Check each piston for scuffing, scoring wear, and other defects. Replace any piston that is defective.
Check each piston ring for breakage, damage and abnormal wear. Replace the defective rings. When the piston requires replacement, also replace the rings.
Check the piston pin fit in the piston pin hole. Replace any defective piston and pin assembly that is defective. The piston pin must be smoothly pressed by hand into the pin hole (at room temperature).
Measure the piston ring side clearance. If the measured value exceeds the service limit, insert a new ring in a ring groove to measure the side clearance. If the clearance still exceeds the service limit, replace the piston and rings together. If it is less than the service limit, replace only the piston rings.
Piston ring side clearance
Standard value
No. 1
1.3 L : 0.04 ~ 0.085 mm (0.0016 ~ 0.0033 in.)
1.1 L : 0.03 ~ 0.07 mm (0.001 ~ 0.003 in.)
No.2
1.3 L : 0.04 ~ 0.085 mm (0.0016 ~ 0.0033 in.)
1.1 L : 0.02 ~ 0.06 mm (0.0007 ~ 0.0024 in.)
Limit
No. 1 : 0.1 mm (0.004 in.)
No. 2 : 0.1 mm (0.004 in.)
To measure the piston ring end gap, insert a piston ring into the cylinder bore. Position the ring at right angles to the cylinder wall by gently pressing it down with a piston Measure the gap with a feeler gauge. If the gap exceeds the service limit, replace the piston ring.
Item | Standard - mm (in.) | Limit - mm (in.) |
Piston ring end gap No.1 1.3 L 1.1 L | 0.20 ~ 0.35 (0.0079 ~ 0.0138) 0.15 ~ 0.30 (0.0059 ~ 0.0118) | 1 (0.039) |
Piston ring end gap No.2 1.3 L 1.1 L | 0.37 ~ 0.52 (0.015 ~ 0.02) 0.30 ~ 0.50 (0.012 ~ 0.02) | 1 (0.039) |
Oil ring side rail end gap | 0.20 ~ 0.70 (0.078 ~ 0.0275) | 1 (0.039) |
When replacing the ring without correcting the cylinder bore, check the gap with the ring positioned at the bottom of the ring travel.
When replacing a ring, use a ring of the same size.
Piston ring service size and mark
STD : None
0.25 mm (0.010 in.) O.S. : 25
0.50 mm (0.020 in.) O.S. : 50
0.75 mm (0.030 in.) O.S. : 75
1.00 mm (0.039 in.) O.S. : 100
The mark can be found on the upper side of the ring.
