M1009 Electrical Woes: starting issue

[Mike_Pop]

Ok...this is the third time that I've had problems with starting my M1009. Previous times, I was able to fix it but this time I am perplexed and just about ready to call it names like %$#@*&^^%%@$@$!!!!!.

Here's the scenario:
I had slow starting a couple days in a row, signs of weak batteries. Finally, on the third day it barely cranked over and then wouldn't crank at all. It wouldn't take a jump. The positive terminal on the front battery was corroded so I cleaned it up and it still wouldn't crank. I had the batteries checked and they weren't providing enough cranking power so I replaced both of them. Now I just get a click when I turn the key.

Ok...so I checked the starter. It turns out the solenoid had a problem. New solenoid and still just a click when I turn the key.

Next step: starter relay. I pulled it and jumped the red and purple wires. Still just a click. Checked all fuses (including ignition) and fusible links. Everything is ok.

I have 24 volts to the starter and the starter relay (red wires). I have 24 volts exiting the relay on the purple wire. I forgot to check the purple/white wire for voltage (that should be 12 volts with the key in the start position?)

Glow plug relay works just fine too.

How do I test the igntion? Does the rod on the steering column move much when the key is turned? How do I bypass the ignition to see if it is bad?

Everything seems to be fine but I am totally at a loss. It's really aggrevating.

Any suggestions?

Thanks in advance.

 

[Floridianson]

How bout the ground lead to engine block connection?

 

[beaubeau]

If you tried starting it with Low Batts. you have mare than likely Cooked the starter. From Day # 1, the all must have Good Batts. Between Glo plugs and Starter turning, there must be gooa AMPS. Even CIVY 6.2 have had this going on. Many times the starter will continue to Crank even when you release the key. Be sure to check all GRDS also.

 

[Crash_AF]

When you jumped the relay under the dash, you ruled out the column switch as being the problem.

Have you taken the starter off to have it tested? Did it test fine? It sounds like the bendix is hitting a tooth on the flywheel instead of meshing properly. The red and purple wires on the 28V relay under the dash are pretty much a straight shot from the batts to the starter, so I'm voting starter problem.

Later,
Joe

 

[Mike_Pop]

The starter was removed and tested and worked fine. It's not the starter.

Once again, I ask: how do you bypass the ignition to start it?

 

[doghead]

Here's the starting circuits schematic from the TM 9-2320-289-34. It also has some troubleshooting procedures in it. Have you measuered your battery cables for resistance(possible bad cable)?

 

[MarcM35A2]

Do you still use the original military block batteries? Car batteries might be to weak.
You said that it klicks if you turn the key. Right? Thats the relay of the starter. So the ignition works. I think it´s still a battery problem.
Greetings Marc

 

[Mike_Pop]

Brand new batteries, not car batteries, mil spec with higher cranking power. 12 volts coming out of the purple/white wire when the key is in the crank position. Battery cables are clean and look unbroken.

This is annoying because the truck has been sitting on one of my job sites for the past two weeks. I only have time to work on it after work and now I need it for next week. This is a basic fix but I simply can't find what is wrong. I've done all the obvious stuff.

By the way, it did occur to me to check the grounding strap from the block to the body but I'll be damned if I can find where it's located.

 

[CCATLETT1984]

I wonder if the wire going to the S terminal on the starter is bad. get a heavy screwdriver with an insulated handle, and short the large lug on the starter with the S terminal and see if it cranks.

The groud for the engine is on the passenger side rear, short cable that goes to the negative bus bar on the firewall. Speaking of, check the connections on both bus bars for gunk.

 

[doghead]

Battery cables are clean and look unbroken.

It won't take long to put your vom leads on each end of the cable to verify there is not a high resistance in one cable, causing your trouble. I've seen more than one cable that looked good on the outside but had high resistance and gave slow or no cranking.

Are you sure you have found and tested all the fusible links shown in the schematic above?

 

[Mike_Pop]

I wonder if the wire going to the S terminal on the starter is bad. get a heavy screwdriver with an insulated handle, and short the large lug on the starter with the S terminal and see if it cranks.

I had the starter off of the truck and brought it to a repair shop. It tested fine. The solenoid was not working properly so it was replaced.

 

[beaubeau]

I would still Check the S wire going to the starter. After what u went through, it could have Cooked it. Try Jumping with Screeewdriver on Starter. Good luck, Phil

 

[CCATLETT1984]

I wonder if the wire going to the S terminal on the starter is bad. get a heavy screwdriver with an insulated handle, and short the large lug on the starter with the S terminal and see if it cranks.

I had the starter off of the truck and brought it to a repair shop. It tested fine. The solenoid was not working properly so it was replaced.

What i'm suggesting is to take the wiring of the truck out of the equation. If it cranks when you short the two terminals you have good voltage getting to the starter, it would be the switched lead (S terminal wire) that would be your issue.

 

[dependable]

I recently put a gear reduction 24v starter # mt-28 in my 1028 work truck.. I bought from Nations Starter and Alternator. I have had the solenoids fail twice with no warning. The warrenty was honored. The propritor mentioned that the correct 24v Delco Remmy soleniod cost as much as the new starter he sold me( about $200). mabey we get what we pay for. In my experiance, the original non gear reduction starters work pretty well, but once they fail, the rebuilts don't last long. I now always keep a spare.

 

[Mike_Pop]

Thanks for all the help. I did locate the problem:

When I dropped off my starter, I had a lead wire off of the solenoid which makes installing the wires much easier. When I picked it up, the mechanic moved the lead wire to a different terminal on the solenoid. I always forget which terminal it goes on so after moving it to the S terminal, the truck started right up. Unfortunately, when I went to start the truck again, that lead wire melted. I'm hoping that it just shorted out somewhere. I'll replace it and see what happens next.

 

[CCATLETT1984]

I'm betting that its shorted out somewhere in the harness, glad you figured it out (kinda...).

 

[Mike_Pop]

I'm betting that its shorted out somewhere in the harness

The lead wire from the starter "S" terminal shorted on the exhaust manifold, melted the wire and fried the starter relay. An easy fix.

 

[beaubeau]

Mikepop, I have had a Head ache since I have been collecting MVs. Maybe it is time to get rid of some!!?? I can take anything mechanical, but when it comes to electrical, and Exhaust systems, I do not LIKE!!

 

[ARMYMAN30YearsPlus]

This is one reason we all love this site. I was working on a lieutenant's jeep the other day and noticed a few wires that had the insulation burned off due to being too close to the exhaust. Re-routed them and taped them up.

Really working on OD is easier than maintaining a relationship with a woman.....