Author Topic: Oil leak  (Read 3209 times)

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tyler

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Oil leak
« on: May 24, 2015, 03:09:11 AM »
I have an oil leak on the left side of my 76 CB super sport. The oil is coming from the left rear crankcase bolt head. Any ideas other than pulling the crankcase apart would be great. I was thinking of a bead of hondabond around the bolt shank (before the threads!) where the crankcase clamshells together and let it set up for a day.

Offline Old Scrambler

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Re: Oil leak
« Reply #1 on: June 22, 2015, 11:28:01 AM »
Its more likely to be the gasket at the cover............with oil weeping over to the bolt before it 'drips' on your nice clean garage floor. Often the result of parking the bike on the side-stand for extended time periods. It won't hurt to check the cap-bolt. I've successfully installed a 'half-slice' of a grommet to stop more than one oil leak.
Dennis in Wisconsin
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Offline MCRider

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Re: Oil leak
« Reply #2 on: June 22, 2015, 11:29:57 AM »
Has the engine ever been apart before?
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Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Oil leak
« Reply #3 on: June 22, 2015, 11:42:04 AM »
+1 with Dennis.

Is it trailing down from the area of the dowel?

It could be from the crank shaft bolts as you mention but not likely unless the engine has been apart and sealant was not properly put around the mating surface around the bolt hole in the case halves. I just put cases together yesterday and in addition to placing sealant where I mentioned I also put some under the washer and nut (I replaced the 8mm bolts with studs and have to use nuts) as in your bolt picture with the oil drop.
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