The problem:

Unlike the LB7, the LLY has a closed PCV system where the crankcase is vented back into the intake tract. There are multiple issues this design creates in the Duramax.

-Hot crankcase vapors interfere with a fresh, cool intake charge

-The system allows oil liquid through the intake, coating many parts of the intake system, including the turbo, intercooler, and all connections. Some LLY owners have experienced oil contamination to the point of oil leaking from the intake tract, most notably near the intercooler.

-The possibility oil coking in a warm turbo, interfering with its performance.

The solution(s):

I designed a small 10" by 3" canister that acts as an oil separator in the PCV system. The vents on each side of the Duramax come together into this cylinder, where oil collects at the bottom, and vapors exit the top.

This allows for two approaches.

The system can remain a closed PCV system, but still reap the benefits of keeping the majority of the oil out of the intake tract.

-or-

The system can become an open PCV system, where the top of the separator vents to atmosphere through a small breather filter.

From an emissions stand point, I consider my truck "off-road" and I vent mine to the atmosphere. This allows me to avoid any oil contamination, as well as an untainted air charge.

I am considering building these and selling them to board members that are interested. I need some feedback on the interest level for a product like this to decide if it's worth doing. If the interest was there, I'd like to make both a closed design, as well as an open design. This way, people concerned with emissions standards would still reap the benefit of less oil in the intake, but still maintain a closed system. On the other hand, those that would rather vent to atmosphere, as in the LB7, would have that option as well. As stated earlier, the open system would employ a filter, which, in negative pressure situations, such as when the crankcase cools after shutdown, would provide a clean charge of air.

The canister will hold nearly 500ml or 1/2 quart of liquid before interfering with its functionality, and has a drain at the bottom that has a barbed fitting to allow for attachment of a standard 3/8" fuel line to drain at any time, perhaps at each oil change.

At this point, it's looking like the cost would be around $75 for either system... This would provide all pieces necessary to complete the conversion including hoses, clamps, fittings, and the canister. The canister is constructed out of oil resistant PVC plastic.

The canister should be mounted anywhere that the drain can be at least 45 to 90 degrees opposite of the top where the breather or fitting back to the intake sits. I have mine mounted along the drivers side frame where it's easy to zip tie to the wire harness. It's also easily accessible to drain from underneath the truck. There are 3 simple connections, as seen in the pictures below. At the top, the closed system will have an exit fitting back to the intake. On the open system, there will be a fitting with breather filter. On the side, near the top, is the entry point for the crankcase ventilation... a simple 3/8" hose fitting. Here is where the vapors / liquid will enter, and the liquids will settle to the bottom, while the vapors will go out the top. Lastly, at the bottom, there is a simple valve with fitting to allow for drainage.

My results:
I changed my oil at a 5k mile interval, and after running the PCV reroute and canister, I drained about 4 oz of oil... this may vary in other trucks, but that's how much would have been circulated back through my intake tract. Before I installed this, and my main reason for developing this, I had the notorious leak at the intercooler boot.

Pictures of the canister are here (this is the open system)

http://www.spectrixdesign.com/SS/1.jpg (http://www.spectrixdesign.com/duramax_pcv/1.jpg)
http://www.spectrixdesign.com/SS/2.jpg (http://www.spectrixdesign.com/duramax_pcv/2.jpg)
http://www.spectrixdesign.com/SS/3.jpg (http://www.spectrixdesign.com/duramax_pcv/3.jpg)
http://www.spectrixdesign.com/SS/4.jpg (http://www.spectrixdesign.com/duramax_pcv/4.jpg)
http://www.spectrixdesign.com/SS/5.jpg (http://www.spectrixdesign.com/duramax_pcv/5.jpg)
http://www.spectrixdesign.com/SS/6.jpg (http://www.spectrixdesign.com/duramax_pcv/6.jpg)
http://www.spectrixdesign.com/SS/7.jpg (http://www.spectrixdesign.com/duramax_pcv/7.jpg)

So, in closing, this worked really well for my truck and it was suggested I share this with the board... After speaking with Nick and presenting this idea, he said it would be ok to start up a limited vendor status... I wouldn't mind that at all, but I'd like to gauge the interest first.

