(3) The clearance is computed by sub-
tracting the piston outside diameter
from the cylinder liner inside diame-
ter. Replace either piston or cylinder
liner, whichever damaged more, if
the clearance is beyond the specified
limit.
3.2.9. Piston rings
1) Replace the piston rings with new ones if
detected worn or broken when the
engine is overhauled.
2) Measure piston ring gap.
(1) Insert the piston ring into the upper
portion of the cylinder liner bore so
that it is held at a right angle to the
cylinder liner wall.
(2) Measure the piston ring gap with a
feeler gauge.
(3) Replace piston rings with new ones if
the gap is beyond the limit.
3) Measure piston ring side clearance.
(1) Fit the compression ring and oil ring
in the piston ring groove.
(2) With a feeler gauge, measure side
clearance of each ring, and replace
either the ring or piston if the mea-
sured value is beyond the specified
limit.
Dimensions
Standard(mm) Limit(mm)
Descriptions
Top ring
0.40~0.65
1.5
2nd ring
0.40~0.65
1.5
Oil ring
0.30~0.60
1.5
Liner
Standard
Limit
Cylinder line
inside diameter
l
123
+0.005
123.225
(mm)
- 0.015
- 58 -
EFM2053I
<Figure 3-25> Measuring piston ring gap
