Piston Ring: Service and Repair
REMOVAL1. Remove the pistons and connecting rods.
CAUTION: Do not remove the oil scraper ring with the pliers. The oil scraper ring must be removed and installed by hand.
2. Using piston ring pliers, remove the piston rings.
CAUTION: Do not cut or scratch pistons while cleaning.
3. Use a ring grove cleaner or a broken ring to remove deposits in the ring grooves.
4. Inspect the pistons for heat scoring and distortion at the piston pin openings and piston skirts. Replace as required.
INSTALLATION
1. Measure the end gap (1) with rings at the bottom of the cylinder.
^ Ring # 1 clearance is 0.20 mm to 0.35 mm.
^ Ring # 2 clearance is 0.20 mm to 0.40 mm.
2. Measure the vertical clearance (2) of the piston rings (1).
3. Ring # 1 clearance is 0.012 mm to 0.060 mm.
4. Ring # 2 clearance is 0.010 mm to 0.030 mm.
5. Install the rings on the pistons as shown.
^ Compression ring (1)
^ Sealing ring (2)
^ Oil Ring Rail (3)
^ Oil Ring Expander (4)
6. The ring gaps when installed must be positioned as shown.
^ Ring one (1)
^ Upper side rail (2)
^ Ring two and spacer expander (3)
^ Lower side rail (4)
7. Install the pistons and connecting rods.