Farm Equipment - 1938 b front crank seal

1938 b front crank seal

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Category: Allis Chalmers
Forum Name: Farm Equipment
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URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=142851
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Topic: 1938 b front crank seal

Posted By: archangel_cpj
Subject: 1938 b front crank seal
Date Posted: 26 Sep 2017 at 10:01am

Hi I'm going to need to replace my b front oil seal and in reading here I keep seeing a speed seal or bushing To cover the groove in the crank... so where do I get one and what size??? Also anyone on here sell just the timing cover gasket????

Replies:

Posted By: Brian Jasper co. Ia
Date Posted: 26 Sep 2017 at 12:19pm

I can tell you that 20 some years ago when I overhauled my CA, (same basic engine) it got an ordinary lip seal and I never installed a speedy sleeve on it. Just leave the cover in place and drive in a new seal. There are no dowel pins to line up the cover. There is a special tool that slips over the crank and uses the seal opening to line up the cover. When I did mine I didn't have the tool so I installed the seal in the cover, stood the engine on the flywheel and let the seal center the cover.

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"Any man who thinks he can be happy and prosperous by letting the government take care of him better take a closer look at the American Indian." Henry Ford

Posted By: CrestonM
Date Posted: 26 Sep 2017 at 1:52pm

I did almost the exact same thing as Brian last year on my 1942 B. Mine had the spiral as well, and I didn't sleeve it. I don't CA's ever had the groove in the crank, so you will probably have to sleeve it or do something like I did.

I'm cheap, so I followed some advice and filled in the groove with JB weld. Let that dry, then just filed it down even with the crankshaft. The JB weld just fills in the groove so oil doesn't run out; the seal doesn't ride on it, so you don't have to worry about it wearing down.

My engine was in the tractor though, so I just stuck the cover on and eyeballed it as best I could. After tightening it down, I could tell it was a hair off, but I was reassured it would still work as long as it's pretty close, and it's still leak free today. Words can't describe how proud I was to not have to stick a catch pan under the engine as soon as I shut it off.

Oh...one other thing....the early B's (mine included) have a smaller hole in the timing cover for a smaller seal. From what I could find, only the newer, larger seal is available. I picked one up at Hutch from DJ's. I just used a Dremel to grind out my hole so the new seal could press in. Naturally, the enlargement I did wasn't perfectly round, so I pressed in the seal and ran a small bead of sealant around its circumference.

That's one thing I like really about the B engines. The crank seals are pretty easy to replace. Lip seal on front and 1 piece felt seal on back. None of those cursed rope seals, like my 8N has.