What kind of interest would there be for a product like this?

Would there be interest for both a closed and open system?

Thanks!

I vote for open.

I would be interested in the enclosed system

I'll try one. I also want to add that those of us that tow hard and run higher boost will have more crankcase pressure making this even more important!

i would go for the open system, just wondering how the open system would work in a off-road wheelin situation. would the filter get clogged after getting caked with mud? do you think it may be an option mounting in engine compartment and running a drain hose down to frame rail? i think it is a great idea and would purschase one. :) GREAT IDEA :)

I would be interested in the closed system. Neat idea.

Jim

I'd be interested in the closed system.

I would also be very interested in this system, especially since most my use with the truck is towing!!!

open system

I'd like a system also. Don't quite understand the in's and out's of open or closed system, but I know I don't want the crankcase vented back in to the intake.

I'll try one. I also want to add that those of us that tow hard and run higher boost will have more crankcase pressure making this even more important!

Absolutely.

i would go for the open system, just wondering how the open system would work in a off-road wheelin situation. would the filter get clogged after getting caked with mud? do you think it may be an option mounting in engine compartment and running a drain hose down to frame rail? i think it is a great idea and would purschase one. :) GREAT IDEA :)

I go off road every so often... I've checked it pretty regularly, after big rains, or after going off road... I've never noticed the filter getting much dirt or even water on it... Here's a link to some pictures of it installed... I took these tonight, and that's after driving in some serious rain...

http://www.spectrixdesign.com/duramax_pcv/5.jpg
http://www.spectrixdesign.com/duramax_pcv/6.jpg
http://www.spectrixdesign.com/duramax_pcv/7.jpg

In addition, the filter is easily replaced! But yes, I agree... if you are really into off roading and want to be extra careful, you can mount it anywhere you'd like... and the drain has a fitting so you can put any length of hose you choose for a drain.

I'd like a system also. Don't quite understand the in's and out's of open or closed system, but I know I don't want the crankcase vented back in to the intake.

I may not have explained myself very well... Those concerned about emissions may use the canister "in between" their current system... just to remove most of the oil from the vented gases... but the system still vents into the intake, keeping it emissions legal. The difference, however, is you won't have as much problem with the accumulation of oily deposits in your intake tract.

The open system, however, separates the oil and vapor just the same, except the vapor vents to the atmosphere through the filter. A lot of people just vent the PCV to open air, but you can introduce contaminants into the crankcase this way, and you also leave oil stains wherever you end up running the hoses to. This kit, in either form, avoids both.

close system:grd:

When do they go on sale? :D

When do they go on sale? :D

:) If enough interest is there, I don't see if being too long from now. I'm excited that I can actually share something with everyone on here that's worked so well for me.

Have you gone through an automatic carwash with the underbody flush? I'm interested to see how soaked the filter would be as I frequent these washes.

But.... the filter can dry right? So would this even be that big of a concern?

Put me down for the open system. (really; put my username on a list or something... I want one ASAP)

Have you gone through an automatic carwash with the underbody flush? I'm interested to see how soaked the filter would be as I frequent these washes.

But.... the filter can dry right? So would this even be that big of a concern?

Put me down for the open system. (really; put my username on a list or something... I want one ASAP)

I can't say that I've been through a auto carwash with undercarriage flush since I installed the kit... Although, besides mounting the canister in such a way that gravity can effectively keep the liquid down, the mounting location is trivial. What I would suggest, is that you mount it in a location suitable to your driving habits and/or style. In my case, since I don't off road a whole lot, at least no deep water, and I don't go through automatic car washes, the drivers side frame (as pictured in the earlier posts) was an optimal place for me. Especially because it's so accessible to drain on oil changes... it's right next to the oil filter...

In the end, while water may not effect the filter that much, and it may dry fairly quickly, I would try my best to keep it in a somewhat safe / dry place.

It should dry very quickly anyway, so unless the water pressure blasts it off, its not an issue.

