Topic: Oil in cb-750 alternator cover

[Z0wner]

Hey guys, I'm new here and have been lurking for a while now.
I feel pretty stupid, but I had an oil leak coming out the left side alternator cover. I went to a mechanic and he told me oil was not even supposed to be in that area. I found myself wondering why Honda would use gaskets between the said cover and the rest of engine. He told me their were oil seals keeping oil out of the region.

So, this 'oil leak,' spurred me to open up the side cover and take a look for myself. I was told the seals were behind the alternator rotor, so ended up pulling the rotor off (what a bear) and there was nothing. 


click for larger image


click for larger image

My question is then: is oil supposed to be in that region. It would appear to be due to the hole highlighted in the picture and the gasket used from the factory. Will replacing the side cover gasket take care of this problem, then?

Thanks for reading.

(btw, it's a 1978 cb750F SS)

[bryanj]

Youre mechanic dont know his arse from his elbow! Oil is there in 750, not in 550/500.

New gasket with clean surfaces and seal the rubber wire grommet with a SMALL amount of silicone----WITH NONE SQUEEZING INWARDS!!!!!!----

[Z0wner]

Man do I wish I would have come here before taking off that alternator rotor. I caused more damage doing that than anything else. Damaged the alternator rotor itself, and partially stripped the interior of the crankshaft end in the process. 

Stupid mechanic.

Thank you for the quick response! Much appreciated.

I feel like this is a dumb question, but which/where/what is the rubber wire grommet?
I have a gasket for the cover, but it is definitely some type of marbleized green/white rubber.

[Alan F.]

The grommet BryanJ's refering to is on the wiring that exits the cover, seal it with a little silicone but be sure none squeezes inside the cover, it'll get carried around by your oil until it clogs a tiny port somewhere and that'll kill your engine in short order, so be careful.

[Johnie]

Here is a pic of the grommet in question.  They can be a source of a leak that can be a real pain in the butt.

[Z0wner]

Man, this forum is awesome!

Thanks :-D

[MCRider]

Man do I wish I would have come here before taking off that alternator rotor. I caused more damage doing that than anything else. Damaged the alternator rotor itself, and partially stripped the interior of the crankshaft end in the process. 

Stupid mechanic.

Thank you for the quick response! Much appreciated.

I feel like this is a dumb question, but which/where/what is the rubber wire grommet?
I have a gasket for the cover, but it is definitely some type of marbleized green/white rubber.

Sorry for your experience with bad advice. You were right why would there be a gasket there otherwise? Its not a lot of oil, but everything in there is bathed in a mist. Starter gears, clutch, etc.

As to the grommet, I think 3bond type gasket sealer works and relieves the anxiety of using silicone. But if you're stingy with the silicone its fine.

If your gasket is old and dried out, some oil between your fingers rub it all around will perk the gasket up. A little 3 bond will give it some compliance, but in a perfect world all the gaskets can be used dry.