Sorry to read that you forgot to measure that crankshaft before you got it back together.

My intent was to raise the question of the Volvo seal and having only a part number on their seals. I wondered if they had an exclusive on that particular dimension. That is why I measured things. Old work habit too!

My thought is that 92 mm is a nominal size. But then we are in the USA. I’m still waiting for the conversion since the late sixties.

For the seal industry, I think would be a little foolish. But then again we did help (along with the Europeans) invent the idea of special odd stuff so we get return business long ago.

Standards are just as elusive as a 2x4. It is really 1.625 x 3.625 or as substandard old fractional system. Eighths are even hard to type in! Sure has helped us when the stock market finally changed to catch up with the rest of the globe!

The plumbing trade beats everyone in the standards category. Oddest sizes for everything, then they throw in the thinnest cheapness material to boot!

If I have still have the same burning interest when I visit the bearing house I'll be more persistent for some information on what other makers provide.

Viton is a better wear resistant and heat tolerable material. Especially at the point of the lip sealing contact and the friction generated there. That is according to the technical sheets I’ve read.

As far as the rear seal being hotter than the front is a good wonderment, again!
If you think about it though, a clutch or torque converter is working, zapping away horsepower with internal friction. Auto V/s manual again.

Loss of energy can be found where there is heat. The exhaust trail is an easy place to spot.

There could be more heat from the drive train hanging about around there just because of the mass and the work being performed.

I feel that there is more oil at the rear. Most of the time, it is due to the engine working the hardest under acceleration and hills. Lower gears and higher revs compared to downhill coasting and such conditions.

The rear seal is larger than the front so that means there is more circumference to contend with when it comes to designing. I think there is an oil slinger affair at the rear to help compensate. Don't know about the front per say.

Thanks for thinking of my post during your activities.

Phil

I recently replaced my rear main seal '89 200 B230:
Not sure what the dimension of the original 'ANGUS' Seal was;the seal I bought from Groton has no dimensions on it either. Just a number SOMO5852. The only observation I can make is that The Inner diameter had to deflect a lot to fit around the Crank so with that much of the seal stretching back to fit over the Crank, I don't think if it was the 93mm, it would make a difference, it should seal very well.
The OEM seal has some numbers on it but nothing representing diameters of the seal.
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'75 Jeep CJ5 345Hp ChevyPwrd, two motorcycles, '85 Pickup: The '89 Volvo is the newest vehicle I own. it wasn't Volvos safety , it was Longevity that sold me http://home.no.net/ebrox/Tony's%20cars.htm

I've been using the OEM seals made by Elring on B18s, B20s and B30s for years and
and have never seen one get hard like you describe. I wonder if you somehow got a dud....
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George Downs, Bartlesville, Heart of the USA!

I do not have the answer to your question about sizes.I followed the other posts regarding oil seals and I have thoughts and questions about how to possibly prolong the life of either type of seal,be it with additives,treatments, oil types,or oil change frequency,I'm sure temperature also plays a big part.Where does all this information go?(never mind ,I just read all the information on rear main seal replacement in the 7/9 FAQ section).
Great web site,I think its time I make a new years donation to the Brickboard.
Thanks all