.

I'd be interested in the open system.:ro)

I'd be interested in the closed system.

It may be advisable to review the recent articles in "PCV Re-Route" in the "Do it Yourself" posts. The one I installed yesterday and today is very similar to what I assume you are planning on doing. I'm pretty happy with how it worked out.

closed

Since mine is used mainly to tow ,I'll take the closed. Mike:)

Might be interested in an open. Emissions laws be dammed!

I like the closed. Can I get mine in stainless instead of pvc? :ro)

I like the closed. Can I get mine in stainless instead of pvc? :ro)

Yaz, unfortunately I am not set up for metalworking... however, there are some out there on the market... problem is, they are at least twice as much as the projected price for the PVC construction... although, for those who wanted to mount them under the hood, it would look nice.

Although, your question makes me consider offering different colors... you can even paint match chrome...

how long til you can produce?

great idea!!! Id definetly consider purchasing one...

Now if you could set it up to return the oil to the crankcase.....
:rolleyes:

how long til you can produce?

I am still working through some of the logistics of making several of these at a time... the interest looks like enough to cover what it will take to make a few, so hopefully I'll be set up in the next few weeks.

Now if you could set it up to return the oil to the crankcase.....
:rolleyes:

Well, to be honest, I really considered that at first... after running the system 5000 miles and only collecting about 4oz (which, 4oz. is substantial running through your intake, but not enough to worry about losing), I decided against it. To me, it's definitely not worth provisioning, unless there is the fitting left over on the LLY from the LB7... which, I don't think it is....

Yaz, unfortunately I am not set up for metalworking... however, there are some out there on the market... problem is, they are at least twice as much as the projected price for the PVC construction... although, for those who wanted to mount them under the hood, it would look nice.

Although, your question makes me consider offering different colors... you can even paint match chrome...


I'm sure you can get the HD PVC in Dark Grey and not have to paint it at all. I was just thinking about a cooler one they everyone else.. That's what's cool about customizing our rigs. I'll just turn a new canister on a lathe to make mine different if I get ambitious. It's handy having a nice brother that runs a machine shop.

Great idea, thanks. I'd be interested in the closed system as well.

I have a question though... since I also have suffered from the IC boot popping off and leaking due to this oil going back through the intake track... how much oil do you guys think is actually inside the intercooler right now???

If this mod is done I would also suggest cleaning out the intercooler with something that will break down oil inside of it and not harm anything in the process. In other words, remove the IC and clean it out thoroughly. There is no telling how much oil is just sitting at the bottom of the IC over an extended period of time.

how much oil do you guys think is actually inside the intercooler right now??? .

Probably a lot...-:t

I shut my EGR off at about 15,000 miles and thoroughly cleaned the intake then. I took it apart at like 20,000 to install the new turbo and it was covered in oil and sludge again.-:t

Ben

i believe the oil in the intake is an "add" to our overheating issues. I also believe that under extreme usage that oil is sucked back into the motor and burned.

I've been running external PCV on Casper for quite awhile now.

I recently put it back to stock. I never dyno tested with it On and Off.

If a PCV does not have a catch can, it is a violation of NHRA tech rules.

It's a good idea.

this is kind of funny to me, but most of the folks that say they are using tons of oil in their LLY can probably find it all in the intercooler!! LOL... as Rick mentioned it gets sucked back in and burned. I'd rather keep the oil in the crank case where it belongs.

When this becomes available put me on the list for the close loop system.

also when I install this I am going to remove the intercooler and see just how much oil is in it.

For those concerned about Water, dirt getting into the filter I have a solution
We use it on snowmobiles and it works quite well
This is a link to the material Pre-Filter raw material (http://startinglineproducts.com/catalog.cfm?pageID=detail&catalogID=3&catID=21&productID=367)

And here is the link to the pre-filter cut thats set up to just slide over the filters
Pre-Filter Cut to fit already (http://startinglineproducts.com/catalog.cfm?pageID=detail&catalogID=3&catID=21&productID=372)
The part is 14-226 Pre-Filter for Uni-Filter Snow Filter 17.90

It slides over the filter and is completly water proof. It has elastic band to keep tight over the filter. Works nicely

PVC. I can bend pvc at a fairly low temp. It also becomes very brittle after repeated thermal cycles, just some food for thought.

