Help Needed desperately

[bigbee]

This could be an M37 question or general electircal-but I'm perplexed.

Bought M37, started and ran fine, except the only electrical that worked was gauges, turn signals (12V), and horn. Rest of wiring was shot, one headlight was black.

Bought new harness (second hand, never installed before) and installed same. Once I got the dash wired in, my buddy says see if it starts. It started and ran well.

Headlights were hooked up and tried, they faded out after a few seconds of bright light. I did have to cobble the headlight to harness pigtails, didn't come with the set. Marker lights and taillights (new replacement composite lights) installed after the headlights seem to work fine. .And headlights are still melting, not going dark like burning out but smoking and turning bright white inside.

Truck started 3-4 times, ran strong, til the last time it suddenly ran rough and died. Now it doesn't seem to get spark, though I checked the coil against ground and had 24v to the points as far as I can tell. I do have extra parts, and have replaced all of the pieces in the distributor, set the points according to specs, etc. Have not replaced the plugs (I have extra new ones) nor the plug wires (I do not have these). Starter is cranking good, ignition switch is working.

Are these problems related?
Is it a grounding thing?
Do I have to redo the whole wiring loom or just part?

I'm not a real mechanic, and I don't have a lot of test equipment-just a small multi-meter.
Simple, easy steps, please.

 

[mangus580]

Sounds to me... like your truck was setup 12v before? (at some point or another?) I suspect you have fried the coil.

 

[bigbee]

fried coil

Among the rat's nest of wires he had under the dash were a couple resistors that ran the heater motor and the turn signals, I believe. Otherwise it was still running on 24v. I can replace it again, just to check. I've got 3 or 4. Anyway to check the coil for sure before putting it in?

 

[ARMYMAN30YearsPlus]

RE: fried coil

I had a dodge dart with a 170 Slant six that stopped dead it had me foxed for a few hours till I checked there ground inside the distributor and it was not good. Fixed that with a new screw and some WD 40 and it ran for the rest of the time I drove it

 

[derby]

RE: fried coil

What about the voltage regulator? I am not familiar with the M37, but in any over charge situation a lot of stuff can get fryed! was the first harness all melted together?I had a VW sand rail with a bad volt reg. blew out 4 brand new halogen flood lamps,tail lights,marker lights and instrument panel.and yes the flood lamps had the white smoke inside and also started to melt the glass! Were the points burnt? check continuity on the coil ,you should get resistance on all terminals including center post. when you get it running see what kind of volts the generator it is putting out.you can remove the cover on most regulators and check to see if the contact points are rusted or corroded or just plain stuck. hope this gives you some help

 

[bigbee]

RE: fried coil

Derby-No, the original harness wasn't fried that I noticed. It was just frayed and bare in several places. The 3-lever switch didn't work, which was apparently the only thing that kept the truck from catching fire. I'll check into the voltage regulator to see if it's the culprit. The points in the distributor when it quit running were not damaged that I could tell.

David-I'll go back through the distributor and check for that ground and double check all the connections, again.

Thanks for the input.