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Crankcase blowby
- cbclemmens
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Crankcase blowby
Does anyone know any way to mitigate this without pulling the jugs and installing a new base gasket? I really don't want to tear it down as it is running very well.
I think I already know the answer.
Craig
- schrader7032
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Re: Crankcase blowby
'78 R100/7 '69 R69S '52 R25/2
Fast. Neat. Average. Friendly. Good. Good.
Re: Crankcase blowby
Barre, MA USA
1963 R60/2 w/ 1955 Steib S500
1973 R75/5
- cbclemmens
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Re: Crankcase blowby
Craig
- cbclemmens
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Re: Crankcase blowby
Craig
- cbclemmens
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Re: Crankcase blowby
Craig
- cbclemmens
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Re: Crankcase blowby
I ordered rings and gaskets from Max. Looks like my R75/5 will be down for a few weeks. It might be longer as I'm having minor surgery next week. Craig
- srankin
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Re: Crankcase blowby
Makes sense, if there is excessive internal pressure and it is not vented, the pressure has to go somewhere and that will be the path of least resistance.
Check out snowbum's website, I bet he has written about this topic. Good luck, St.
- cbclemmens
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Re: Crankcase blowby
Does anyone see a flaw in my thinking?
Craig
- srankin
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Re: Crankcase blowby
With good compression, and properly torqued heads and other good stuff, I hate to repeat myself but I still question the pop off valve on the blocks shape.
I mean I am assuming you are not blowing oil out the exhaust but as written, it is seeping out the base of the jugs. I would be concerned with rings, valves and such only if I had low compression, blue smoke, black oily plugs or some hint the oil was ending up being burned. Pushing oil past the seals makes me think the block is not venting off the pressure.
Then again that is me and my opinion. During the winter there is nothing to say things can't be torn down, checked and rebuilt. LOL, it gives me something to do when I can't ride. St.