M1028 will not start

[bigredlab]

My 1985 M1028 will not start and im not quite sure why. its been haveing trouble for a few weeks, but today it would not start at all.

The wait light comes on and stays on for a long time (nearly 30 seconds). I hear the solenoid click.

So far, I've replaced the air, oil, fuel filters, and batteries. Yesterday after replacing the batteries, the truck started right up.

This morning though it would not start, so I went ahead and replaced the glow plugs because I thought that might be a problem (because of the long wait light). I also cleaned the control card with an eraser.

I've checked the voltage on the batteries and the voltage at the glow plugs. Both are good.

I tried taking the truck out of park and putting it back in park. No joy. Tried in Neutral, no joy.

does anyone know what could be wrong?

what I am missing?

 

[ODdave]

Is it a crank no start or no crank no start?

 

[bigredlab]

this morning it was crank to no start, now its no crank no start

 

[GM72K10]

Things to check: Fusible links, Neutral safety switch, starter relay, fuses. Isolate one possible problem and move on to the next one. good Luck.

 

[idM1028]

You may also want to check the alts. I've been told that a bad diode in the alts can drain the batteries even while the truck is sitting with the key off.

 

[mistaken1]

There is a great troubleshooting section in the TM.

http://www.steelsoldiers.com/cucv/67999-download-cucv-tms-here-where-download-cucv-tms.html

 

[bigredlab]

OK,

I have now gone through the troubleshooting steps in the -20.

I replaced the starter. When I went to start it, all it did was click (just like the old one). The old starter was bad, but turned over on the tester (all it did was click in the truck).

I checked all of the connections that I could find, still no luck.

Checked the Batteries (brand new) again with a load tester. No luck.


Plan now is to pull the starter again, and see if it will turn over without being mounted. If it doesn't, I will take it to have it tested.

I am at a loss as what to do next or where else to check.

 

[bigredlab]

Any help? Please?

 

[bigredlab]

The starter would not start unmounted but would turn on the tester. I also checked the glow plugs again and found out that I am only getting about 30 milivolts to the glow plugs and they are not heating up. could really use some help

 

[davidkroberts]

man i dont know you need to pm doghead, he is kinda the resident expert on CUCV electrical issues. this is a strange one. Have you got a copy of the wiring diagram

 

[Matt65]

Are the engine grounds in good condition?

 

[GM72K10]

Do you have a voltmeter? Go through the TMs, there are wiring diagrams for EVERYTHING, check for voltage where its supposed to be, I've had about 20 of these (only 2 of them were bought running) and only 1 of them I couldn't get to start (had an ip from a HMMV, was never going to start cause its 24 volt) Patience and read up on the wiring, clean all connections including grounds, bound to be something you haven't checked yet.
Good Luck.

 

[ryan77]

Did you check the relay under the dash! Do the doghead conversion!

 

[M1008driver]

Check the pink and green wire for a good connection. I bumped mine once taking of my air breather and my truck would not start. Glow plug solenoid? Orielly's told me it was a starter solenoid, but doghead set me straight. I was just confused. CUCV Electric has new gp relay cards for a good price.

(I say all this because you said the gp light stays on longer)

Keep an watch on your batteries if you are cranking allot. Clean and check your connections.

Most of all use your voltmeter and download the TM's to troubleshoot. Trust me on this...

EDIT- I keep reading neutral safety switch, but my 1985 M1008 will run without the switch connected and my old switch was better than my new "made in China" switch" with cheap plastic that broke. The switch also runs the backup lights, but like I said, my engine will crank without it so I don't consider the switch critical. (note-I do have the switch installed for all you safety guys)

doghead mod is a must, but that is for the starter.

 

[citizensoldier]

It sounds to me like you were getting air in the system and your glow plugs were not working right and then you might have fried the starter relay trying to start it. shinny thing under the dash.
I would do the doghead glow plug upgrade because it also sounds like your glow plug card is not working right. Cycling to long. This way you bypass it and get good juice and popper glow plug ignition for a cold start.
Once you get the starter turning right and you know your plugs are firing and it wont start I would then examine to make sure your getting fuel through the system. You might have a toasted IP, or sucking air through the filter housing.
Crack all the injector lines and have a buddy turn it over. As fuel starts to pump out each injector stop and tighten them. If you know you have fuel and plugs and still no start then crab a 44 mag and put one in its head.