fuel line replacement

[Headshot zod]

There seems to be of info on fuel line replacement here. Is there any reason I can't just run a new line and forget about the swively thing on the end. I'm wondering if that is causing me all my fuel problems. Perhaps my B100 usage destroyed the seals since they are original lines. I went to the dodge dealer and the said I need to go aftermarket. Any bright ideas.

 

[swankmetal]

you're talkin between the tank and lift pump, eh? i've been wondering the same for a while now. maybe somebody like ronA will pipe up on this one. definitely interested in what comes about on this.

 

[Headshot zod]

That would be the one. I was reading that when this line fails in 2nd gens it sucks air rather then leak. I've had this huge problem for almost a year and I wonder if this may the issue.

 

[MLKramer]

The line between the tank and the lift pump on my 1st gen. rusted until it got a small hole in it. The truck got harder and harder to start (sucking air) and just about wouldn't run at all by the time I figured out what was doing it. New line, no more problem. It never did leak fuel out on the frame or the ground, just sucked air while running. Hope this helps.

 

[Headshot zod]

Was replacing the stock lines a pain. Meaning did you remove the body, or did you drop the tank? Or did you manage to get your hands in between the frame and the tank.



I'm losing the prime on the truck more now and the novelty of priming it has warn off. Today I couldn't hand prime it at all.

 

[MMiller]

I would run a new line. I pulled the tank down on my 90, and the steel line was ready to rust in two, where it was unable to be seen between the tank and frame. I'm suprised the truck actually ran.



I don't see any reason that running a new line would be bad, however I learned on my old 75, that running a rubber hose from the tank to the pump was a bad idea. It would run out of fuel, I believe either the line would suck shut, or it would suck air. I went with a pusher pump back at the tank and solved the problem.



On my 90, I ran as much hard line as I could, then I have a short section of rubber hose, and clamps, linking the lines together. I put a fuel cell up in the bed to protect it from offroad rash.



I don't know how the lines hook up on a newer truck, but on the 90 there was just a short section of rubber hose with clamps hooking the tank to the steel line on the frame.



I hope this helps... ... ...



Michael

 

[Headshot zod]

Thats actually a great answer. So I guess I'll just pick a replacement line. I am not looking forward to dropping the tank. It since it looks like I need to drop the carrier bearing. What a mess...

 

[MMiller]

Thats actually a great answer. So I guess I'll just pick a replacement line. I am not looking forward to dropping the tank. It since it looks like I need to drop the carrier bearing. What a mess...

Depending on what you want to do, I just used 5/16" brake line, then 5/16 fuel hose and clamps. Make sure and find hose that will tolerate diesel fuel. Philip suggested DOT air hose, dunno if you can find it 5/16" though. It all matched up nice with the existing line that was clean.



On my 90, I really don't know if the tank needed to be dropped to add another line. I'd be temped to thread the steel line up the frame rail, and let it hang the 8-10" between the tank and frame. Any truck that has spent time in Iowa or Illinois the straps probably aren't comming off without a torch anyway.



Michael

 

[Headshot zod]

well, despite the fact the dealer said the parts were available aftermarket, they weren't. So I guess I'm going with the brake line and hose now. Did you have flare the line at all or did you just clamp the hose with a hose clamp.



And going into the lift pump did you use a brass fitting like the ones that go into carbs. If so what thread on the lift pump end?



thanks.

 

[MMiller]

My 90, must be significantly differnt then the newer trucks. My truck had a hard line up the frame, and then at the engine it went back to rubber hose and clamps. There is also a nipple in the lift pump that the hose slides over and clamps. I believe this is factory, as it had those interesting clamps that use the screw and the nut, that you can only tighten so tight. Last night, I removed the hose between the frame and the lift pump, installed a new hose, and then put a inline filter in for now. The fuel cell company said that there could be stuff in their cell, I'm glad I put the fitler in, after startup the filter filled with steel shavings/filings, from the lines. Glad it did not make it to the lift pump.



Anyway, I did not flare the line, the clamps should be adequate. I don't know what the thread is on the lift pump, I will see if my lift pump was made with a nipple, or if it threads in, tonight.



Michael

 

[Greenleaf]

Most of the school buses use the DOT air brake hose. It's a semi hard plactic tube. It's found at any truck repair dealership and probably NAPA. You then purchase as much as you want and buy the fittings which vary in the hundereds in terms of shape and thread size. It's found in sizes from 5/16 (or smaller?) to..... ??? BIG.



Just for giggles, walk into an Auto Zone and ask for DOT air brake tubing... ... ROFLMAO



The fittings are reusable outside of the brass ferral and insert which is crimped onto the line when you tighten the nut. If your livn' right you can sometimes pull a fitting off and reinstall it.



The buses use 1/2" suction and 3/8" return. Red for suck and green for re-run fuel. Yes. They are in many different phyco cool colors.



The 92 turck of mine has this hard plastic DOT type fuel line.

 

[swankmetal]

what size might that "DOT type fuel line" be, scott?

 

[Ggg]

Thats odd that School busses are using air brake line for fuel. School busses are safety checked rather closely. I know DOT air brake line is not NTSB approved for fuel. I also know from first hand experience that at a roadside safety inspection the Secretary of state cop red tagged a truck for using air brake line as a fuel line, I was the service tech that went out on the call.

 

[Greenleaf]

In OHIO it must be OK to do so as MANY of the school buses are DOT air line equipped for fuel. The buses are inspected by the OSHP frequently and each bus must be built to each state paramiters.



Dave, What size is what fuel line? ... ... ... ... ... . My truck? Our former President would reply " I don't recall at this this time". It's possible it was supplied from the factory this way. I didn't install it.

 

[RWWinslow]

Fuel line that works on diesel fuel in this application in our trucks is either rated "marine use - USCG Approved" where USCG means US Coast Guard or fuel line rated for "fuel injector service - all fuels" . The latter is about $13 per foot but in this particular case you get what you pay for. . . . I have also looked at one B engine where the fuel line between the lift pump and the filter started to fail in such a way that it sucked air when shut down but did not leak when the engine was running - go figure!



Good luck -

 

[Headshot zod]

I thought I saw a link to a marine fuel place somewhere on the TDR but I can't find it.