BRP Johnson J30TEL4SUA 2007 Service Manual page 156

POWERHEAD
PISTON, CYLINDER, AND CRANKSHAFT
Pistons and Rings
Two oversize piston and piston ring components
are available. Oversize pistons and piston rings
are marked as shown below.
Piston
Oversize
0.25 mm
0.50 mm
1. ID mark – piston
Top and Second Compression Rings
Oversize
0.25 mm
0.50 mm
1. ID mark – top and second compression rings
154
ID Mark
0.25
0.50
1
001548
ID Mark
25
50
1
001549
Oil Ring
Oversize
0.25 mm
0.50 mm
1
1. ID mark - oil ring
Inspect the pistons for faults, cracks, and other
damage. Replace any damaged pistons.
Inspect the piston ring grooves. Remove any car-
bon deposits. Clean and dry the piston thoroughly.
Fit the compression ring into the groove. Use a
thickness gauge to measure the clearance
between the ring and the groove.
ID Mark
Two blue marks
Red mark
001550