SECTION 4. DISASSEMBLY AND SERVICE
c.CAMSHAFT/ CRANKSHAFT
While installing the camshaft, align the punch marks on
the camshaft gear and timing gear (small gear on the
crankshaft.)
d. INSPECTION
PISTON
Check contact between piston and cylinder, defect of ring grooves, burn of piston top, cracks, etc. If the
damage is severe, such as cracks, replace the piston.
REMOVAL OF CARBON DEPOSIT
Carbon deposit forms on piston top and upper edge of cylinder bore, carbon deposit should be removed
before check. Use kerosene to drench the part with carbon deposit, then use a blunt scraping knife or a wire
brush to remove carbon deposit.
1) PISTON SKIRT O.D.
Use a outside micrometer to measure piston skirt O.D., if it is
out of service limit, replace it.
2) PISTON-TO-CYLINDER CLEARANCE
Difference between cylinder’s maximum diameter and piston skirt diameter is the piston-to-cylinder
clearance.
3) PISTON RING SIDE CLEARANCE
When checking, put all rings in their grooves, they should
be able to rotate freely without loosening or sticking. Then
insert the feeler gauge into clearance between each ring
Standard
Service limit
48.585 mm
48.445 mm
Standard
Service limit
0.03-0.050 mm
0.12 mm
CRANKSHAFT
CAMSHAFT
PUNCH
MARKS
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