CHECKING THE PISTON RINGS
1. Measure:
• piston ring side clearance
Out of specification → Replace the piston
and piston rings as a set.
Before measuring the piston ring side clearance,
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 → 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
0.15 ~ 0.30 mm
(0.0059 ~ 0.0118 in)
<Limit>: 0.45 mm (0.0177 in)
2nd ring
0.30 ~ 0.45 mm
(0.0118 ~ 0.0177 in)
<Limit>: 0.60 mm (0.0236 in)
<Limit>: 0.40 mm (0.0157 in)
Oil ring
0.20 ~ 0.80 mm
(0.0079 ~ 0.0315 in)
CYLINDER AND PISTON
ENG
TIP
TIP
TIP
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