Help starting M936A2 Wrecker

[SouthJL]

FIXED - Help starting M936A2 Wrecker

Hello All,

If anyone can give me some real quick advice, the driver is here with the truck on the trailer and it won't start.

According to the report it started with a jump, so I have two new group 31 batteries hooked up to it. Connected them together with one of the short cables from the truck. Then With 4 gauge jumper cables from + to + and - to -. Do I need to take the jump cables out of the equation and take out the old military batteries.

I thought I was prepared, but finding out I'm not.

It will turn over, but not run. I've only attempted to start about 6 time with time between each attempt.

I'm reading through the manual... again, but I was hoping to learn a lot of this stuff on the ground.

 

[SouthJL]

And... if it comes to it. What kind of garage/mechange/wrecker shop should I be looking for?

 

[86m1028]

Check your Elec fuel shut off

Bypass the truck batts & see if it cranks easier

My a2 fires off almost instantly even after sitting for months.

 

[porkysplace]

[h=1]fuel shutoff solenoid on the cummins 8.3[/h]

 

[Suprman]

Im thinking it lost prime. If you stand on the drivers side tire looking over the injector pump, on the front back there is a small bolt. 9 or 10 mm if I remember. Loosen 2 turns no more it can fall out. Drivers side of the engine is the primer on the lift pump. Pump 100 times or till fuel is coming out the bolt. Tighten bolt and start. Make sure the fuel solenoid is moving also. They dont like low voltage. You can move it by hand and once the truck starts usually it will stay engaged.
Will

 

[SouthJL]

Thank you again for the suggestions. Got it off the trailer... driver was awesome to work with. I think it was combination of two things... my inexperience and trying to use jumper cables.

I thought the 4 gauge cables would be enough, but until I took two of the old military batteries out of the compartment and put the two new batteries directly to the battery cables, it would appear that two batteries just didn't have enough to start it.

Only other thing I might have done was to give it a little bit more fuel when starting. If I read the TM right, I wasn't supposed to press the accelerator until after it started for the -A2 model. But I'm confused on the note.

WP 0006 says...

NOTE • Perform Steps (10) and (11) for M939A1 vehicles. • For M939A2 vehicle, crank engine first, then depress accelerator pedal all the way down. When engine fires, release pedal to partial travel.

10. Depress accelerator pedal (Figure 1, Item 5).

Do not operate starter continuously for more than 10 seconds at a time, or with headlights on. Wait 10 to 15 seconds between periods of starter operation.

11. Place ignition switch (Figure 2, Item 3) in START position. Release switch (Figure 2, Item 3) after engine starts.

Are there two distinct attempts to start the engine on an -A2? Or is this just a brief delay before pressing the accelerator?


Now that I have calmed down, I'm not sure if also keeping the 4 bad batteries in the power circuit was part of the problem too.

 

[Jbulach]

Congratulations!!!

Yes bad/dead batteries will make for a much more difficult jump.

Just as long as it's not cold outside my A2 fires off in a fraction of a second with no pedal. Also spins over extremely fast with good batteries.


M925A2 with dump hoist

 

[dmetalmiki]

You just can not beat GOOD batteries. Congratulations on your acquisition, and now is the time ( as your pulse returns to normal!) to post up some pictures of the truck.

 

[SouthJL]

You just can not beat GOOD batteries. Congratulations on your acquisition, and now is the time ( as your pulse returns to normal!) to post up some pictures of the truck.

Once again, thank you all! Pictures are on a new thread.