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BWT95K2500
08-02-2006, 19:10
Okay, 1995 Chevy K2500 non-turbo

Truck has been sitting for a couple months, it wasn't running very well before it sat. Now it doesn't start anymore at all. Fuel filter is old so I decided to change it.
Upon removal of the filter, there was almost no fuel in the fuel filter housing. :confused:

I also noticed that there is a decently-sized puddle of diesel below the fuel tank, and it looks like there is a rubber hose leaking coming off the tank.

Based on the info that I got last night (http://www.thedieselpageforums.com/tdpforum/showthread.php?t=23839), I should be able to run the lift pump by having the transmission in D and turning the key to run? I can't hear the pump run when I do this at all, even when I stick my head under the truck.

Theory:
I have developed a leak between the tank and the fuel pump. While the truck sat, all the fuel leaked out of the line and I lost priming. This problem is made worse by the fact that my lift pump is broken or not getting power.

Questions:

Does my theory sound plausible?
Would a non-working lift pump cause the rough running that I experienced before the truck sat for a few months?
Does the fuel pump on the engine pull fuel from the tank even if the lift pump is not running?
Is there a way to re-prime the fuel lines manually in this situation?
How do I go about replacing the rubber hose near the tank?



Thanks in advance for all the help!:o

redbird2
08-02-2006, 20:31
First off I would look at the leak problem, not know where you are from here in IL we have had to replace the fuel line on 2 of our service trucks they rusted out at the tank and the truck where hard to start sucking air into the lines. to replace the lines you can drop the tank, or pull the bed off to get to the lines not possible if suburban.

now that you have the fuel line problem fixed check to see if you have power to the lift pump with key on if you have power also make sure the ground wire is good. if these are both ok them you will need to replace the lift pump

yes a defective lift pump can cause enigine to preform poorly if there was a pin hole in the line and you where sucking air into the system it will also cause engine to run poorly

yes the injection pump will draw fuel (not very well ) as long as the fuel system is not opened up or has any leaks
performance will not be like it should be

I have manualy primed fuel system before by applying air pressure to the tank with the bleed valve open on the top of the filter when fuel starts coming out the top of the filter shut the valve this will work

I DON'T RECOMMEND THIS MEATHOD CAN BE DANGERIOUS YOU CAN DO HARM TO THE TRUCK OR WORSE BLOW YOUSELF UP

fix the primer pump and be on safe side if you can not the primer to work search here for primer pump trouble shooting

good luck