, or it may just return a lot of fuel that is entrained with air and when the fuel level is low it may splash around and make more air bubbles which could cause more problem's.

One way or the other I'll find out.


I also plan on modifying my Supertank by installing 2 more bulkhead fittings, 1 will be another return from the FASS that I plan to run to near the bottom of the inside of the tank. Hopefully with the returned fuel being reintroduced into the existing fuel it will prevent any agitation and keep the air bubbles to a min.
And then another fuel pickup tube near the bottom of the tank near the sending unit to see if it will allow me to be able to use more of the tanks capicity than the factory sending unit does.

I'll try all the combinations and see which one if any works best, and plug the extra lines I won't be using.


Hopefully I can get this accomplished in the next month or so as it's getting to be a busy time of year at work.


DD

Mike L
Do you know if it will work on the LLY which has the vent going into the fuel sender? I really haven't had time to play with mine. I figure when I install another LLY tank, I will take a closer look at the pickup. The theory is good if theres some way we can make it work. Glad everyones getting along now as this is an interesting subject and I'd hate to have such an expensive item sitting on my shelf collecting dust. Thanks, tpittI am under the impression that the LLY fuel pickup bucket is identical to the LB7? If this is the case, you will have to modify it. Anytime the fuel level gets below the top lip of the bucket the airdog will suck the bucket dry. If you suck the bucket dry things get out of control in a hurry. So the first thing is to make sure your fuel pickup will always be covered with fuel.

Then you have to determine how to return the fuel. It is my understanding the LLY filler neck does not have the internal sleeve? This would allow you to use the supplied filler neck retrun apparatus. Becareful not to introduce dirt into your fuel tank when you hack into your filler neck. Best if done with tank removed.

The third problem is this. When at idle or low load conditions, the "airseparator" is pumping lots of fuel with only one place to send all of this fuel. This place is the return filler neck apparatus the kit came with. At first glance this looks like an acceptable mode of operation but it is not.This fuel has not went through the unit. It is not free of air and it is not filtered as far as I know. So you are basically recirculating lots of fuel with no real benifit. It is also adding extra ariation to your fuel tank. So to combat this third problem you need to install a regulated return on the output side of the "airseparator".



1. So you need to modify your pickup to insure it will always be covered with fuel.

2. You need to install the fillerneck return apparatus if no internal sleeve is present.

3. You need to install a regulated return line on the output side of the "airseparator" to gain full benifit.

If you only conduct steps 1 and 2 you will be operational but not filtering and separating air at full capacity.

I think combining steps 2 and 3 are the best option.


Until somebody puts a solution in kit form, you will probally just have to go disect your truck yourself,or you can keep your fuel level above 8 gallons. More when traveling up hill because the pickup is front of center.

These pumps can be made to operate as advertized with some modifications.

Another option would be too delete the air separation feature. Basically plug off the return line. You would then need to control output pressure. This could be done with a regulated return line or a voltage controller box. The voltage box is 245.00 dollars. If you were to install a voltage box referenced off of pressure you would not have to modify your factory pickup. You would not be draining the bucket any quicker then the factory setup. It would allow you to have the correct fuel pressure over a broad range and your fuel would be free of water and dirt. No air separation, yet clean pressurized fuel.

Bronco,

I have an extended cab / short bed truck with the 26 gallon fuel tank (like you). When do you estimate that the "fuel cup" within stock fuel system becomes not covered by fuel in the tank ? (Assume a level truck for the time being,,,, how many gallons from full until the top is uncovered).

Thanks,
Alan

Couple things I have noticed is

1. The 1/2" hole on the bottom of the bucket with the check valve seems small to me, even for a stock HP truck. The hole is 1/2" but when the rubber check valve is in place ontop of the hole all the fuel has to come in around and from under the check valve that barely lifts off the hole. So it's no wonder that the FASS and Airdog will suck these buckets dry. And I don't think anything but a returnless pump will work with the stock pickup assembely.

2. You guys mentioned the "log" on the bottom, I think another function of the log is not only too return the fuel to the tank but if you look at where the log turns 90* UP it's open to the bottom of the bucket. So now as fuel is being pushed UP the return tube it's sucking more fuel from the bottom of the tank up with it into the bucket. Very ingenious if my assumptions are correct. Also since the return fuel is now actually being pushed UP the air in it will get pushed right to the top of the fuel level away from the pickup cup.

