Doosan DX60R Shop Manual page 323

6. Measure the diameter of the wrist pin bore on both sides
of the piston (Figure 195). See "Piston" on page -98 for
specifications. Record the measurements.
7. Measure the outside diameter of the wrist pin in three
places and at 90° (Figure 196). See "Piston" on page -98
for specifications. Record the measurements.
8. Using a micrometer, measure the thickness of each piston
ring. See "Piston Ring" on page -99 for specifications.
Record the measurements.
NOTE:
On an engine with low hours, the pistons, piston
rings and cylinders may be reused if they are
found to be within specifications.
On an engine with high hours, the pistons rings
should be replaced and the cylinder honed (See
"Honing and Boring" on page -147) or replaced.
The piston should be replaced as necessary.
9. Place each compression piston ring in the groove as
shown (Figure 197). Use a feeler gauge to measure the
clearance between the piston ring and the piston ring
land. Record the measurements. See "Piston Ring" on
page -99 for specifications. Replace the piston if not within
specification.
10. To measure piston ring end gap, insert each compression
piston ring (1, Figure 198), one at a time, into the cylinder.
Use a piston with the piston rings removed to slide the ring
into the cylinder bore until it is approximately 1.18 in. (30
mm) (2, Figure 198) from the bottom of the bore. Remove
the piston. Measure the end gap (3, Figure 198) of each
piston ring. Record the measurements. See "Piston Ring"
on page -99 for specifications.
NOTE: Always check the piston ring end gap when
installing new piston rings. See "Piston Ring" on
page -99 for specifications. Use a piston ring
end gap filing tool to adjust the piston ring end
gap on new piston rings.
11. Repeat the above steps for each cylinder and piston
assembly.
Engine
Figure 195
Figure 196
Figure 197
Figure 198
FG008944
FG008945
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