Remove
Remove piston with con-rod – see operation "Piston with Con-rod, Remove and Install". Remove piston rings with piston ring pliers (1).
Clean
Clean piston ring grooves – use ground-down side of old piston ring.
Inspect
Check piston ring gap clearance with feeler gauge. Insert new piston ring at narrowest point in cylinder bore.
| Permissible ring gap | |
|---|---|
| Squared ring (2) | 0.3 to 0.5 mm |
| Tapered ring (3) | 0.3 to 0.5 mm |
| Oil scraper ring (4) | 0.4 to 1.4 mm |
Inspect
Check piston ring vertical play with feeler gauge in piston ring groove.
| Permissible vertical play | |
|---|---|
| Squared ring (1) | 0.02 to 0.04 mm |
| Tapered ring (2) | 0.02 to 0.04 mm |
| Oil scraper ring (3) | 0.01 to 0.03 mm |
Install
Insert new piston rings into piston with piston ring pliers and with identification "TOP" on top. Piston ring position – piston rings (I) every 120°. Oil scraper rings (II) – offset 25 to 50 mm to left and right from gap in intermediate ring.
Install piston with con-rod – see operation "Piston with Con-rod, Remove and Install".