3. Anyone who fills there truck up before it gets very low to avoid getting any water or contaminites in the lines and filter is in for a rude awakening. The way the bucket is made, once you get below 1/2 tank the fuel is sucked RIGHT from the bottom of the tank all the time. The bucket sits RIGHT on the bottom of the tank and the check valve cant be more than 1/4" off the bottom. So for all those that have removed there tank for one reason or another I bet the tanks looked pretty clean inside, didnt they.

My .02 for now
Diesel Dragon,
Every bit of this post is dead on accurate. Period...... :beerchug:
I've also previously removed my sender and this was exactly my conclusion as well. It's a greatly engineered design but definitely NOT user friendly for high fuel recirculation rates in it's stock form, thus my decision to run a pump that recirculates no fuel while keeping the stock sender features which I like. IMO an overbearing pump with large recirculation rates is no where near the best solution out there right now. I'd much rather send the fuel only where it can become a benefit and not a problem. Right now I'm thinking that re designing the sender to handle high return rates while maintaining all beneficial stock features will be a major task and will have to come with a healthy price tag to match. I do however wish the best of luck to those that are involved.
Just My .02

Bronco,

I have an extended cab / short bed truck with the 26 gallon fuel tank (like you). When do you estimate that the "fuel cup" within stock fuel system becomes not covered by fuel in the tank ? (Assume a level truck for the time being,,,, how many gallons from full until the top is uncovered).

Thanks,
Alan
I never started with a COMPLETLY empty tank and fill it until the bucket was covered but I did take a few measurments and make some guesstimations.

The tank is 14"tall. The bucket is 4&3/4" tall. From the fuel that I removed and the fuel I added I calculated 8 gallons when on a level surface. This would give you about 1/2" above the bucket.

So 8 gallons to stay covered. That does not always equate to 1/2 tank on your fuel gauge. Just depends on how your sending unit and fuel gauge is calibrated but approx. 8 gallons covers the bucket.

I know what you mean about the gauge accuracy. Anyway, if I fill-up and and take 16 gallons or less (allowing some margin), then the cup should always be full (on a level surface).

Bronco,
The fuel cup is similar to the LB7, but the fuel neck is different (It has a separate vent hose) with the vent going into the center port of the fuel pickup. There are 3 ports on the LLY's. ( I'm assuming it is the center port as offhand I don't remember for sure.) On my 45 gal Transferflow tank you actually cut the vent hose from the filler neck and attach it to one side of a tee on the tank. The piece you cut off goes from the other side of the tee into the factory fuel sending unit. This is why I am wondering if the Airdog would work. Part of the fuel would be returned to the tank through the tee and part would be returned through the sending unit where the origional vent hose goes. tpitt

This subject is now going where it should. I am learning a lot and getting some ideas from you guys and am about to make some mods on my spare unit. I will post my mods with pictures and see if any of you guys shoot it down.( i welcome that ) As far as how much fuel in the tank before performance suffers; I say 1/3 tank and you are walking a fine line. Let me clarify this 1/3 tank. In a stock fuel system, anything below 1/3 tank is marginal as far as keeping the bucket submerged for optimum fuel delivery. You will not have problems with a stock truck all the way down to empty. You will lose some performance, although not noticable for most of us. The racer will know it and see it in his track times. Add a Trippin p/u in a stock system and you will have no problems. Add a return fuel sysrem with the Trippin p/u and you have problems. Bronco has explained this very well.

mike

Could a pump be designed that dosent need to be returned?
What about having the pump turn on at a desired boost level or rpm?

The truth is you will have problems with a return type pump with or without the Trippin fuel pickup. That has been said for a long time, The pickup is not the problem, the problem is with the FASS or Preporator pumps. The factory air separator works just fine on the return fuel coming from the motor. You have two choices here:

1. Do not use a return type pump, problem solved or
2. Use a return type pump and figure out how to make it work as they do not work as supplied below ~ 1/2 tank.

The pickup was designed to solve a restriction in the fuel system and it does that perfectly. I think anyone who is adding power should have one installed along with a proper lift pump system and you will have a good fuel system. I believe the supplier of the return type pump should be the one resolving there poorly designed kit or offer refunds to those who have them.

Could a pump be designed that dosent need to be returned?
What about having the pump turn on at a desired boost level or rpm?
They have been already. We will have two systems ready shortly that will work and have full safety features built in. ;)

And here i thought i was on to sumthin new...........................LOL):h
I take it you have ideas on both setups?
Could u pm me with some pricing.................If u have an idea yet on what they will be worth..............:)


They have been already. We will have two systems ready shortly that will work and have full safety features built in. ;)

A lot of technical dialog here, most of which I hope will result in better products in the future. As a user of the FASS system for a year now, I will atest that it does a pretty good job of improving fuel flow to the engine. No diagnostics, just my impression from running the Extreme tune with it.

