Starting problems on M923A2

[zguinness]

I've been having some issues with starting my 5 ton lately. I'll try to explain as best I can.

- If the truck has been sitting for a while (several hours or more) it will start right up.
- If I shut her down and try to restart anytime within the next few hours it takes several attempts before she will start up.
- If I shut her down and try to restart within a few minutes to an hour or so she won't start at all.

It's like the longer I let it sit between runs, the more likely it is to start up. This morning I needed to jump another truck and my truck had only been shut down for about 45 minutes. I couldn't get her to start using the switch so I had to cross jump the starter (I guess that's the right terminology? Took a wrench and jumpered the solenoid).

Bad solenoid?

I just don't get the time thing... like how she starts fine if she's sitting for a while.

 

[juanprado]

It sounds like your starter itself is bad. The brushes are worn or windings could be bad and with heat expand and lock up. With time, they cool and back to normal. With automotive starters you can sometimes cheat by lightly taping the body of the starter and the towards the back where the brushes are located to free them up. Solenoid could also be hanging up.

You can check with a meter the amps it is drawing at starting or a parts store could bench test it. I suspect the draw is off the chart when hot and that is why it does nothing.

The solenoid is available separately but I always recommended changing the starter complete with a solenoid.

 

[timntrucks]

i have seen that problem before. if is not the starter and it well could be that its the black box on the firewall. what its doing is one of the relays is kinda stuck so it thinks your truck is running and will not let it start up. after several hours the relay goes back to normal. its sensing the oil pressure and if its stuck with some pressure in that relay it thinks the engine is running with built up oil pressure and will not let it restart. i hope i made some sense. same thing happened to my 816

 

[NJDEUCE]

I had the exact same problem with my truck. You need to reset your fuel shutoff linkage. Your emergency cutoff switch was most likely pulled. It's a simple fix.