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General Tech Back to Viton and Mad Marx

KVH

Obi Wan
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Well, I'm about ready to install the new rear main seal, but the centering tool is measuring about .0114 larger than the machined end of my crank. Is that OK, expected? I would've thought they'd be the same. Is something wrong do you suppose?
 
Actually, accounting for human error in my measurement, and looking at the two dimensions by Christian Marx in his instructions and update he posted in this forum, the centering must deliberately leave clearance. I think I must be close enough.
 
Doesn't sound right. What measurements did you get? The mandrel should be 2.818", while the old crank I just checked is 2.812 (give or take a few tenths)

When you say "machined end", do you mean the scroll area? The Viton seal is intended to be used with the original crank scroll intact (but would probably still work OK without it).
 
The Viton seal is intended to be used with the original crank scroll intact (but would probably still work OK without it).

Never thought about it and I'll now have to see if the new MM Viton seal kit will work OK on an already machined off crank scroll that I have from the Rover seal design.

Now back to the thread ...
 
(but would probably still work OK without it).
After thinking about it, and checking the photo in the instructions; I take that back. The lip seal rides on the smooth surface just behind the scroll, which was originally machined to the same diameter as the scroll. Most likely, when the shop machines off the scroll, they will take that area off as well.

untitled.jpg~original
 
Doesn't sound right. What measurements did you get? The mandrel should be 2.818", while the old crank I just checked is 2.812 (give or take a few tenths)

When you say "machined end", do you mean the scroll area? The Viton seal is intended to be used with the original crank scroll intact (but would probably still work OK without it).

I rechecked. I'm right on with what you have. I came up with 2.810 on the crank, but I'm learning that even a micrometer takes some skill.

I seem always to get stuck on some other issue. I found a post advising that "liquid silicone" be used on the rear main seal, but others suggest something easier to brush on, like High Tack or Wellseal. I've got more tubes of different kinds of silicone than I care to count, but a tube "paste" product just doesn't sound right for metal to metal faces. I'd have to smear it all around with a putty knife of something like that. Any more advice on the adhesive?
 
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