I have run out of diesel to the point of killing the motor at least 6 times in the last year, mostly right after getting the FASS installed and not knowing what was happening. Before running the FASS I ran my truck out of diesel once and put 26.1 gals of diesel in the 26 gal tank. All six times I ran out of diesel with the FASS on, I could not get more than 20.2 gals in the tank. In other words, the truck would die with nearly 6 gallons of diesel still in the tank. One time I was coming down a freeway offramp (going to the station) when the engine died I had to make a very nervous hard right at 35 mph with no brakes or power steering (N/B I-15, El Norte Parkway, Escondido, CA). I had a needle over 1/4 tank indicated when that happened.

I certainly hope the maker of the FASS comes up with a fix or workaround, as I really like thier product but not the 19 gal effective capacity of my tank. I plan to wire an on/off switch in the meantime to turn the pump off if needed.

Doug

I will be installing the TTS fuel system in my truck shortly in my quest to flog some Dodge a$$. ( are you listening Tim?) ):h :D

I plan to wire an on/off switch in the meantime to turn the pump off if needed.

Doug
Happened to me the other day. The tank was getting low on the drive to work and I forgot to turn the Fass off. I came out to a no start at the end of the day. It had obviously filled the system with air on the drive in.

Solution: I turned the Fass on until my fuel pressure gauge showed 8 psi, then quickly turned off the Fass, and started the truck without problem. Then drove to the fuel station and fill her up. :D

Bronco,
The fuel cup is similar to the LB7, but the fuel neck is different (It has a separate vent hose) with the vent going into the center port of the fuel pickup. There are 3 ports on the LLY's. ( I'm assuming it is the center port as offhand I don't remember for sure.) On my 45 gal Transferflow tank you actually cut the vent hose from the filler neck and attach it to one side of a tee on the tank. The piece you cut off goes from the other side of the tee into the factory fuel sending unit. This is why I am wondering if the Airdog would work. Part of the fuel would be returned to the tank through the tee and part would be returned through the sending unit where the origional vent hose goes. tpitt
I have never looked at an LLY truck. There could also be other small differences between the different years and specific emmision packages.

Regardless of your particular build you have to insure the pickup stays covered with fuel at all times. If you have a transfer flow tank that could work to your advantage as well.

Aeromotive, been there done that!

http://216.242.145.16/products/content_p.phtml?pk=13

I wired my FASS to a seperate relay with a switch in the cab so I manually turn it on and I can shut it off when the fuel gets low to avoid any problem's till I fill up again.

Since the FASS is a flow thru design and will allow the engine to still run with the pump off, has any one hooked up a test vacum guage to see how much "restriction" the FASS pump and filter assemblly adds to the stock fuel system when the pump is not running?

DD,

I drove my truck with the Fass turned off for approx. 1 month just to be sure of it's flow through design. In this fashion I experienced many different scenarios with regard to fuel level, temp, road conditions, etc.

I never thought about checking restriction though. :(

Diesel Dragon,

Good idea...I will take a reading tonite or tomorrow to see the difference...I am assuming the drop through my filters will be the same whether they are under pressure or Vacuum? Right now my drop is 1psi under pressure. 10psi at the output of the Airdog and 9psi at the test point.

Ya I was just wondering if it put a "big" restriction on the factory lift pump and might cause problem's to the factory lift pump (read expensive to fix I'm sure) in the long run if we ran the FASS pump in the off position a lot. Or if it didn't put much more of a restriction on it and it shouldnt be a concern.

Probablly a lot more restriction in cold temps too compared to warmer temps.


What's the factory vacum reading at the test port with a new factory filter and stock fuel system anyway?

Any one have a Nicktane filter installed to check what the vacum guage reads with that filter added to the stock system?

Any one got a vacum guage to check the reading with a FASS equiped truck with the pump turned off?

Anyone have a Nicktane filter AND a Fass equiped truck with the pump turned off to check the vacum reading?

Maybe I should just buy a vacum guage, huh? lol

DD

RonJT,

Are the Air Dog pumps a flow thru design also?

DD,

Yup. I have filter heaven..both nictane kit and the Racor kit. Three filters...CAT 1r0749, R90S and old style OEM=1psi drop.

I have the filter guage from John Kennedy...hopefully I will get to it tonite or tomorrow.

The stock fuel system requires approximately 2.25-2.50 inHg of vacuum to move the fuel from the fuel tank to the injector pump.

RonJT - are you still working several blocks away from me in El Segundo? If so, we need to get together some lunch hour and compare your Kennedy gauge with my Kent-Moore gauge. I am interested in how the readings compare on a stock fuel system.

