M931A2 No Start

[tstone]

Just won up a M931A2 at Meade last week and went down on Friday to check it out and try to start it without success. Good batteries, tank selector on proper tank, solenoid working correctly, emergency manual shutdown in "normal" position and not interfering with solenoid, fuel in tank, drained slight bit of water from filter, trans in neutral, engine responds to a little starting fluid in intake, broke loose #1 and #6 injector tubes on IP, cranked and got no fuel from either one. Must be no fuel issue, maybe fuel selector switch or valve? Anyone else have an idea?

Thanks,
Tom

 

[jcappeljr]

I have got 2 trucks like that recently,Unhook the fuel line from the primer pump and stick in a gallon can of fuel.Pump the primer about 20 times or until it gets hard and you here fuel goig thru the lines.It should start.If so its fuel line issues.

 

[tstone]

John, thanks for the reply. This is the 1st 900 series truck that I have so I'm not familiar with it like the older ones. Where is the primer pump located? Is the IP the sole means of fuel delivery or is there a lifter pump in the system?

Thanks,
Tom

 

[M35A2-AZ]

The primer pump is on the side of the motor below the fuel filter. The ip bleeder is on the back side of the pump.

 

[tstone]

Thanks for the info! I'll try it out next week.

Tom

 

[wreckerman893]

If you are talking about the 8.3 Cummins I had a ell of a time getting the wrecker to start. I cracked two injector lines, pumped the crap out of the primer and it still wouldn't fire. To compound the issue I had to slave it since the batteries were low. I had replaced the fuel line that went from the hard line to the primer pump since they had plumbed in a small in-line filter that was suspect. When you prime it you should feel resistance when it primes and you should hear a "squish, squish" sound coming from the pump. You also have to make sure the electronic fuel shut off solenoid is in the right position. They have a tendency to de-energize and keep the fuel from flowing. Once you have it primed turn it over, if it starts retighten the injector lines (this is messy, fuel will be spraying out) once air quits bubbling out. Bleed all the injectors one at a time until all the air is out. If the fuel system was sucked dry you might have to prime the line by disconnecting the line that goes to the primer and using a small funnel pour in fuel until it goes all the way back to the tank. I had to do this to the wrecker also.

 

[wheelspinner]

WM that's way harder than it needs to be. Crack the vent screw on the back side of the front of the pump. Prime it until the air stops, tighten the screw and fire it off. Just did it yesterday.

 

[Suprman]

I believe it's an 8mm if you go too many turns it can fall out so be careful

 

[wreckerman893]

WM that's way harder than it needs to be. Crack the vent screw on the back side of the front of the pump. Prime it until the air stops, tighten the screw and fire it off. Just did it yesterday.

Thanks. I wasn't aware of that procedure. It should save me some grief from now on.

 

[M813rc]

It also helps if you fill the large fuel filter first.
Also, if you can lightly pressurize your fuel tank (either using rag around your air hose to "seal" the opening, or with a lid tapped for an air fitting), that helps a lot. By lightly, I mean around 5psi.

It is apparently a common enough problem, mostly with the tractors which have two tanks, that the Guard had a tapped lid in their toolbox, which they used to prime mine. I have since made my own.
My problem was an air leak in the fuel line by the tank switch tap.

Cheers

 

[Tinydragon2001]

Check your filter gaskets for any cracks or knicks. On my 925, there was a knick in the filter gasket, and an O-ring about a quarter inch in diameter that was missing from the bolt that runs from the filter mount into the housing. When I would prime the pump, fuel would come out the bleeder. I'd start the truck, it would barely idle. Hit the go pedal, and it would sputter and die. Checked the TM and the diagram show the missing O-ring. The motor pool had tightened the crap out of the bolt to try and get a seal without the O-ring. I bought a new filter, which came with the missing O-ring. Threw them in, truck ran like a top.

Thank God I had my buddy with me, who worked on these when he was in the service, because if it weren't for him, I would have been done.

 

[Tornadogt]

Link to how I get a truck started that had a dry tank...
http://www.steelsoldiers.com/showth...uot-Miss-Ava-Lynn-quot-Mods-and-Repairs/page4

 

[Suprman]

The 8mm screw on the top back of the pump is much easier. This is the military mechanics method that's where I learned it from. Make sure there is fuel in the tank. At least 5 gallons. Crack open the 8mm screw around 2 turns don't go too far it can fall out. Prime away till fuel comes out, sometimes you get a spurt of fuel and then more air you want to see steady fuel. You will probably have to push the primer 50 times or so. Once you have fuel tighten the screw and fire it up. I have done this numerous times and it has never failed. In theory you could crack the screw open and just crank it over the effect would be the same it's hard on the starter though.