Mitsubishi S4Q2 User Manual

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Service Manual Mitsubishi SQ-Series diesel engines
Version 08/2004
ENGLISH
PISTONS, CONNECTING RODS,
CRANKSHAFT AND CRANKCASE 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:
88 mm [3.46 in.]
0.25 mm (0.0098 in.) oversize gage:
88.25 mm [3.4744 in.]
0.50 mm [0.0197 in.] oversize gage:
88.50 mm [3.4843 in.]
Unit: mm [in.]
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.
Figure 111 Checking clearance between ends of
piston ring
NOTE
Use a piston to place the piston ring in the liner by
pushing it squarely.
Item
Assembly
Standard
Service
Limit
Clearance
between
ends of
piston ring
No. 1, No.
2 ring
0.25 to 0.40
[0.00984 to 0.0157]
0.150
[0.0059]
Oil ring
0.30 to 0.50
[0.0118 to 0.0197]
+0.035
0
+0.0014
0
+0.035
0
+0.0014
0
+0.035
0
+0.0014
0
Figure 112 Measuring piston pin and bore
Measuring directionsMeasuring points

Mitsubishi S4Q2 Specifications

General

Brand	Mitsubishi
Model	S4Q2
Category	Engine
Language	English