Piston Rings - Pistons - Piston Pins - Kohler KD 477-2 Workshop Manual

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KD 477-2 Workshop Manual_cod. ED0053029370_1° ed_ rev. 00

Piston rings - Pistons - Piston pins

Check the wear of piston rings by fitting them into the cylinder throu-
gh the lower end and measuring the end gap (fig.17). The values
should be:
Piston ring Fitting mm
Compression 0,30
0,25
Oil scrapper
Check that the rings move freely in the grooves and check the ring/
groove clearance using a feeler gauge (fig.18).
If the clearance exceeds the values shown in the table, renew the pi-
ston and the piston rings.
Piston ring
1 Compression
st
2 - 3 Compression
nd rd
4 Oil scrapper
th
Piston rings must always be renewed after dismantling the
piston.
Piston diameter check: The diameter of the piston must be measured
at approximately 18 mm from the base (fig.19).
Engine
KD477-2
Check the clearance between cylinder and piston, if it is greater than
0.120 mm both cylinder and piston must be replaced.
Assembly clearance between piston pin and piston in millimetres:
Fitting mm
0,001 ÷ 0,010
CHECKS AND OVERHAUL
Max. wear mm
÷ 0,50 0,80
÷ 0,50
0,80
Max. wear mm
A = 0,22
B -C= 0,18
D = 0,16
Diameter mm
89,919 ÷ 89,930
Max. wear mm
0,060
X
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