Crankcase (Cylinder) Inspection; Piston And Piston Pin Inspection - Yamaha EF3000iSE Service Manual

PISTON, CONNECTING ROD, CRANKSHAFT AND
CRANKCASE

CRANKCASE (CYLINDER) INSPECTION

1. Measure:
• Cylinder inside diameter
NOTE:
Take side to side a and front to back b mea-
surements at each of the three locations A, B,
and C (total of six measurements), and then
find the average of the measurements.
Maximum wear = Maximum A, B, C
Cylinder taper = Maximum A – Minimum C
Out of specification → Replace.
Cylinder inside diameter:
Cylinder inside diameter wear
limit:
Cylinder taper limit:
SVU3590
2. Measure:
• Cylinder warpage
NOTE:
Measure the warpage on the contact surface
of the cylinder head at six points using a
straightedge and thickness gauge.
Out of specification → Resurface or
replace.
SVU3580J
Warpage limit:

PISTON AND PISTON PIN INSPECTION

1. Measure:
• Piston skirt diameter P
a
= 10 mm (0.4 in) from the piston bottom edge
Out of specification → Replace.
Piston skirt diameter:
Wear limit:
SVU3590J
3-38
ENG
66.005 ~ 66.015 mm
(2.5986 ~ 2.5990 in)
66.020 mm (2.5992 in)
0.05 mm (0.0020 in)
0.05 mm (0.0020 in)
65.975 ~ 65.990 mm
(2.5974 ~ 2.5980 in)
65.9 mm (2.5945 in)