I too would be interested in a well thought out, return to sump, breather. No messes.

PM'ing one other thing to consider.

Yaz, unfortunately I am not set up for metalworking... however, there are some out there on the market... problem is, they are at least twice as much as the projected price for the PVC construction... although, for those who wanted to mount them under the hood, it would look nice.

Although, your question makes me consider offering different colors... you can even paint match chrome...

I just wanted to offer a comment about mounting this under the hood. I already made my own system, similar to yours with a filter on top as the breather. When I mounted it under the hood, I found that the oil wasn't condensing out of the vapor before coming back out of the breather. Thus, no oil in can, oil soaked breather/filter and mess in engine compartment. The engine compartment is pretty hot even under normal operating conditions. When I had an Edge, it would routinely show 192 degrees under the hood. My can is aluminum, so maybe it would absorb more heat than PVC. Anyway, I extended the hoses and moved it to the front bumper area and no more problems.

I just wanted to offer a comment about mounting this under the hood. I already made my own system, similar to yours with a filter on top as the breather. When I mounted it under the hood, I found that the oil wasn't condensing out of the vapor before coming back out of the breather. Thus, no oil in can, oil soaked breather/filter and mess in engine compartment. The engine compartment is pretty hot even under normal operating conditions. When I had an Edge, it would routinely show 192 degrees under the hood. My can is aluminum, so maybe it would absorb more heat than PVC. Anyway, I extended the hoses and moved it to the front bumper area and no more problems.

Did you have any additional oil/air separating mechanism within your canister? That may be where ours differ... I have had over 5000 miles on mine and the filter is still red, with no oil deposits... and plenty to drain. I'm not saying that it was totally free of any oil vapor, but certainly not enough to make it past the filter.

Check out these links. It may be easier to utilize & modify something like one of these rather than starting from scratch.

http://cgi.ebay.com/ebaymotors/OIL-CATCH-RESERVOIR-TANK-CAN-SL-UNIVERSAL-FIT-ALL-CARS_W0QQitemZ8049480675QQcategoryZ33556QQrdZ1QQcm dZViewItem

http://cgi.ebay.com/ebaymotors/OIL-CATCH-RESERVOIR-TANK-CAN-FOCUS-CAVALIER-CAMARO_W0QQitemZ8049764776QQcategoryZ46098QQrdZ1QQ cmdZViewItem

http://cgi.ebay.com/ebaymotors/GREDDY-OIL-CATCH-RESERVOIR-TANK-CAN-MUSTANG-PROBE-NEON_W0QQitemZ8049468669QQcategoryZ33556QQrdZ1QQcm dZViewItem

http://cgi.ebay.com/ebaymotors/OIL-RESERVOIR-CATCH-CAN-TANK-ALTIMA-MAXIMA-FRONTIER_W0QQitemZ8049825965QQcategoryZ46098QQrdZ1 QQcmdZViewItem

I definitely can't compete with that price... but, I know what works for me on my truck... I can't say with 100% accuracy that it will work for every Duramax out there, but I thought I'd share anyhow.

They all look to be pretty much the same. Same builder and different sellers? And Duramax2500HD, don't know if these will work in a DMax.

Jim

Closed System Sounds Interesting

They all look to be pretty much the same. Same builder and different sellers? And Duramax2500HD, don't know if these will work in a DMax.

Jim

I modified the square Greddy type can in one of those links. The can was about $35 by the time I got it to my door with the shipping. Then had to add a breather to the top, make a bracket, put some baffling inside (it had none), change out a couple of fittings, drill and tap some holes, etc. Then, as I posted above, it didn't work for sh*t under the hood. By the time I was done screwing around with this thing, I easily had more than $75 in it. If Duramax2500HD's proposed system saves you all that hassle and running around and works, it's a pretty good deal IMO.

