I took in a truck to work on last week & just wanted some opinions on my findings & diagnosis.

the truck is a 94' auto w/ well over 400k miles, all I knew was that it wouldn't start, first place I looked was the fuel shutoff solenoid, it worked fine, so then drained a little fuel from the filter to make sure I had fuel to there, sure enough had fuel, next I cracked a line coming from the DV's & pumped the hand pump to try & get fuel to the lines & nothing, cranked the truck & kept trying to prime it , but never got any fuel to the lines, I decided to get a new filter & start fresh the next evening. next day took the filter off & pumped the primer on the lift pump & couldn't get any fuel up to the filter base at all, so I pulled the bowl off the bottom of the fuel heater to check the screen inside, this thing was full of either a sandy or sugary substance??? it was packed full of this junk, so I cleaned all the crap out of it that I could & replaced it, but still no fuel, by this time If I used the primer it was squirting fuel out from around the primer itself, last resort I put everything back & pressurized the tank with an airhose, I got fuel to the bowl & filter, then tried cracking the supply line to the injector pump & cranked the motor over, but the lift pump never sent any fuel through the supply line, so today I went & picked up a new lift pump & I guess I'll pull the heater/bowl/ screen & everything apart & clean it then try it with a new lift pump, any thoughts??


& for the record I realize that the entire fuel system needs to be cleaned of this sandy stuff, but the owner just wants it running enough to get it to a local cummins shop where he's from or something???? so should this get the old goat back to limping down the road again???

 

Perhaps the filter in the tank is clogged up also. Pushing the fuel though with air may get results where sucking with the pump doesn't just because it's stronger. A P pump will suck fuel and the the engine will run even without a lift pump as long as there is no air in the system. If you pressuize the system from the tank with the inlet banjo on the injection pump open all air can be removed.

If you don't want to drop the tank or lift the bed maybe blowing some air backwards though the system will unblock it enough to get it where the owner wants. Be sure to open the fuel fill cap and stick a long screwdriver down the tube to keep the roll over ball from blocking airflow.