Piston Pin And Small End Bearing; Crankshaft; Cleaning; Inspection - Yamaha 25J Service Manual

POWR

INSPECTION

G630000-0
PISTON PIN AND SMALL END
BEARING

Cleaning

1. Use a soft brush and solvent to clean
the parts.
Inspection
1. Visually inspect for surface defects,
breakage, scratches and pitting. If it is
decided to replace the small end bear-
ings, replace them all.
G63502-0*

CRANKSHAFT

Inspection
1. Place the crankshaft on a crankshaft-
aligner or on V-blocks.
2. Using dial gauge, measure the deflec-
tion.
Maximum deflection:
0.03 mm (0.001 in)
If the deflection is greater than specified
maximum, correct the alignment by use
of a copper hammer and a wedge.
3. Using feeler gauges, measure the con-
necting-rod side clearance.
Connecting-rod side clearance:
0.2 ~ 0.7 mm (0.008 ~ 0.028 in)
If this side clearance exceeds the speci-
fication, replace the crankshaft assem-
bly.
4. Using a dial gauge, measure the con-
necting-rod axial play.
Connecting rod maximum axial
play:
2.0 mm (0.08 in)
If this axial play is greater than the max-
imum axial play, replace the crankshaft
assembly.
5-8
E