Matching the bell housing to engine?

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strathdaigeil
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Matching the bell housing to engine?

Post by strathdaigeil »

I recently discovered that my CJ3a has a terribly cracked block (641087 style )
which spans half the width of the engine and causes oil and coolant to mix and then spew out a stripped exhaust manifold bolt. So in addition to the other problems, I get a nice smoke up from the engine and from the exhaust when I run it.

I have made arrangements to acquire an L134 engine from a former motor pool sergant who has newly rebuilt an 804380 - late m38 style block engine and he tells me that it is for the sealed/waterproof bell housing. My question is, if my current bellhousing is not the "waterproof" version, will I need to look for and purchase one that is or will it bolt on safely and securely but not be completely waterproof?

Is there a model/casting number I can look for on the bell housing?
Thank you.
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4x4M38
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Post by 4x4M38 »

See Wes' photos here of the four L head blocks and the differences.

http://www.willysmjeeps.com/v2/modules. ... _album.php

If he has the ten bolt bell housing mount and the two 1/2" starter
holes you'll need a different starter, rear engine plate as well as the
later bell housing.

I may have an extra ten bolt style mount plate.

A new or newly built engine is worth the trouble though. Maybe you can
find someone who can use your takeoffs.

Take care,
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wesk
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Post by wesk »

Either bell will bolt to either block! But use care here. A bell used on the block for which it is not made will have some fit and fastening issues.

Disregard the expression waterproof and non-waterproof! Just think of the two style bells as early and late. The late bell and late block have 3 additional bolt holes (5/16") on each side.

Image
Early vs Late front view

Image
Early vs Late rear view

Image
Early vs Late top view

Image
Early vs Late starter mounting dimensions

Image
Early vs Late bell to block adapter plates

Image
Early block rear vs late block rear

The most important thought to keep in your head is what parts must stay together?

1-Bell Housing
2-Adapter plate
3-Starter
4-Flywheel

If you are using an early bell then you must use the early versions of items 2, 3, & 4! If you are using a late bell then you must use the late versions of items 2, 3, & 4!

If you make sure you keep the items 1 thru 4 as a set there are really only two fit or interference problems you must deal with when you deviate from using the correct engine in front of the correct bell.

The issues occur when you use the early bell parts with a late block.

1-The extra meat on the reinforced flange of the late block partially covers the timing mark hole used in the early adapter plate. You can gently grind this meat away from the timing mark port or you can ignore the issue and move the engine timing mark to the front pulley if it isn't already there on the late engine you are using.
2-If you try to using the late engine's larger 129 tooth flywheel with your early bell you will sometimes find the flywheel scrapes the inside of the bell. But since your early starter is suppose to be used with the early 124 tooth flywheel which you should have kept off your old engine you really do not have a problem.
Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100

Mjeeps photo album: http://www.willysmjeeps.com/v2/modules. ... _album.php
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wesk
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Post by wesk »

I an surprised no one has noticed this L134 powered M100 trailer! First time I ever saw one! :wink:
Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100

Mjeeps photo album: http://www.willysmjeeps.com/v2/modules. ... _album.php
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4x4M38
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Post by 4x4M38 »

I was wondering when someone would notice.

Wonder what rear axle it has under it.

(Snicker)
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wesk
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Post by wesk »

I better relocate it to the regular Technical Board!
Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100

Mjeeps photo album: http://www.willysmjeeps.com/v2/modules. ... _album.php
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