5 Ton Won't Crank Over

[sandcobra164]

Trying to recover an M818 today and failed miserably. I put good batt's in, hooked a slave vehicle to it, turned on the battery switch which provoked the air buzzer, went to start and nothing. I am getting a click from the protective control box and the voltage is dropping maybe 2 volts. Trying to jump the posts on the starter solenoid does cause the starter to spin but I can't hold onto it long enough to get it to engage the flywheel. Which direction do I need to be heading to figure this out? The voltage gauge is on the low side of the green and barely falls into the yellow when attempting to start. I checked the connections at the starter and they are tight. Help is appreciated, thanks!!!!

Joseph

 

[bigelk50]

Sounds like the plunger in the starter/solenoid is stuck. Have some one hold the run/start switch in the start position and try the screwdriver trick on the solenoid. If it does spin but not engage, the problem is in the starter. You could pull start it to get it going then repair it later if you are on a time crunch.

 

[bigelk50]

My truck gave me trouble. I freed it up then after a week fused the contacts together and melted the starter . $350 later all was fixed.

 

[goldneagle]

Trying to recover an M818 today and failed miserably. I put good batt's in, hooked a slave vehicle to it, turned on the battery switch which provoked the air buzzer, went to start and nothing. I am getting a click from the protective control box and the voltage is dropping maybe 2 volts. Trying to jump the posts on the starter solenoid does cause the starter to spin but I can't hold onto it long enough to get it to engage the flywheel. Which direction do I need to be heading to figure this out? The voltage gauge is on the low side of the green and barely falls into the yellow when attempting to start. I checked the connections at the starter and they are tight. Help is appreciated, thanks!!!!

Joseph

Did you replace all the batteries? If you have a battery with dead cells in it you will not get 24 volts to the starter. Were did you hook the slave vehicle to it? On the batteries or through the slave cable connection behind the passenger door?

 

[sandcobra164]

I replaced all the batt's with known good hawker agm's, I hooked the slave vehicle through the slave receptacle and it's tied directly into the battery wires. The only thing I get when turning the ignition switch to start is a thump from the protective control box, no thud from the starter.

 

[goldneagle]

Then it sounds like you have a starter or starter solenoid problem.

 

[ranchhopper]

Control box is bad mine did the same thing then I changed the box out it fired right up.

 

[GHall]

What did you end up figuring out?

 

[glj]

Control box is bad mine did the same thing then I changed the box out it fired right up.

I know this is an old thread, but by "control box" are you referring to the starter relay? The item in the fold down (M916) on the left of the glove box. You can jump start it here, but I think this relay on mine is bad. Thank you.

 

[doghead]

I know this is an old thread, but by "control box" are you referring to the starter relay? The item in the fold down (M916) on the left of the glove box. You can jump start it here, but I think this relay on mine is bad. Thank you.

He was referring to the PCB(protective control box) in an M939 series truck.

A M915 is not an M939 series truck. I don't know if they use one. The -20 level tm should have a troubleshooting section for "does not start", have you tried reading it?

 

[Floridianson]

Sounds stupid but does that truck have the lock out where you have to push in the clutch to start?

Also just might be me but it's called a screw driver because it's for screws not jumping starters. It's called a remote starter switch
and they are cheap.
OK now I just saw the date on this old thread. Owell it 7 in the morinig and too early is my excuse.

 

[glj]

Starter Relay

Sounds stupid but does that truck have the lock out where you have to push in the clutch to start?

Also just might be me but it's called a screw driver because it's for screws not jumping starters. It's called a remote starter switch
and they are cheap.
OK now I just saw the date on this old thread. Owell it 7 in the morinig and too early is my excuse.

Sorry, TM calls it a starter relay. Oops! Wrong thread.