Alan,

Yes..I am at the corner of Continental and Mariposa. Probably easier to come by my parking lot...no ID checks.

Let me know...Tomorrow would probably be best.

RonJT,

Are the Air Dog pumps a flow thru design also?
When DIESEL 5's airdog quit I had to flatbed him to my shop and bypass the pump to get him to work. I guess the answer to your question is no.
mike

Hey Mike it is a flow through design with very little resistance. I think what happened in your situation was the dreaded foam bomb these pumps can create when trying to operate without adequate fuel supply. From my testing they can suck just enough fuel and return just enough fuel to litterly create a giant foam bath. So my guess is that you probally sucked foamy fuel all the way up to the OEM filter and completly filled the factory system with foam. This caused the factory system to loose prime.

If you would have shut the pump off, and then released the air bleeder screw up at the OEM filter and then pumped for proabally 10 minutes straight, you might have got it to go again.

Just a guess to what happened, but the airdog 80 I have is flow through.

Yeah---the truck will run without the pump on yet connected. When I first put the the thing on...the power connection kept comming undone...and I had to drive it...so I just did without power to the pump.

Just another illustration here.

1. Fuel tank level falls below top lip of factory bucket
2. Airdog 80 removes all fuel from bucket in about 3 seconds.
3. Factory pickup and CP3 pump continues to pull a vacum
4. CP3 pump sucks fuel from filter and fuel line
5. Pickup has had little to no fuel covering it this entire time
6. Air hits factory CP3 pump.
7. Loss of prime and loss of fuel.
8. Truck dies and will not restart.

Quickest way to gain prime after no start condition would be to fill tank with 8 gallons or more and turn electric fuel pump back on.


It is best to shut off "air separator" when below 8 gallons of fuel.

The factory system is designed to suck up small pockets of air. It can do this anytime your fuel level is below the top lip of the bucket. Usually the air pocket is small enough to be passed right back to the fuel tank via the factory return line. If the air pocket is too large even a bone stock fuel system will loose prime and go into a no start condition.

Wide open extended blast can suck air.
Extended up hill travel can suck air.
Anytime the fuel level is below the factory bucket lip, you run the risk.

Sorry if I am being redundant. Up untill last week, I had always envisioned an
uninterupted circle of fuel travel.

Well here are the numbers.

9psi with pump on at test point.

3inches of Vacuum with the power disconnected to Airdog at test point.

I have three filters after pump....Baldwin BF7587(equivalent to the 1R0749) plus R90S plus the original style OEM.

I think the R90S is accounting for about 0.45inches of Vacuum if I remember the filter spec correctly.

Sometimes I don't know where I left my brain. :eek: My SPA fuel pressure gauge is connected to the hose where the factory test valve used to be.

Gauge reads -1.0 to -1.5 under normal driving conditions. WOT runs will display a reading of -4.0 to -4.5. This includes the optional 10 micron Fass filter (not the 30 micron that was supplied) and the factory fuel filter.

So in a round about way, I did remember to check the numerical value of the restriction of the Fass turned off.
I just forgot that I remembered???? :confused: :eek: :D

So, with numbers of 1 to 3 to a max of 4.5 inches of vacum the factory pump shouldn't have any problem's pulling that for an extended time?

And I'm guessing that's with clean filters.

Do you know what a factory system with a dirty filter with about 15,000 miles on it will pull for a vacum? Are we still well below that?

Diesel Dragon shutting the pump is a good quick fix. No disagrement there.

I am interested in coming up with a permanent fix that allows us to use the pump 100% duty cycle. I mentioned our situation to the tech at Aeromotive and he suggested running the fuel back to the bucket before I had even told him that's what we thought. So I think we are good there.

I still think we need a regulator near the engine with a small return line. This would allow the "airseparator" to flow clean fuel out the supply side at all times rather than returning most of the fuel back to the tank via the short loop.

So what I am getting at is this. Do you have any good sources for fuel fittings, tubing, regulator and the other dohickys we might need? I would like to put a kit together and then tear my truck back apart for the install.

Hey Mike it is a flow through design with very little resistance. I think what happened in your situation was the dreaded foam bomb these pumps can create when trying to operate without adequate fuel supply. From my testing they can suck just enough fuel and return just enough fuel to litterly create a giant foam bath. So my guess is that you probally sucked foamy fuel all the way up to the OEM filter and completly filled the factory system with foam. This caused the factory system to loose prime.

If you would have shut the pump off, and then released the air bleeder screw up at the OEM filter and then pumped for proabally 10 minutes straight, you might have got it to go again.

