M38 Rear Carrier Bearing Caps

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Mike_B
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M38 Rear Carrier Bearing Caps

Post by Mike_B »

So, I just opened my M38 rear axle for a quick inspection and a change of oil. Everything looks nice and clean with good wear patterns on the gears.

I noticed the Carrier Bearing Caps are installed 180* from where I think they should be. The letter used is "Y" and on one side the letter is vertical and the other side horizontal, but the letters (cap vs housing) are not straight across from each other.

Image
Mike, I downloaded your 3.9Meg & 3.7 Meg photos reduced their file size to less than 1 Meg, combined them and added the yellow circles. Then I loaded them to your photo album in our "Member's Albums page
Should I flip the caps over to line the letters up to each other or should I leave it alone?

Thanks,

Mike B :)
Mike B
1953 M38A1 Brush Truck
1952 M38
1951 M100 Trailer
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wesk
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Post by wesk »

Mike, This would be a very good place to post a photo of the Letter Y's you are referencing.

There should have been match marks in the cap that aligned them with the correct side seat in the correct vertical orientation. These match marks are important. Just like matching rod caps to their rods.
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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Mike_B
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Post by Mike_B »

Pictures would help, but...

So, the Y's on the drivers side are both in the vertical position, but the one on the case is near the bottom bolt and the one on the cap is upside down near the top bolt.

The passenger side both are horizontal with the case stamped at the bottom bolt and the cap stamp is reversed (tail of the Y facing the opposite direction) at the top bolt.

With that said I believe the caps are on the correct side, but are both 180* out of position. So the question is, is there any harm in flipping the caps to their original factory position or should I just leave it be?

Thanks!

Mike B :)
Mike B
1953 M38A1 Brush Truck
1952 M38
1951 M100 Trailer
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wesk
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Post by wesk »

My question remains the same. Post photos of the Y's and any man made match marks. Match marks are filed grooves or pin punched holes arranged to indicate the cap's original position relative to the mounting surface. Without the photos I cannot offer any reliable advice on your situation!
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 loaded your photos to your post and annotated them accordingly.

Yes the "Y"'s appear to be cap positioning match marks.

Since you have no way to determine the age of the bearings we must assume they have worn significantly and now have their own set. If you are concerned over their alignment and do not indicate any problems mechanically with the axle assembly I would leave them as they are. If you simply must correct their positioning for some reason then the best advice is install new bearings first then align the marks.
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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Mike_B
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Post by Mike_B »

Thanks Wes!

Mike B :)
Mike B
1953 M38A1 Brush Truck
1952 M38
1951 M100 Trailer
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