Check for ring grooves in the cylinder bores and worn out bearings or wear on the crank like you would with any other motor. Since it was sprayed look at the pistons and see if you see any small bubbles or pock marks from it getting too hot. These will usually show up around the edges of the pistons where the metal is thinnest. With any sort of "unknown" motor like that I would at least re ring it and put in new bearings.
<font size=-1>[ This Message was edited by: Hottarod on 12/25/01 10:53am ]</font>