Taken from another post:
NEVER USE SCOTCHBRITE TO CLEAN UP GASKET SURFACES OF AN ENGINE.
NEVER, EVER, EVER USE SCOTCHBRITE ON AN ENGINE. At least not one you want to run again for a long time.
Scotchbrite seems so benign but it is death to engines. Scotchbrite pads are nylon fibers with 40 micron particles of aluminum oxide in them. Scotchbrite dust leaves behind all those 40 micron particles hidden everywhere. Aluminum oxide is an extremely aggressive abrasive. It imbeds in the bearings and eats the crank....and other things.
Scotchbrite is the bane of the aftermarket re-man engine industry. There are lots of "new" re-mans ruined by cleaning up the old parts with scotchbrite pads and then installing them. Eats up the engine immediately. That is why many engines fail the main and rod bearings after a head job or other work...scotchbrite. People think it is because of coolant getting into the oil ruining the bearings or something when it was really the scotchbrite the mechanic used to clean up the parts... especially a Northstar engine where the block deck surface cleaning funnels the scotchbrite dust down the oil drain back passages.
If you cleaned up parts with scotchbrite you now have a HUGE cleanup job ahead of you cleaning up after the scotchbrite. You must make positively sure that none of the dust remains anywhere on any parts or got into the oil cavity. Hopefully the valley of the engine was covered if you used scotchbrite on the deck surface as if it drifted into the valley or into the pan your engine is toast.
I am very very serious about this. Scotchbrite has a very bad reputation in the industry as it seems like such an ideal cleanup method, seems so benign, yet can cause such extreme damage. Most mechanics in the know stay miles away from scotchbrite as it is harder to clean up after it than any labor it saves.
If you doubt this at all call JASPER or any of the main engine re-man companies and ask them if it is OK to use scotchbrite to clean up the manifold you are going to put on your Jasper re-man....
