[dmollner]

Well after about six months of burning B-100, my rubber fuel lines (as predicted) are weeping copious amounts of bio-diesel. I'd like to replace them with synthetic. Anyone ever changed all their fuel lines before? Any advice or instructions would be greatly appreciated.
Just in case anybody is wondering my truck is otherwise running very nicely on 100% bio-diesel which I purchase at the pump of a local gas station. I drive up, fill up, pay up, and drive away with a much cleaner burning fuel that is American grown.:cool2:

 

[78Chev6.2]

Diesel fuel hose

I have changed all my fuel lines using steel line and short lengths of fuel hose. I used the recommended fuel hose for diesel but I am unsure if it is fully satisfactory for bio-diesel.

The recommended fuel hose for in tank diesel use is SAE 30R10 which has the "special" coting all through the hose.
The recommended diesel fuel hose for outside tank use is SAE 30R9 (fuel injection hose) which is rated for 180 psi and has a thicker "special" coting to resist diesel fuel than the also acceptable SAE 30R7 (fuel hose) which is rated to 50 psi. The SAE number is stamped on the hose and the SAE 30R9 is CDN$4.50 per foot at my auto supplier.

The source of the above information is from Gates.

 

[High Sierra 2500]

I've changed almost all of the fuel lines on my truck. None of them are particularly difficult to change with the exception of the lines that go to the sending unit on top of the fuel tank and the line that goes from the fuel filter to the injection pump.

Just route them all the same as the old ones and reinstall all of the clamps that prevent the lines from vibrating and you'll be in good shape. Also, remember to bleed the fuel system out before you attempt to start the truck after you do any work on the fuel system.

All synthetic fuel hoses are compatible with biodiesel (basically, any of the new manufacture hoses - that's what has been used on most cars since 1996 or so). It's the natural rubber hoses that don't hold up, but I don't think you can even buy them anymore...

Hope this helps!

 

[jdemaris]

Well after about six months of burning B-100, my rubber fuel lines (as predicted) are weeping copious amounts of bio-diesel. I'd like to replace them with synthetic. Anyone ever changed all their fuel lines before? Any advice or instructions would be greatly appreciated.
Just in case anybody is wondering my truck is otherwise running very nicely on 100% bio-diesel which I purchase at the pump of a local gas station. I drive up, fill up, pay up, and drive away with a much cleaner burning fuel that is American grown.:cool2:

It would be nice if some day we could actually produce B100 without using foreign oil to do it. A lot of petroleum is used to produce, refine, and truck the crops and oils to make the B100.

I did a bit of testing and research on hose-life as did my son - who has access to better test equipment than I do. I assume you are referring to the return fuel lines that are approx. 1/8" or 3.5 mm i.d. unstretched. Good German-made hose is available in cut lengths from Volkswagen and Audi. Also the Italian diesel parts company Spaco.

After the testing we've done on various types of hose with several types of B100 and WVO, and high-heat over an extended period of time, we found the following.

Viton (hexafluoropropylene-vinylidene fluoride co-polymer) hose works the best and also costs the most. Buna-N rubber (Acrylonitrile Butadiene or nitrile rubber) is next best. Both versions I've gotten from McNaster-Carr hold up better than the OEM hose, made in China - that comes in the Dorman brand 6.2 diesel hose-kits. If you're going to be using a lot of fuels of questionable chemistry and acids, the Viton is by far the best choice.

The Viton hose is part #5119K41 at http://www.mcmaster.com/
It is $3.61 per foot.

The Buna-N hose with no sheaf is: 5235K42
43 cents per foot

The Buna-N hose with sheaf is: 5394K13
$1.40 per foot and is 9/64" i.d. insead of 1/8" but fits fine.

• High-Temperature Viton Rubber Tubing Soft, 1/8" ID, 1/4" OD, 1/16" Wall, Black ($3.61/foot)

• Oil-Resistant Black Buna-N Rubber Tubing 1/8" ID, 1/4" OD, 1/16" Wall Thickness ($0.43/foot)

• High-Pressure Black Buna-N Rubber Tubing 9/64" ID, 15/64" OD, 3/64" Wall Thickness ($1.40/foot This kind is jacketed—it looks like that VW tubing and Audi diesel tubing.

