In the process of replacing piston/rod #1 due to failed tappet causing valve-piston contact, I am replacing the rings in the rest.
Measuring the ring grooves with the old rings had me worried as a 0.008" feeler gauge easily entered...so I pulled that ring and compared it with a new one. The used ring was indeed 0.003" thinner yet only showed 0.002" had worn from the face that contacts the bore.
Measuring the ring groove with calipers indicates less than 0.001" of wear. Pistons can be reused, at least the ones that didn't contact the valves.
Measuring the ring grooves with the old rings had me worried as a 0.008" feeler gauge easily entered...so I pulled that ring and compared it with a new one. The used ring was indeed 0.003" thinner yet only showed 0.002" had worn from the face that contacts the bore.
Measuring the ring groove with calipers indicates less than 0.001" of wear. Pistons can be reused, at least the ones that didn't contact the valves.