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Fuel Lines through frame rail? Bulkhead ideas?

6K views 3 replies 2 participants last post by  carcrafter22  
#1 ·
Guys I'll be running rubber fuel lines the entire way, but I was curious on how I should go through the frame rail since I have saddles tanks that sit outside the frame rail..... I cannot find barbed hose fittings that have a barb on each end and a threaded body that I could use for a bulkhead fitting.... (AKA rubber hose vibrating on a metal clearance hole spells bigtime leak within a few miles of vibration.....)

Anyone tackle this yet?
 
#2 ·
Just gonna throw this out there, PLEASE dont run rubber the whole way! Hard line is so cheap and easy to use its insane not to use it, you can get 25' and 50' rolls from summit for so cheap its crazy, just get the aluminum setup and be done with it. If you get the aluminum you can run tube and nuts on each end after flaring them to attach to the gas tank and get some of those rubber insulated clamps from home depot, I just drilled and tapped my frame for some really small bolts (maybe 1/4" will work also).

If your deadset on the rubber and all the possible headaches that come with it (ask me how I know and why I will NEVER run all rubber on a diesel again) then get something high quality (read expensive) and stay away from aeroquip pushlock hose it dry rots with diesel fuel. You can run push lock fittings on the ends, go with some 3/8" feed line with -6AN or to save money go to a plumbing supply and get standard steel -6 JIC fittings for the returne 5/16" line will be fine and you can run a -4 an or jic fitting, you can also run 3/8 for both sending and return if you want.

For the through the frame part, it will help you to run an or jic fittings agian. You can buy a "bulkhead fitting" from summit, jegs or any large plumbing supply that is fairly long and double male with a jam nut to hold it in place.

http://www.google.com/imgres?imgurl...bnw=124&prev=/images?q=jegs+bulkhead+fitting&um=1&hl=en&sa=G&ndsp=18&tbs=isch:1

Also please please please stay away from hose clamps as much as possible to save yourself some headache, I had a problem with my ford/ isuzu setup when I first got it running, it would start then die I chased that problem for 2 days with all good tight connections, finally after going through it all I tighted the right fitting till it was about to break the clamp and it worked for a while then once it loosened backup I had the same problem. After going to all AN or JIC fittings that I could tighten up with a pair of wrenches I never had that problem again.
 
#3 ·
Only problem is that my saddle tanks have 90* barbed fittings welded right onto the top of the tank (which is also part of the pickup tube as well) so I'm stuck with that.... but I could transistion right away. As far as aluminum hard line..... how did you make the connection from hard line aluminum to softline rubber? (inverted flare fitting to ?)
 
#4 ·
The easiest way is to just push the hose over it but its also the worst way to do it.

I prefer to run as little rubber as possible. You can always run a short amount from the barbed fitting into a pushlock fitting with an -AN or JIC fitting on it then into a double male fitting that connects to the hardline, anytime yuo connect hard line to anything using AN or JIC fittigns you will need to flare the line and run a tube nut and sleeve. When you use these type of connections you are pretty much gaurenteed to have sealed connections and never have to worry about it.

On my ford I welded fittings into the fuel tank so I could connect AN fittings to it with about 6" of goodyear rubber fuel line (so its easy to move if I need to remove the fuel tank) then used AN connections to get it to aluminum 1/2" fuel line then AN fittings to connect to the fuel filter head back into 1/2" hard line and finally back into 6" of rubber line at the injection pump to keep vibrations seperate from the engine and fue line. Point is I have all 100% solid connections (so no more air in the fuel problems for me) and very minimal rubber to dry rot some day. You also have to remeber some stations these days are starting to offer biodiesel and in some cases it can eat through rubber fuel line. Of course it depends on how much biodiesel is mixed in and what kind of fuel line. The other things is this, I would have never suspected a high quality line like qeroquip to actually dry rot after only about 4 months but it sure enough did on my dads 06 duramax powered chevy, we replaced it with some high quality 100% biodiesel rated fuel line and after a year still no problems. Just one of many reasons I use as little rubber fuel line as possible.