The Viton tubing is a little more stretchy than the unsheathed Buna-N tubing, but both are as elastic (if not more so) than the original return line. The sheathed Buna-N tubing is much more rigid than any of the others.

 

[dmollner]

a few more questions

Thanks for all the help, gentlemen. I'm going to get at it this weekend, if my schedule allows. A few more questions, if its not too much:
-Is there any hose that needs replacing between the fuel tank and the filter mounted on the fire wall?
-Also, is the same size hose used throughout this job?
-If not, what are the different sizes and where do they go?
-Anyone have a guess as to the total footage I'll need to do the job?

 

[78Chev6.2]

In Ontario Canada the fuel lines must be metal with no more than 1 foot of synthetic rubber hose at each junction to pass a "safety". The feed line is 3/8" from tank to filter. The return line is 1/4" from tank to injector pump.

So you need a foot of 3/8 and 1/4 from the fuel tank sending unit to the frame (mine started a little longer for ease of installation) where 3/8" and 1/4" steel lines can be routed to within a foot of the mechanical fuel lift pump. Connect 3/8 hose to the pump inlet and 1/4" hose to the injector pump metal return line just above the lift pump.

The output from the lift pump is metal and is routed up the front of the engine and under the intake manifold, exiting near the fuel filter on the bulkhead. A foot of hose is more than enough to reach the filter inlet. I put 2 hose clamps on every connection.

You will need 3 feet of 3/8 hose and 3 feet of 1/4 hose. I do not know how much steel line I used, maybe 12 feet of 3/8 and same of 1/4.

You may also want to replace the hose from filter to injector pump and injector pump return hose to steel return line. Then you only have the 1/8" injector return lines to worry about failing.

 

[GREASE FIRE]

i had the same problem, the gates fuel hose they sell at napa can not handle b100 even though it is the nitrile stuff jdemaris was talking about.
you will probably have to go with viton. I just got sick of it and stopped using b100, instead i cut some kerosene in with it as i did not feel like dropping that kind of money on viton and i run mostly grease anyway.

I did find that those short lengths of fuel line by the tank and connecting the steel lines along the frame rail were just fine. It was only the newer gates hoses i had added a while back that weeped.

i wonder if the nitrile stuff they sell at mcmaster is any different than the kind i got at napa - anyone know?

thanks,
Paul

 

[High Sierra 2500]

The questions "how much flexible fuel line will I need" and "is there any flexible line between the fuel tank and the fuel filter" depend on whether or not you have dual fuel tanks. If you do have dual tanks there are rubber lines at the tank switch which will need to be replaced and that will probably require three feet of line. In addition, you will need another foot or so of each size of hose to connect to the sending unit on the second tank.

Also remember that you will probably need to change the return lines on the fuel injectors unless you have already done so. As I recall, those use 1/8" ID hose. Depending on what type of hose you use you may or may not need clamps to hold the lines on. You will need about 6 feet of hose to do the job.

Hope this helps!

 

[scrambled]

I ordered all 3 sizes of viton from Mcmater-carr today around lunchtime. I have a couple of fuel leaks on the burb and my F250 has some weeping from the B100 on the lines I added for an additional filter. The hoses came this evening. These guys delivered in under 6 hours. Nice!!!

Travis

 

[dmollner]

Many thanks!

Awesome, gentlemen. I thank you for your expertise and willingness to help. What a great community this is!

 

[sleeping giant]

Sorry to join the discussion late, but I would recommend the Gates 4219 line for fuel hose. While Gates will claim they have no products in the US rated for biodiesel, in Europe they are more than happy to rate the 4219 line for biodiesel. The fuel line has a fluoroelastomer (CPE) lining, for low permeability (which gives it the biodiesel resistance).

http://www.gates.com/europe/brochure.cfm?brochure=2486&location_id=5165

This part # is available in the US as well. I bought some a year ago from a national distributor for gates products (I think they were in WA, i forget the name). It was well under $1 per foot (near $0.50), far cheaper than viton and also reinforced.