Engine/Transmission (1994 - 1998) fuel leak

[DPellegrin]

hey guys i have a 96 ctd with 50,000 miles on it it is a 2 wheel drive recently on a trip to wisconsin i noticed a fuel leak right under the drivers side kind of near the starter before i noticed it and when i arrived in wi the truck would not start it took several cranks to get it going anyways it did that every time i tried to start it also b4 i noticed the leak i took it to cummins and he said it sounded like my lift pump was going out so i tried changing the fuel filter today and now it seems like its not leaking and it has plenty of power also it starts right up anyone have any idea what is going on the mechanic said the lift pump might not act up when it is cooler out side today it was 50 yesterday it was 80 thanks guys

nick

 

[JohnE]

Nick;

Reads as the common fuel return line rot. It ages (don't we all) and finally develops pin holes that bleed air into the pump system.



Hmm warmer temps means warmer hose and more leaks.

 

[Joe G.]

Nick,



The hoses are most probably what is causing your trouble. However, there are other sources of air leaks. If new hoses don't fix it look for other places that can leak. The 12 valve lift pump is a pretty sturdy gadget and it ain't cheap.

 

[DPellegrin]

i looked under there today and saw that it is a metal fuel line with braided steel where it begins to curve up and it all looks like all one linefrom the engine to the tank should i replace the whole thing or cut it and put in just a section also should i replace both lines which one do you think is leaking?

 

[Joe G.]

There are some hoses. They are clamped to the steel lines. Big PITA to change. While you are in there it's a good idea to change the supply and return hoses. Sometimes when they are bad they leak from the end. The fuel runs down the line and drips off the braided steel part. The hoses are above the starter. You have a vacuum brake booster so you can remove the nuts that fasten the master cylinder to the booster. That will allow you to lean the master cylinder toward the fender and give you a little more room to work on the hoses. Removing the fuel filter helps too. The steel braided hoses are probably ok, but you should clean up things and watch it while it's running to make sure where the leak is.