Cranky Jeep

[FrankenJeep]

Ah well, you learn something everyday! My jeep was unreliable, hard to start, would "strand" me. I was afraid to take it out. So I laid off for awhile (tell ya the truth, I was "mad" at it so went dormant for awhile.

Got it back out after looking and looking and looking to find why it would quit without warning. Replaced every part I could imagine! Still die. Made me break my toe (OUCH! no, not that way, but a long story) Quit the last two Fridays and had to be hauled back on a rollback.

I "think* I found it. When it quit Friday afternoon, I got a friend to come over and help me--mainly by cranking it while I watched to see what was going on in the distributor. I was about 80% sure it was in there. No FIRE! AT all!
WHUT?????? Further examination showed not only no fire, but the points weren't moving!!!!!!! ????????????? Well, no wonder there's no fire! Discovered that they had moved so that the little "cam lobe" contactor was not touching the dist. shaft! I readjusted them so they touched the shaft, set the gap (was no need) and cranked it over. RRR_VROOOM!!!
Humming like a Singer sewing machine! No "skip", no throttle hesitation, nothing but the hum of a Jeep!!! I let it sit and fast idle for almost an hour with no issues. Cranks like it should!

So a lesson learned. It "fooled" me at first because when I twiddled the points with a screwdriver, it would spark. But that tiny little gap where the little lobe wasn't touching wasn't evident because I couldn't be out there to see that they weren't being activated. Only when I had someone to help me could I see the problem. Next time this thing quits, this is something else on the list to check. *Somebody* didn't tighten down the points when he installed them and allowed them to gradually slip out of place. That explains the funky running!

Hope it lasts!

[QCIM38A1]

I had a similar situation with my old M37, which uses a similar distributor. The truck just started spluttering, lost all power, and died in the middle of crossing a trench. No spark at the plugs, so I opened the distributor and found the rubbing block on the points had cracked off. Not opening at all.

Another time it gave me no end of grief, it would start fine, then immediately start running like a bucket of bolts. I was getting very annoyed, but I happened to notice a metallic "tink" coming from the distributor. I took it all apart, and found that one of the springs for the centrifugal advance had broken, and as soon as it was running, the weights went all the way out. The "tink" was the spring hitting the inside of the housing.

[wesk]

Actually whenever you troubleshoot erratic ignition always check for loose parts. You don't need someone to crank it for you. Just open the hood, pull the distributor cap, push on the generator belts while turning the fan in it's normal direction and watch the points. You can set the rubbing block on the high point of the cam by rotating the engine by hand using the fan with a little hand pressure on the belts. Then once on the high point of the distributor cam you can grab the rotor and turn it several degrees against the centrifugal advance springs and let it pop back while watching the point motion.

[QCIM38A1]

Also, always check for spark at the plug wires, even if you have spark at the points. You can do this without a helper on the M38A1 or M37, just hold the plug wire about 1/8" or so from the block, with your right hand, while pulling the lever on the starter with your left hand. Of course, on the M37, your hands are reversed.... Anyway, always a good idea. Be careful that you don't shock yourself! It really wakes you up!