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On Saturday I attempted to turn the M37 around, prepping for the rear brake adjustments. No go: hit the starter which cranked good for a couple of seconds, then nothing-no juice to the starter, gauges, lights, diddly. Didn't have time to troubleshoot but I suspect I blew the main fuse somehow (some might recall that I run a Painless Performance harness, complete with a big 70amp main fuse mounted on my firewall). I also run the military battery isolator switch but don't believe that is the problem. Anyway, I'll get to check it out this afternoon. Bummer too-we got a couple of inches of snow with more on the way, and I'd like to get a couple of snow shots of the M so I can post 'em here.
More to follow,
Gary

You have a fuse in line with your starter ?

Sal

Thanks Sal,
No, everything runs off the fuse block. I got to troubleshoot this for a bit, this afternoon with my multimeter. Good battery charge, no problem with the isolator switch, got power at the postive starter post, but nothing at the ignition switch, gauges, electric fuel pump, or the lights. So, I pulled and ran continuity checks on all the fuses and all are ok. The only thing left to check is what appears to be a big relay that is on the bottom of the fuse block-I didn't want to break it, having never removed it, so I dug up my Painless Installation manual and am going to review it in a day or two. I can't think of anything else that would cause this, so I think I'm close to identifying the culprit.
More to follow,
Gary

Gary,
Hope you find your gremlin soon. "Painless" wiring harness? I never heard of that brand, is that like a stock car/ street rod type wiring set up?

Gary. I would think about using a 24 volt test lamp instead of the multi meter. Sometimes a meter can turned you around. Just my $0.02..

Sal

Thanks guys,
David, Painless Performance is the industry leader in wiring harnesses, for everything from light cars and trucks, race cars, up through industrial applications. I installed their Non-GM truck harness on my M37 and it's worked flawlessly for the past 4 years.

Sal, I emailed Painless last night and await their response (another nice thing with Painless-their customer support staff is also great)!
Gary

Well it wasn't a fuse after all. I suspected my engine to frame ground strap might be loose or rusted up so I removed it and cleaned the terminal ends and mount points then reinstalled it--still a no go, so I started back at square one, pulling the battery cable terminal clamps in order to clean them up and apply some dielectric grease. I did the negative cables first which was uneventful, but when I proceeded to the positive side the positive post clamp fell off the end of the cable! POS I thought, so I ran up to Auto Zone and got a new cable with terminal post clamp.

I did not have time to install it this evening but should have time tomorrow afternoon-hopefully that solves my problem. I can only figure that I still had 12V at the starter lug because the cable end was just touching enough to send a 12V signal to my multimeter, but not enough to fire anything else.
Stay tuned,
Gary

Gary,

Sounds like some positive progress. Keep us posted.

Bert

Thanks Bert,
OK-sure enough, it was the positive battery cable. I made time to install the new cable today and am now off the deadline list, up and running. Now I can resume work on adjusting the rear brakes, having finished the front before the battery cable extravaganza....
Gary

Gary,
I checked out their webpage. Neat stuff. Glad you found your cable issue. Electrical can be such a pain sometimes.

Good work Gary...

Sal

Gary,

You forgot to post pictures of the cable repair. Glad to hear that you found the problem quickly.

Bert

Thanks guys! 10-4 on the pix-later today perhaps-snow is also coming in this weekend so I'll see about taking some snow shots as well!
Electrical scares the heck out of some people but since I wired the whole truck with that Painless kit I knew I'd be able to run it down. I will confess that I didn't wire in the military headlight switch-ran out of time to isolate the wiring pattern so I used Painless' switch....
Gary

Junk cable....