Lmtv starter

[jimbo66348]

I tried to start an lmtv today with two charged batteries. The ground was connect to one - post the hot was connected to the + terminal on the other battery and the other two were connected together. The 12v lead was connected to the positive terminal on the grounded battery. When I hit the starter button, the starter would just engage and immediately release. If I held it down, it would just bump and bump and bump. Any ideas?

 

[NDT]

Maybe the thermal switch going out on the starter. Jump it out and see if that fixes it. Could be a dozen other less likely things.

 

[jimbo66348]

Maybe the thermal switch going out on the starter. Jump it out and see if that fixes it. Could be a dozen other less likely things.

Well, that's one I've never heard of. Ive never seen anything like this happen before, so I was hoping on an lmtv particular issue. Maybe i can check. It's in a field with flat tires. The cab doesn't tilt and I can't get under it.

 

[jimbo66348]

Thank you for the info.

 

[doghead]

Wet? Frozen?

 

[Suprman]

Low voltage use 4 good fully charged batteries

 

[jimbo66348]

Low voltage use 4 good fully charged batteries

Not wet or frozen, and two charged batteries are more then enough to turn over these tiny engines.

 

[Suprman]

The starter has its own battery lead going to 24v at the batts. On the solenoid the terminal closest to the block is the positive. Use a clip lead and try to crank touching the solenoid positive to the main positive on the starter. Old worn starters sometimes need a little extra power to crank. If the solenoid fully engages and the starter wont spin sometimes the terminals at the end of the solenoid are burnt and pitted. I would still try 4 fully charged batts if it wont go.

 

[Feal318000]

Occasionally when I go out to start mine- ill push the button and the starter will engage for a split second, and if I continue to hold the button, a split second later it will crank normally and fire right up. The starter itself appears to have been replaced very recently.... maybe a electronical ghost somewhere. It hasn't bothered me enough to diagnose it any further, considering it only does that about 1 out of 15 or so starts. Obviously there is something wrong, but it hasn't seemed to get any worse at all- or leave me stranded yet.

 

[Suprman]

The neutral safety and other crank lockout relays are in the vim module behind the passenger kick. There is an aux start relay on the frame rail near the starter also. Its always best to start at the starter itself and work your way back.

 

[jimbo66348]

Low voltage use 4 good fully charged batteries

Not wet, frozen, or low voltage. Two batteries are more than enough to spin that tiny motor, especially at 24 volts.

 

[gavland]

I have the same problem with my 97 M1088, when I first got it it would do the starter on off every soften. now that's all it does tried jumping the relays and did the same thing.
out of 100 times I tried to start it got it going 1 time, left it run for 1 hour shut it off and tried to start it rite away and on off went the starter again.
when the starter stops all the gauges and buzzer stop for a second then on goes every thing again over and over and over till I let off the start button........like having a lose wire somewhere but cant find any.
what does the round box on the frame beside the starter do??? it has a ton of silicone on the back side covering all the wires. tried pulling on them to see if it would help but nope!!

 

[Suprman]

Sounds like your batts are weak. You could try cleaning all the batt connections. The relay on the frame is aux start relay. Jumping the 2 big terminals will crank the truck.

 

[gavland]

4 new batteries and I even was thinking that so I had my M925 jumping it too to add extra power, no change!!
to cold out there today to mess with it more.

 

[Suprman]

Replace the starter

 

[FSRD]

I have a 97 m1078 that has starter issues. The problem I have is when I push the starter button all I hear is a small click and the starter does absolutely nothing. I can jump the starter and it will fire right up. The clicking sound is the sound that you would hear from a relay clicking on and off but that's the only sound it makes when I try to start it. Any ideas on what it could be? Thanks!

 

[coachgeo]

are you jumping starter with the trucks own batteries or with a different 24v power source?

 

[Suprman]

Could be the start relay in the panel. Vim could be preventing crank it had all the neutral protection in it. Aux start relay on the frame rail.

 

[FSRD]

I am jumping the starter with the trucks own battery. It will start up and stay running every time I do that.

 

[Suprman]

The tm has simple troubleshooting for that. All you need is a multimeter.