CHECKING THE PISTON RINGS
1. Measure:
• piston ring side clearance
Out of specification
ĺ
Replace the piston
and piston rings as a set.
Before measuring the piston ring side clear-
ance, eliminate any carbon deposits from the
piston ring grooves and piston rings.
2. Install:
• piston ring
(into the cylinder)
Level the piston ring into the cylinder with the
piston crown.
3. Measure:
• piston ring end gap
Out of specification
ĺ
Replace the piston
ring.
The oil ring expander spacer’s end gap cannot
be measured. If the oil ring rail’s gap is exces-
sive, replace all three piston rings.
Piston ring side clearance
Top ring
0.015 ~ 0.055 mm
(0.0006 ~ 0.0022 in)
<Limit>: 0.09 mm (0.0035 in)
2nd ring
0.015 ~ 0.055 mm
(0.0006 ~ 0.0022 in)
<Limit>: 0.09 mm (0.0035 in)
Piston ring end gap
Top ring
0.10 ~ 0.25 mm
(0.0039 ~ 0.0098 in)
<Limit>: 0.45 mm (0.0177 in)
2nd ring
0.25 ~ 0.40 mm
(0.0098 ~ 0.0157 in)
<Limit>: 0.55 mm (0.0217 in)
Oil ring
0.20 ~ 0.70 mm
(0.0079 ~ 0.0276 in)
ENG
4 - 24
CYLINDER AND PISTON
TIP
TIP
TIP
