F510 & F525 Cylinder Block – REMOVE AND INSTALL PISTON RINGS
1. Remove piston rings with a piston ring expander.
2. Inspect piston. Clean piston ring grooves. (See Inspect Piston in this group.)
3. Check piston ring end gap. (See Check Piston Ring End Gap in this group.)
4. Install top ring (A) and second ring (B) with R or NPR mark facing up. Rings should turn freely in grooves.
5. Oil ring is an assembly. Install spacer (C), then side rails (D). Put side rail end gaps 180 ̊ apart.