5 ton running out of fuel?

[timntrucks]

got it started again today, new filter and some new lines, ran ok for a few minutes but it doesnt show much fuel pressure. after a bit died and i cant seam to get the pressure up with the manual pump. anyone know where to start? the filter didnt have but a very small amount of trash in it.it acts like it was sucking air from somewhere. is this a sight that the pump on the cummins is going out? it was used when i put it on

 

[poppop]

When I picked up my M813 it started and ran for about five minutes and died. Checked filters and they were fine but low on fuel. Took the line loose at injection pump and applied compressed air to the fuel tank to force fuel through. In the process heard a pop sound which turned out to be a dirt dauber nest in the vent line under the hood. With the vent stopped up the pump pulled a vaacum on the tank until it could not pump anymore and ran out of fuel. Long shot but worth checking before you pull the pump.

 

[timntrucks]

worth a try. are you directing me to the big inlet fuel line? mine could verywell be the same as yours, its got to be something small like that, i ran it for 3 months like it was on the old fuel filter, and i have plenty of fuel around 120 gals or so, and i filled the filter up with deisel before install. Tim

 

[poppop]

The tank on mine vents high on the firewall above the fording waterline. The fuel cap is nonventing to keep water out. The line should be mounted on the firewall somewhere. Put some air pressure in the tank and listen for air escaping somewhere.

 

[DDoyle]

I'll tell you two stories.

Had a deuce that would "run out" of fuel at about half a tank. The rubber hose that connected the electrice pump at the bottom of the tank to the discharge tube at the top of the paint had a hole in it. When the fuel level dropped below the hole, the gear pump in the IP could no longer pick up fuel - the hole time the electric pump really was doing nothing but circulating fuel.

Had a friend with a five ton gasser with a similar problem - the metal pickup tube had a hole in it, when the level dropped below that, he drew air, not fuel.

Haven't had the pleasure of owning a 8 or 900 series yet.

Regards,
David

 

[AMGeneral]

timtrucks,
Try this,disconnect the suction line from the outlet side of the fuel filter and drop it into a CLEAN bucket of fuel,then try and start it.If it starts and runs OK check for an air leak around your tank switching valve.If it still runs badly/stalls and your valve/injectors are set right then i'd look at the injection pump.


PS.I had my injection pump rebuilt 1 year ago for about $350-375,which included turning it up about 10%