Calculating The Piston-To-Cylinder Clearance; Checking The Piston Pins And Small-End Bearings - Yamaha e60hmhd Service Manual

CRANKSHAFT ASSEMBLY AND CYLINDER BODY
CHECKING THE PISTON
Measure:
• Piston diameter
(with a micrometer)
Out of specification
Measuring
point "H"
10 mm
Standard
(0.4 in)
Over size piston diameter:
1*: 72.25 mm (2.844 in)
2: 72.50 mm (2.854 in)
*: Except for USA
NOTE:
When measuring the piston diameter,
position the micrometer in relation to the
piston pin hole as shown.
CALCULATING THE PISTON-TO-
CYLINDER CLEARANCE
Calculate:
• Piston-to-cylinder clearance.
(with a micrometer)
Out of specification
piston and piston rings, the cylinder or
both.
Piston-to-
cylinder =
clearance
Piston-to-cylinder clearance:
0.055 - 0.060 mm
(0.0022 - 0.0024 in)
CHECKING THE PISTON PINS AND
SMALL-END BEARINGS
1. Check:
• Piston pin
• Small-end bearing
Heat discoloration
Damage/scratches
5-39
Replace.
Piston diameter
71.940 - 71.956 mm
(2.8323 - 2.8333 in)
Replace the
Cylinder bore Piston
—
diameter diameter
Replace.
Replace.
E