A1 doesn't stay running.

Discussion topics on Willys Overland M series vehicles

Moderators: TomM, Moderator, wesk

Post Reply
User avatar
mdainsd
Member
Posts: 446
Joined: Thu Oct 19, 2017 6:00 pm

A1 doesn't stay running.

Post by mdainsd »

This is a new one for me. Helping a friend with his new A1 purchase. Nice original Jeep, no one has monkeyed with anything. Got it home and he cleaned out the tank, when through the carb and checked the initial timing. before we tried to start it we did a compression test as we had the plugs out to replace them anyway. 110 psi down the row.

Starts right up, sounds good and dies at 2 seconds in. It does this every time.

We fooled around with it a few times same result. Today we ran a jumper from the battery to the distributor just to rule out flaky wiring somewhere. Same thing.

Just for kicks i suggested disconnecting the two cables at the regulator. Guess what? Starts up, keeps running and sounds awesome. Ran out of time for the day.

While I have never come across this I will go into the generator and regulator with the meter next time. Seems whats happening (not yet verified) is what the engine comes up to speed the generator cuts in and apparently that is shorting the system. Of course as soon as the engine stops the fault clears and you can start it up right away and it dies again. My "guess" and that is all it is at this point is that the armature is shorted to ground in the generator or the connecting cable. Regulator cuts in hooking the armature to the system which kills the system. We will see...

Interesting problem, wondering if any of you have ever run into this one. We have spare generators and regulators so it won't be a problem getting the Jeep running. I just want to dig further and pin point the failure mode.
'52 Dodge M37, '42 GPW, '48 FrankenJeep CJ2A/M38, '50 CJV-35(U), '51 M38, '42 WC-57 Command Car, '44 WC-51 Weapons , (2) M1941 Sperry 60" Anti-Aircraft Searchlights, John Deere M-gator, '44 White M3A1 Scout Car
User avatar
OKCM38CDN
Member
Posts: 530
Joined: Thu Feb 16, 2012 6:00 pm
Location: Del City, OK

Post by OKCM38CDN »

Assuming it has a mechanical regulator. I had a similar thing, check the breaker relay in the regulator. It may have tripped and preventing power from getting to the system...

If it did would clean the contacts and go from there...

Not saying that is the problem but something to look at...
Hal, KB1ZQ
TSGT, USAF (Ret)
1952 M-38 CDN CAR 52-31313
1952 M-100 Strick #104
1951 Willys Wagon (For Sale)
1954 Willys M38A1 201001205
Tornado Alley
Del City, OK
User avatar
mdainsd
Member
Posts: 446
Joined: Thu Oct 19, 2017 6:00 pm

Post by mdainsd »

Yes. one of several things to check. I have had these generator/ regulator combos turn into "motors" that tried to turn the engine when you shut the vehicle off.

Still has a mechanical regulator. Just picked up another generator, regulator and cables at Plymouth a few weeks ago. 35 bucks for the whole shebang.
'52 Dodge M37, '42 GPW, '48 FrankenJeep CJ2A/M38, '50 CJV-35(U), '51 M38, '42 WC-57 Command Car, '44 WC-51 Weapons , (2) M1941 Sperry 60" Anti-Aircraft Searchlights, John Deere M-gator, '44 White M3A1 Scout Car
Post Reply