BRP Johnson J30TEL4SUA 2007 Service Manual page 143

IMPORTANT:
The journal are numbered are in
order from the flywheel magnet to the bottom of
the cylinder.
Camshaft Journal Outside Diameter
Journal
No. Standard
1.7096 – 1.7106 in.
Top
(
43.425 – 43.450 mm
1.7175 – 1.7185 in.
2nd
(
43.625 – 43.650 mm
1.7254 – 1.7264 in.
3rd
(
43.825 – 43.850 mm
1.7333 – 1.7343 in.
4th
(
44.025 – 44.050 mm
Camshaft Journal Bore Inside Diameter
Journal
No. Standard
1.7126 – 1.7136 in.
Top
(
43.500 – 43.525 mm
1.7205 – 1.7215 in.
2nd
(
43.700 – 43.725 mm
1.7283 – 1.7293 in.
3rd
(
43.900 – 43.925 mm
1.7362 – 1.7372 in.
4th
(
44.100 – 44.125 mm
Subtract the camshaft journal outside diameter
measurement from the camshaft journal bore
inside diameter measurement to determine the
journal oil clearance.
If the camshaft journal oil clearance exceeds the
service limit, replace the camshaft and/or the cyl-
inder head.
Camshaft Journal Oil Clearance
Standard
0.002 – 0.004 in.
Service Limit
Rocker Arm and Shaft
Inspect each rocker arm. If the tip of the adjusting
screw is excessively worn, replace the screw. If
Service Limit
1.7077 in.
) ( )
43.375 mm
1.7156 in.
) ( )
43.575 mm
1.7234 in.
) ( )
43.775 mm
1.7313 in.
) ( )
43.975 mm
Service Limit
1.7139 in.
) ( )
43.534 mm
1.7218 in.
) ( )
43.734 mm
1.7300 in.
) ( )
43.934 mm
1.7376 in.
) ( )
44.134 mm
(
0.05 – 0.10 mm
( )
0.006 in. 0.16 mm
the cam riding face is excessively worn, replace
the rocker arm.
1. Adjusting screw
2. Cam riding face
Use a set of "V" blocks to support the rocker arm
shaft on a surface plate. Use a dial gauge to mea-
sure the shaft runout.
The service limit for rocker arm shaft runout is
0.005 in. (0.12 mm). If the measurement exceeds
this specification, replace the shaft.
2
1. Dial gauge
2. Rocker arm shaft
Use a micrometer and a bore gauge to measure
)
the rocker arm shaft outside diameter and the
rocker arm bore inside diameter.
Rocker Arm and Shaft Specifications
Rocker Arm Shaft
Outside Diameter
Rocker Arm Bore
Inside Diameter
Subtract the rocker arm shaft outside diameter
from the rocker arm bore inside diameter to deter-
mine the rocker arm-to-shaft clearance.
POWERHEAD
CYLINDER HEAD
2
1
001481
1
001482
0.6289 – 0.6294 in.
(15.973 – 15.988 mm)
0.6299 – 0.6306 in.
(16.000 – 16.018 mm)
141
7