No fuel suction

[5tonman1971]

Ok so I've been trying to figure this out and I'm finally throwing up the white flag and asking for help.

My 925a2 was running fine it sat for 3-4 weeks and lost it's prime I've replaced all the rubber fuel lines already.

so I tried to prime it back up over the weekend and boom it fired right up for about a minute then shut down, no fuel at IP. I cracked the petcock on the primary fuel filter, it started to suck air in and was under a vaccum. I can disconnect the fuel line coming from the primary filter to the hand pump and put it in a 5 gallon can and it will run from that.

This is leads me to believe I have a restriction In between the primary fuel filter and fuel tank. Has anyone had this issue and corrected it properly? I'm assuming that my pick up tube has collapsed or is clogged but like I said before the truck was running fine the last time I shut it down. It had about an 8th of a tank so I put 10 gallons In to see if it was just empty but to no avail.

can anyone point me in the direction on where to check for a restriction? I've thought about blowing the intake line out towards the tank but then all the crude will just go back in the tank if that's the issue.

is there any way to pull out the pick up tube?

 

[wreckerman893]

Did you make sure the fuel shut off solenoid is resetting? If it de-energizes the truck will not start. There is also a bleeder screw in the back side of the injector pump. Loosen it and let "soldier B" crank the truck. It should start if fuel is getting to the IP.

 

[162tcat]

Did you try it with the fuel cap off? The vent line could be plugged.

 

[doghead]

Fuel pickup tubes in the tank are known to pinhole(rust) and cause a loss of prime.

 

[5tonman1971]

Yes the fuel solenoid is energizing, stret of fact it's working so well it burnt the heck out of my arm while I was trying to remove the fuel line from the hand primer.

Yes i I did try with the the fuel cap open.

After er every time it dies I check my air bleeder on top of my primary fuel filter and I get a sucking sound as it's releasing the vaccum from there being a restriction coming from the tank.

 

[Csm Davis]

You said you replaced all the fuel lines, with what type of hose? The military uses the high pressure fuel injection type hose that has wire in it to keep it from collapsing under suction.

 

[73m819]

No fuel suction? Maybe you are NOT paying enough.

 

[R Racing]

Did you try the opposite? Take your line loose before the pump and pressurize the tank to see if you can push fuel thru the system ? I have had to do this on my 813 when I had issues.

 

[5tonman1971]

You said you replaced all the fuel lines, with what type of hose? The military uses the high pressure fuel injection type hose that has wire in it to keep it from collapsing under suction.

I had the local hose company replace all the rubber hoses with the correct rubber hoses that where removed the only thing that was not replaced was the hard line coming from the tank.

 

[5tonman1971]

Did you try the opposite? Take your line loose before the pump and pressurize the tank to see if you can push fuel thru the system ? I have had to do this on my 813 when I had issues.

No no I did not try that. It has 3 vents I would have to plug to do that anyway, and I do not have an extra fuel cap to put a shradder valve in to be able to pressurize the tank. Maybe I could use one of the vent lines though.

 

[5tonman1971]

No fuel suction? Maybe you are NOT paying enough.

Yea maybe that's what it is.....

 

[162tcat]

You can get enough pressure in the tank just using a blow nozzle and rag. It's safer that way too since you don't have to worry about over pressurizing it as much.

 

[pctrans]

Disconnect the fuel supply line at the filter, and the fitting at the top of the suction tube. Use a blow nozzle and blow into the filter end. You will then be able to see if you had an algae buildup in the supply line. Then blow down into the tank to see if you hear bubbles. No one else asked, but......you DID check to see of there was fuel in the tank???

 

[M35A2-AZ]

Here is a post about the problem I had with my M923A1 fuel tank.
http://www.steelsoldiers.com/showthread.php?79327-M923A1-losing-prime&highlight=fuel

 

[5tonman1971]

Disconnect the fuel supply line at the filter, and the fitting at the top of the suction tube. Use a blow nozzle and blow into the filter end. You will then be able to see if you had an algae buildup in the supply line. Then blow down into the tank to see if you hear bubbles. No one else asked, but......you DID check to see of there was fuel in the tank???

yes in the OP I said it had an 1/8 of a tank and I put another 10 gallons in so I think I'm good on the fuel level.