M38 mating to a CJ2A motor

1950 - 1968, M38, M38A1, M170, modifications, sugestions, and ideas, official MWO's and unofficial field mods.
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Rhino4305
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M38 mating to a CJ2A motor

Post by Rhino4305 » Wed Aug 16, 2023 9:18 am

I purchased a 51 M38, the 24 volt system was stripped. I inherited a CJ 2A motor with the standard 6v starter and generator. Can I mate the CJ motor with the 6v MZ starter to the M38 “early” bell housing? Will the CJ 2 engine plate work? You probably noticed that I’m a novice….


Ron D
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Re: M38 mating to a CJ2A motor

Post by Ron D » Wed Aug 16, 2023 4:28 pm

More than a few potential issues. None insurmountable.
Is the CJ engine gear drive or chain drive?

The engine mount ears on the motor front plates for M38 and CJ2A motors point different directions (CJ both point rear, M38 one front one rear).
Probably no issue with the bell housing if flywheel tooth count and starter bendix gears mate.

You might want to study this old post (and search others) about the different front engine mounting plates and other issues like voltage, fuel pumps, distributors, and the differences between chain and gear driven L134 motors, etc:
viewtopic.php?t=319240

Lots of good M38 information over on the willysmjeeps forum.
Like this post: http://www.willysmjeeps.com/v2/modules. ... highlight=
And especially free download of the technical manuals for what you're doing.

Good luck!
Ron D
1951 M38
1951 M100

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dpcd67
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Re: M38 mating to a CJ2A motor

Post by dpcd67 » Fri Aug 18, 2023 7:51 am

Odds are that your CJ2a motor is gear drive, in which case the only thing you need to be concerned with is the type of bell housing, ring gears and starter. I have changed all that to the late BH, 129 tooth gear, and use a Land Cruiser starter; it always works.
You want to pull your flywheel and have it ground anyway. Put a 12 volt alternator on it since you aren't going back to original anyway. Come over and I'll show you a couple like that. One on the engine stand as we speak. Write. Type.
Get the green M38 restoration book too. Even if you aren't actually totally restoring it.
Oh, first post I see; welcome to the forum.
Now get a full set of TMs and the Jeep Universal manual and study them. Every day. I do.
U. S. Army 28 years.
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