After my truck sits for 6-8 hrs. it is very difficult to start. It seems that the fuel is draining back to the tank and after 25 seconds of cranking it starts.
I can also start it by pumping it up with the lift pump. I replaced the valve on my injection pump but found no improvement. Is it my fuel line? If so, what line would it be and how do I diagnose the leak? Could it be a bad line in my fuel tank?

Does anyone have a piping diagram?

1996, xcab, auto.

Thanks
Kevin

 

You can do what I did over the weekend and replace all the lines from the tank up to the engine,I used a good marine grade fuel line and left all the factory lines in place.Once you have run the lines use the trick that somone here taught me and blow some slight pressure with an air compressor into the tank and prime the lines.Or you could chase the leak and repair it until you have another and another.......

 

The 24" section of 5/16" fuel hose is most often the problem but replacing it all the way to the tank as schoust decribed is the smart way.

Hose is in red below

 

After looking at what was left of my factory lines I could not get it done faster.boy I love this engine but the the rest seams to be rotting out very fast ,My 96 Gmc van had zero rot,the only problem is it only got 10 miles to the gallon.....

 

Update:
Yesterday I used my air compressor and a rag to pressurize the fuel tank and hopefully find a leak. I only pressurized to 50psi and found no leaks. Anyone got any idea's? I figured that if a fuel line was bad I would see fuel.

Thanks,
Kevin

 

50 psi sounds pretty high to me. i'd be careful doing that. i went with what others on this site have said and pressurized to 10psi to bleed out the lines and found i had a bad leak in the little elbow between the lift pump and pre-filter/heater. couldn't tell from the outside, but i cut it open and the inside was all rotted and cracked. my other lines were fine. probably had been replaced by p.o.

 

oh yeah,
here's another thought...
not sure if this is what everyone does anyway, but i went ahead and unattached the return fuel line from the metal line and dropped the end into a container while i pressurized the tank. seemed to me that if you are putting equal pressure on both the supply and return lines simultaneously by putting air in the tank, your not really pushing fuel through the system???

 

With 50 psi you're lucky you didn't split your fuel tank wide open.
What you have is a very small suction leak, not always possible to find where it's leaking outwards with pressure. High pressure may even seal the leak.

Save your self some time hunting for a leak and just replace the rubber lines. If they haven't been replaced yet they will definitely need it at some point.

 

Thanks for the suggestions, I'm going to replace the fuel lines and hope that it will solve the problem.
Kevin

 

what is the best line to go with for the money.
david

 

I had a similar problem except lost prime over night.....new lift pump cured it..

 

I have the same truck and had the same problem. Dealer changed the 24" of hose described by Infidel. Problem solved.

 

Coast Guard approved marine diesel line. It's twice the thickness of the oem line. If 4x4 it's easier to reach the rear of the fuel supply/return lines with driveshaft and starter removed. Now is also a good time to replace the starter contacts. When the contacts go bad they will take the starter with them. CTD starter's are not cheap.


http://fostertruck.com/dodge/default.htm