My fuel tank is leaking badly. I mean like a drip drip drip deal. Only when the truck is runing and after i shut if off for a little while. ITs coming fromt the top, but I havne't had the chance to check it out yet. Maybe tonight, but it sucks working in 10 degrees outside in the dark.
Any suggetions as to what it could be?
Whats up on top of the tank? what to look for? I know theres a fuel line to the lift pump, and a return line. but what about a vent line, rollover and such
Thanks
Josh

 

If it's leaking only with the truck running, I'd suspect the return line is the problem.

 

Here, a lot of this was covered in this thread...

https://www.dieseltruckresource.com/...t=Leaking+tank

Hope that helps...

 

thanks for the help guys. I think the most helpful ost was the suggestion to lift the truck bed rather than drop the tank. My tank is pretty full....that is....is it hasn't all leaked out....
Josh

 

Heres what the top of your tank should look like https://www.dieseltruckresource.com/...cat=500&page=1

All of the chewing gum stuff was put on there from the previous owner trying to fix the rusted fittings coming out the top of the tank mod. The closest one has a pin hole in it allowing it to leak after shut off and and cause a hard starting. I didnt feel like doing a pro-fix yet so i just lifted the bed, scraped all the old crap off the lines, put on some new permetex epoxy that is diesel compatable. Leak is fixed going on about a year now. Good luck

 

DZLPWR.....What is the plastic fitting in the upper left corner of your photo ?

 

I had the same issue as dzlpwr. I removed mine and brazed it up. You can't buy just the fitting. You have to buy the whole fuel module, but you can get a reman one for about $125. I am planning to modify it, I'm thinking about using a "firewall pass through" type fitting, and running new fuel lines with the AN fittings, and running the return line into some where else. When you pull yours, measure the hole and let me know its size. Thanks.

 

That black fitting with what looks like a hose barb on the end? Never was hooked up to anything so id assume its a vent or c/v of some sort.

PS: FWIW The way i pin pointed my leak was i pressurized my tank through the fill hose with a raq wrapped around a rubber hose and clamped tight with hose clamp, also block off the overflow tube in the filltube. Used an air nozzle to pressurize it just a little and directly pin pointed the problem area.

 

Racer9 - Do you have a source or p/n for a remanufactured module that you refer to? I'm working on a similar issue, but don't want to drop my tank and remove the module to figure out how to repair since it is my daily driver and I work slower than mollasses in January... Thanks for any help you can provide.

Will

 

Sorry, no p/n. I was visiting with my friend, who is the parts manager at a dealership, and he told me about it. I found it easier to lift the bed to get at it.