Started stripping the donor down. Pulled the bypass covers off and piston 1 has most of the top ring gone. The rest of the pistons have unbroken rings. All pistons are very loose in bore, but how loose is too loose? I think this pig has been repaired before.
Here are the heads. Hole 1 has minor ring dent damage, 3 has significant prior damage and evidence it was smoothed a bit for a prior repair. Port head gasket is blown between cylinders 2 and 4. Starboard gasket is OK.
Here's number 1 at bottom. Evidence of ringstrike at the exhaust port. Probably didn't help that the water deflecor is blocking flow, right?
Here's number 3 at bottom. No evidence of ring bits coming through the piston crown.
Here's number 2 at bottom. No evidence of damage on piston or head.
Here's number 4 at bottom. No evidence of damage on piston or head.
Got the bubble off. Center bolt (the really long one that's only accessible once the back cover is off) was very loose. Doesn't appear to be any evidence of gasket leakage or casting erosion.
Here's number 1 at top. Some small holes around the crown where the top ring bits came through.