Piston Ring Replacement

1.	Remove the piston from the cylinder block.

2.	Using a ring expander (A), remove the old piston rings (B). BA

Clean all ring grooves thoroughly with a squared-off broken ring or ring groove cleaner with a blade to fit the piston grooves.
The top ring groove is 1.0 mm (0.04 in.) wide. The second ring groove is 1.2 mm (0.05 in.) wide. The oil ring groove is 2.0 mm (0.08 in.) wide.
File down a blade if necessary.
Do not use a wire brush to clean the ring grooves, or cut the ring grooves deeper with the cleaning tools.

NOTE: If the piston is to be separated from the connecting rod, do not install new rings yet.

4.	Using a piston, push a new ring (A) into the cylinder bore 15-20 mm (0.6-0.8 in.) from the bottom. AB15-20mm (0.6-0.8 in.)

Measure the piston ring end-gap (B) with a feeler gauge:

If the gap is too small, check to see if you have the proper rings for your engine.
If the gap is too large, recheck the cylinder bore diameter against the wear limits.
If the bore is over the service limit, the cylinder block must be rebored.

**Piston Ring End-Gap:**
Top Ring
Standard (New):	0.15-0.30 mm (0.006-0.012 in.)
Service Limit:	0.60 mm (0.024 in.)

Second Ring
Standard (New):	0.35-0.50 mm (0.014-0.020 in.)
Service Limit:	0.65 mm (0.026 in.)

Oil Ring
Standard (New):	0.20-0.70 mm (0.008-0.028 in.)
Service Limit:	0.80 mm (0.031 in.)

Install the top ring and second ring as shown.The top ring (A) has a R1 mark and the second ring (B) has a R mark. The manufacturing marks (C) must be facing upward.

ABCABTop Ring (Standard):
A: 2.3 mm (0.09 in.)
B: 1.0 mm (0.04 in.)Second Ring (Standard):
A: 3.0 mm (1.2 in.)
B: 1.2 mm (0.05 in.)Piston Ring Dimensions:ABC

7.	Rotate the rings in their grooves to make sure they do not bind.

8.	Position the ring end gaps as shown: DO NOT position any ring gap at piston thrust surfaces.SECOND RING GAPAbout 90°About 90°TOP RING GAPDO NOT position any ring gap in line with the piston pin hole.OIL RING GAPSPACER GAPOIL RING GAP15°15°

After installing a new set of rings, measure the ring-to-groove clearances:

**Top Ring Clearance**
Standard (New):	0.055-0.080 mm (0.0022-0.0031 in.)
Service Limit:	0.15 mm (0.006 in.)

**Second Ring Clearance**
Standard (New):	0.030-0.055 mm (0.0012-0.0022 in.)
Service Limit:	0.13 mm (0.005 in.)