Just a guess to what happened, but the airdog 80 I have is flow through.
Bronco
DIESEL 5 got the salespitch of his life from Larry at Prep. and spent big bucks for the airdog that had never been installed on a Duramax ( he was lead to believe differently). I was asked to take pictures and report to them how I did the install. I was sent every bracket and hose and clamp. DIESEL 5 was the first airdog on a Duramax and I was the first installer. His airdog failed electronicaly and did not flow through. After spending big bucks on this pump you are suppose to diagnose it? You break down on the freeway and pay a monster tow bill and just what is airdog going to do for you? They lied to DIESEL 5.

Hey Mike,

What is going on here sucks. No doubt about it. Why do you think I started this thread with a very scientific basis? I provided unbiased info for all to see. So now how these companys handle it, with there customers is out of my control. Alls I can do is try and make a cost effective solution for those that already spent the money and want to use a pump they have an investment in.


I understand your pump did not work and left you stranded. I did my best to explain my theory on how and why that happened. Never the less you are still screwed with a big bill and still no working system. That sucks!

I am not condoning any activities here. The Diesel Place is full of products that are unnessacary or do not do as claimed. It is also has some products that cause vehicle reliability issuses and safety issuses. If the products do not cause safety issues for you and your truck, the huge smoke cloud, overstressed breaking system and steering system is causing safety issues for unsespectic bystandards and the enviroment. There are good products here as well. Sometimes it is just fun to separate them out.

I am not here to judge, I am just here to pinpoint what the problem is and what it would take to fix it. I think if a potential customer were to read this entire thread ( minus the ego) he could come to his own reasonable conclusion.

So we have done good here. If a perspective buyer reads it, if one of the "airsepartators manufactures" reads it and if a current pump owner reads it. We all have shared and now have a better understanding. :ro)

I still think we need a regulator near the engine with a small return line. This would allow the "airseparator" to flow clean fuel out the supply side at all times rather than returning most of the fuel back to the tank via the short loop.

So what I am getting at is this. Do you have any good sources for fuel fittings, tubing, regulator and the other dohickys we might need? I would like to put a kit together and then tear my truck back apart for the install.

I don't have a good supply, just the local hydraulic parts store.

I happened to be talking to the Aeromotive tech yesterday too lol
I was asking about their #18650 Custom sump, but he said it was a metal one that needed to be welded into a metal gas tank, so that's out. :(

He mentioned the pump that they have for marine application's will work for diesel's too, but it's expensive too # 11108 $419 at summit. Graph shows it flows about 115 gph at 13.5 volts at 10 psi.

He also mentioned having a custom tank with baffles and a bigger sump for the pumps made by www.rickshotrodshop.com (http://www.rickshotrodshop.com) but I'm sure that would be too expensive.
But I think if anyone was going to do any off road or long distance racing they would have to do something with the tank because in my opinion the stock bucket would not be adequete to supply a lot of fuel for a high Horsepower application on offroad courses with a lot of bumps and inclines and declines once the fuel level dropped below half a tank.

Aeromotive also has a regulator for low pressure system's that you might want to take a look at for your return idea # 13207 $200 :(

Where would you return the fuel to, with your new regulator ?

How about "T" into the factory return line, I wonder if it can handle the extra fuel ? The steel lines might, but once it get's into the bucket it chokes down at the "log".

I like the idea of putting a new return line in place of the 3rd fitting on the bulkhead that's not used, it would return the fuel right back to the bucket so it would never run out, BUT

1. Would the fuel get overheated by constantlly recirculating from the pump's back to the bucket ?

2. Would returning the fuel to the bucket cause a lot of air entrapment by the constant splashing ?

3. If the fuel is returned with a lot of pressre to the bucket, would it just splash right out of the bucket and not help at all ?


DD

DD,

I have been playing phone tag with Rickshotrod for 2 days. You have to go through there salesman to get a price.


As far as where I would return the fuel? I would attempt to tie it in with the regulated output of the Fass right near the tank bulkhead inlet that we custom install. This could cause to much backpressure on the Fass outlet though?

In regards to the fuel being heated . I do not think this will be a problem at all. I tested for 1 hour and the fuel gained 5F over ambient. I also monitored the Fass teststand at Bandimeres. It ran all day and never felt any warmer then outside temparature.

In regards to splashing and intefereing with the bucket? I keep trying to think of some type of diffuser. Like a screen or something?


Another option I attemted to research was the possibillaty of GM supplying a larger bucket? What do they use on there big trucks? The parts counter was very busy today so I left with my filters before gathering any real info.