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Meo9979

1995 Yamaha Big Bear 350 - Crankcase cleanup for assembly

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Hey there,

I splitted open my crankcase on my big bear to change my shift drum that broke :confused:. Now I'm at the step where I'd like to clean both sides of the crankcase & clutch cover, first thing being to remove the old gasket sticked there.

I think I messed up by trying to be quick & used a copper brush on a power drill to brush it off:frown:... I know that copper is softer than metal, but did I just screw up my aluminum crankcase edges by doing that? Or will it be ok with a proper gasket that I'm about to order?

Also, doing that left some residues inside the crankcase half, I was wondering if I can clean the interior of the crankcase (bearings still installed inside) with some water? I think I read somewhere that you can do that if you take care of drying out the bearings with compressed air and oiling them up with engine oil afterwards.

Thanks for any help!

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i think you are ok with the copper brush, i would use some rtv blue or black gasket maker along with the gasket you are getting. i would tend to use some carb cleaner or brake cleaner in an aerosol so it cleans and dries quickly ...

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