Edit: I added a pic of this thing. It's mounted to the right of the driver's side tow hook (inboard from the tow hook). I just used the bolt that was already there and put another nut on it to hold the bracket.

17231

The shipping in the ebay auctions listed above is way too high (more than the product itself), but there may others with more reasonable shipping.

Also, there are evidently OEM oil separators used on the LB7. I'm not sure how much they cost.

Post #13: http://dieselplace.com/forum/showthread.php?t=70582&page=2

They shipping in the ebay auctions listed above is way too high (more than the product itself), but there may others with more reasonable shipping.

Also, there are evidently OEM oil separators used on the LB7. I'm not sure how much they cost.

Post #13: http://dieselplace.com/forum/showthread.php?t=70582&page=2

True... and the LB7 separator was one of my original ideas... but if you didn't plumb the oil line back into the crankcase, you'd still need a canister... that's why I decided just to make my own separator with reservoir and drain...

Now if you could set it up to return the oil to the crankcase.....
:rolleyes:

The LB7 does this sort of. I never really studied it in detail, but there is a hose and what looks to be a check valve in it that runs to an area near where a small block would have a fuel pump. The "collector" is part of the alternator bracket assy and the vent is simply a draft tube. There is some oil loss through this and we generally extend the tube with a piece of hose to keep things cleaner.

The LB7 does this sort of. I never really studied it in detail, but there is a hose and what looks to be a check valve in it that runs to an area near where a small block would have a fuel pump. The "collector" is part of the alternator bracket assy and the vent is simply a draft tube. There is some oil loss through this and we generally extend the tube with a piece of hose to keep things cleaner.

If i'm not mistaken, the oil that is effectively separated in the canister runs back to the crankcase, correct?

In the LB7 diagrams I reviewed, there was a drainback... was it not like that on all model year LB7s?

Yes.

2001 I believe had a plastic tank, and 2002+ had it as an integral part of the alt bracket I believe. Fortunately I have not had to tear into any of this stuff yet...

If i'm not mistaken, the oil that is effectively separated in the canister runs back to the crankcase, correct?

In the LB7 diagrams I reviewed, there was a drainback... was it not like that on all model year LB7s?

The diagram that I posted was from my 2001 service manual and the way the system is installed on my 2001, I can't vouch for anything after that.

I would be interested in the closed seystem

Cannister............ another place for a Fumoto!

I'm in for an open system. When does it get here?:)

Cannister............ another place for a Fumoto!

That was my original thought, as well... but it would drive the price up a good bit...

If indeed the newer trucks still have the place for the oil drain back it would be easy to custom tailor that into this system.:)

I'm working on my own setup.

One qt. can with sightglass. Cost?, about $24.00

Will post pictures of finished product.

Will work open or closed. Here's a pic of what I'm going to use...

Regardless of what you use for an accumulator, there is an easy way to tap into your existing PCV plumbing. Pictures are included - "Do it yourself & Useful articles" - "PCV Re-route". I suppose you could run the new hose down to the original port below the alternator bracket that the LB7's used thus draining the oil back into the crankcase. If anyone has looked to see if that port still exists on the LLY's - please let us know.

I suppose you could run the new hose down to the original port below the alternator bracket that the LB7's used thus draining the oil back into the crankcase. If anyone has looked to see if that port still exists on the LLY's - please let us know.

I will be checking tonight on this when I get home.

I imagine the factory has this blocked off, (not drilled out), if the casting is even the same as the LB7. If that's the case, then we will need some input from someone with an engine that's apart. I'm not going to ''blindly'' drill a hole without knowing what's on the other side.

I think Fingers still has one in pieces.

This sounds like an excellent product. I'm definitely interested.

