M1008 starter headache

Hey guys, didn’t think this was gonna come down to asking here, but it has.

12v starter.

Drove the CUCV through some water halfway up 37” tires. Kept driving it that day, got home, parked it. Next morning, no start.

It would crank the starter and basically sound like it was grinding the teeth. I eventually came to the idea of replacing the starter thinking it wasn’t plundging properly or something.

New starter installed, go to connect batteries. Both positives on, go to connect first negative, and it begins to try to start the truck. This becomes problem number two.

Find out my positive wire might be connected to the R terminal that would be causing this. So I switched it to the other positive terminal. Go to connect batteries, again first negative attempts to start the truck, though this time the original teeth grinding sound is now a starter bench test type of sound.

So I have two issues here:

Why can’t I connect the batteries?
Why doesn’t the truck start?

Currently investigating the starter relay, which maybe I should have done first.

Thank you.

badtruck said:

Hey guys, didn’t think this was gonna come down to asking here, but it has.

12v starter.

Drove the CUCV through some water halfway up 37” tires. Kept driving it that day, got home, parked it. Next morning, no start.

It would crank the starter and basically sound like it was grinding the teeth. I eventually came to the idea of replacing the starter thinking it wasn’t plundging properly or something.

New starter installed, go to connect batteries. Both positives on, go to connect first negative, and it begins to try to start the truck. This becomes problem number two.

Find out my positive wire might be connected to the R terminal that would be causing this. So I switched it to the other positive terminal. Go to connect batteries, again first negative attempts to start the truck, though this time the original teeth grinding sound is now a starter bench test type of sound.

So I have two issues here:

Why can’t I connect the batteries?
Why doesn’t the truck start?

Currently investigating the starter relay, which maybe I should have done first.

Thank you.

Click to expand...

On a stock CUCV the starter is 24v has your been converted to 12V ? Probably be a good idea to post some pictures of your battery wiring.

It has been converted to 12v, yes.

badtruck said:

It has been converted to 12v, yes.

Click to expand...

This is about the only information on converting it , if it wasn't done with the Rosscommon conversion your probably on your own.

Rosscommon 24v to 12v conversion
http://www.steelsoldiers.com/showthr...12v-Conversion

porkysplace said:

Rosscommon 24v to 12v conversion
http://www.steelsoldiers.com/showthr...12v-Conversion

Click to expand...

But what did you link it for? The wiring is consistent with how it was before it wouldn’t start, the only thing I have touched is the starter and which R/S terminal to use.

But everything else within my 12v conversion is clean.

So what I’m saying is I don’t -yet- believe this has to do with the 12v conversion itself.

badtruck said:

So what I’m saying is I don’t -yet- believe this has to do with the 12v conversion itself.

Click to expand...

12v starter should have a large lug for the battery cable and small lugs one for engagfing the solenoid anf the other for accessory feed . It sounds like you have a bad relay that is sticking .

porkysplace said:

12v starter should have a large lug for the battery cable and small lugs one for engagfing the solenoid anf the other for accessory feed . It sounds like you have a bad relay that is sticking .

Click to expand...

That’s what I’m thinking now.

And for the starter, does the positive cable go on the larger lug or the other one that has the diode attached to it?