BRP Johnson J30TEL4SUA 2007 Service Manual page 158

POWERHEAD
PISTON, CYLINDER, AND CRANKSHAFT
Wrist Pin and Bores
Inspect the wrist pin and the bores in the piston
and the connecting rod for wear and damage.
Use a micrometer to check the wrist pin outside
diameter.
If the measurement exceeds the service limit,
replace the wrist pin.
Wrist Pin Outside Diameter
Standard
Service Limit 0.6291 in. (15.980 mm)
1
1. Wrist pin
Use dial calipers to measure the piston bore
inside diameter.
If the measurement exceeds the service limit,
replace the piston assembly.
Piston Bore Inside Diameter
Standard
Service Limit
1
1. Piston bore
156
0.6297 to 0.6299 in.
(15.995 to 16.000 mm)
0.6302 to 0.6305 in.
(16.006 to 16.014 mm)
0.6311 in. (16.030 mm)
Use dial calipers to measure the connecting rod
small bore inside diameter.
If the measurement exceeds the service limit,
replace the connecting rod.
Connecting Rod Small Bore Inside Diameter
Standard
1
1. Connecting rod small bore
To check the wrist pin-to-piston bore clearance,
subtract the wrist pin outside diameter from the
piston bore inside diameter. To check the wrist
pin-to-connecting rod small bore clearance, sub-
001554
tract the wrist pin outside diameter from the con-
necting rod small bore inside diameter.
If either measurement exceeds the service limit,
replace the wrist pin or the piston assembly.
Wrist Pin-to-Piston Bore Clearance
Standard
Service Limit
Wrist Pin-to-Connecting Rod
Standard
Service Limit
001555
0.6300 to 0.6304 in.
(16.003 to 16.011 mm)
0.0002 to 0.0007 in.
(0.006 to 0.019 mm)
0.0016 in. (0.040 mm)
Small Bore Clearance
0.0001 to 0.0006 in.
(0.003 to 0.016 mm)
0.0020 in. (0.050 mm)
001556