So you Gonna do this or not?

i'm just curious as to what you guys don't find appealing about dumping it straight to the ground via some heater hose running right off the valve cover breather?

i'm just curious as to what you guys don't find appealing about dumping it straight to the ground via some heater hose running right off the valve cover breather?
The reason is why the PCV was added to an engine to start with. Over the years the engines have started to develop more and more crankcase pressure. Our high cylinder pressure creates even more pressure. The PCV was added in an effort to keep from blowing gaskets out. In a drag car you use a crankcase evac kit (it works in much the same way only uses the exhaust for the vacuum), or a vacuum pump to create suction. Tests by major engine builders also claim HP increases by evacuating the crankcase properly.

don't the LB7's vent right to the atmosphere?

i'm just curious as to what you guys don't find appealing about dumping it straight to the ground via some heater hose running right off the valve cover breather?

Uhhh, .... $6000 for a new concrete driveway and sidewalks at my house. That's why!

Plus the fact that at 75mph the oil has got to end up on the underside of the truck. That, mixed with dirt = yuck. Of course for you guys in the wintry North, a little more corrosion protection might be a benefit! :lol:

So you Gonna do this or not?

I keep having concerns about liability... these days, you can't be too careful. Just trying to make sure I have all my bases covered. Hopefully, I'll know in the next week or so.

Thanks

don't the LB7's vent right to the atmosphere?

I still have an LB7 truck also. If no one else pipes up I will check it when I get back home to see.

My 2001 LB7 vents to the atmosphere, but through a plastic separator that then gravity drains oil back to the block through a hose connection.

Diagram is here in post #13

http://www.dieselplace.com/forum/showthread.php?t=70582&page=2

what does the cummins do? a friend of mine has a 95 that vent into open air like mine now but i dont know if he did that or not.

i will probably go with this guys setup, i just did mine this way to keep it out of the turbo until a less messy method pops up.

Just left my dealer mechanic. He said all LB7's had no PVC. LLY was the 1st for it. hhhmmmm....:)

I think that you would need some type of baffel or oil seperator, so the filter on top of the canister does not fill with oil. With out controling the oilly vapors too 85-90 % clean, it will just be putting back what you were trying to take out. :confused:

Do you use oil resistant glue ? Also what are the temp ranges for the PVC ? It is a nice idea.

Our trucks, (LLYs) don't have the drain back nipple like the LB7s. They don't even have the boss cast in it (at least mine didn't). So, I will just every so often, drain the oil from my 1.5 quart bottle.

To answer the Heater hose to the atmosphere trick... I don't want oil stains all over my new asphalt driveway!!! The DCensored ED intercooler hose is doing that now!

Change # 49. I'll eventually get it so I'm comfortable with covering all contingency bases. The articles in the "Title" show many members solution or at least approaches to keeping the crankcase blowby out of the turbo and CAC.

OK I am getting the pieces to do the pcv mod. Question I have is what should I do with the oil already on the turbo and in the intercooler since I see mine dripping. Take it all apart and clean? Leave it alone? Just clean what I see? If I clean What do I use to clean it off? Thanks Mike

I keep having concerns about liability... these days, you can't be too careful. Just trying to make sure I have all my bases covered. Hopefully, I'll know in the next week or so.

Thanks

Any progress on the PCV front?

Unfortunately, I think its dead... the liability is too great. It may be best to leave it as a DIY mod considering the problems you could face if not properly maintained such as the vent getting clogged and leading to seal leaks, etc...

If anyone has any questions about the setup, just let me know.

Thanks for the interest!

Bummer!

I was ready to buy a turnkey solution.

I think the extra oil in the turbo is making the OH issues even worse. I know that when my turdo sand car is running rich all that extra fuel in burning in side the turbo and makes everything super hot. I even added an Oil Cooler on it and it barely made a difference. Re-mapped the ECU and leaned it out and it ran super cool.

Oil buring in the turbo must create more heat.

So does anyone have a easy solution for the PCV?

Pyle

Unfortunately, I think its dead... the liability is too great. It may be best to leave it as a DIY mod considering the problems you could face if not properly maintained such as the vent getting clogged and leading to seal leaks, etc...

If anyone has any questions about the setup, just let me know.

Thanks for the interest! Why not research the OEM LB7 stuff a little more. If you can duplicate it on a budget you should be good to go.:)

Thanks guys. I guess I'll :grd: using the DIY section.