[jhg41977]

I am rebuilding the engine in my 993 and the chain boxes show some pitting where the seal to the cover sets. The covers also show similar marks, although more like chipping, where the seal sets into the groove. The rest of the boxes and covers look fine. I washed them initially in a parts washer which has only had econosolve in it. I believed these to be aluminum and econosolve is safe for use on aluminum per the manufacturer. The marks were visible before cleaning, so I do not believe these to be related to cleaning. I used a brass brush in the seal grooves while cleaning.

So, what to do. Do I add a sealant? Can I lightly sand the groove in the cover smooth or at least smoother? Do I do both?

I would love to just replace the boxes but they are not cheap. I have looked on ebay but have not been able to find a complete set.

Thanks
Jim