1988 CR80 eating crank seals

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Jan 2, 2002
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#1
The boys 1988 CR80 has ran awesome till last month. Got the bike in November last year. The top and bottom end have both been rebuilt. The crank has no play at all. All of a sudden it won't hold a seal on the right side for nothing, not even the carbon fiber double lip Teflon seal. I have a vise grip dial indicator on it's way from Harbor Freight. Is there any chance this might be the factory crank and be worn out at the lip sealing area?
 

jaguar

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#2
the only difference between left and right seals is that the right seal contacts transmission oil so maybe you should consider that maybe the oil is not the right type or maybe there are metal bits floating in it. You can JBWeld a small magnet to the drain plug to catch all metal bits that are steel. It won't catch aluminum.
But yes the crank could be worn down there where the seal touches it.
 
- a d v e r t i s e m e n t -

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Jan 2, 2002
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#3
the only difference between left and right seals is that the right seal contacts transmission oil so maybe you should consider that maybe the oil is not the right type or maybe there are metal bits floating in it. You can JBWeld a small magnet to the drain plug to catch all metal bits that are steel. It won't catch aluminum.
But yes the crank could be worn down there where the seal touches it.
The crank has some marks on it making it look older. Just hope I don't have to buy one cause it's trail riding season for us here in Arkansas since the weather is starting to cool down. The micrometer and dial indicator should tell the truth. Thanks for your reply
 
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#4
What do the crank main bearings look like? Is there any end play at the crank ends, or any movement of the bearing outer shell in the case?