Mitsubishi S4Q User Manual page 66

PISTONS, CONNECTING RODS,
CRANKSHAFT AND CRANKCASE
Figure 111 Checking clearance between ends of
piston ring
Measuring points
Figure 112 Measuring piston pin and bore
66 / 174
Measuring directions
ENGLISH
ENGINE MAIN PARTS
2) Install a new piston rings and recheck the
clearance. If the clearance still exceeds the
service limit, replace the piston.
3. Checking clearance between ends of piston ring
Install the piston ring in a new cylinder or a gage
and measure the clearance between the ends of
the ring with a feeler gage. If the clearance
exceeds the service limit, replace all piston rings.
Inside diameters of gages
Standard gage:
+0.035 +0.0014
88 mm [3.46
0 0
0.25 mm (0.0098 in.) oversize gage:
+0.035
88.25 mm [3.4744
0
0.50 mm [0.0197 in.] oversize gage:
+0.035
88.50 mm [3.4843
0
NOTE
Use a piston to place the piston ring in the liner by
pushing it squarely.
Item
No. 1, No.
Clearance
2 ring
between
ends of
Oil ring
piston ring
4. Checking clearance between piston pin and bore
Measure the inside diameter of the pin bore of the
piston and the diameter of the pin, as shown in the
illustration, to check the clearance. If the clearance
exceeds the service limit, replace the parts.
Service Manual Mitsubishi SQ-Series diesel engines
in.]
+0.0014
in.]
0
+0.0014
in.]
0
Unit: mm [in.]
Assembly Service
Standard Limit
0.25 to 0.40
[0.00984 to 0.0157]
0.150
[0.0059]
0.30 to 0.50
[0.0118 to 0.0197]
Version 08/2004