BRP Johnson J30TEL4SUA 2007 Service Manual page 157

If the measurement exceeds the service limit,
replace the piston and/or the piston rings.
Piston Ring-to-Groove Clearance
Top
Standard
2nd
Top
Service Limit
2nd
Piston Ring Groove Width
Top compression ring
2nd compression ring
Oil ring
Piston Ring Thickness
Top compression ring
2nd compression ring
Insert the piston ring into the lowest position of the
cylinder bore. Use a thickness gauge to measure
the piston ring end gap.
0.0012 to 0.0027 in.
(0.03 to 0.07 mm)
0.0008 to 0.0024 in.
(0.02 to 0.06 mm)
0.005 in. (0.12 mm)
0.004 in. (0.10 mm)
001551
0.0400 to 0.0410 in.
(1.02 to 1.04 mm)
0.0476 to 0.0484 in.
(1.21 to 1.23 mm)
0.0790 to 0.0800 in.
(2.01 to 2.03 mm)
0.038 to 0.039 in.
(0.97 to 0.99 mm)
0.046 to 0.047 in.
(1.17 to 1.19 mm)
PISTON, CYLINDER, AND CRANKSHAFT
If the measurement exceeds the service limit,
replace the piston rings.
Piston Ring End Gap
Top
Standard
2nd
Top
Service Limit
2nd
3
1
1. Cylinder
2. Piston ring
3. Thickness gauge
Use vernier calipers to measure the piston ring
free end gap.
If the measurement exceeds the service limit,
replace the piston rings.
Piston Ring Free End Gap
Top
Standard
2nd
Top
Service Limit
2nd
POWERHEAD
0.005 to 0.011 in.
(0.12 to 0.27 mm)
0.014 to 0.020 in.
(0.35 to 0.50 mm)
0.028 in. (0.70 mm)
0.039 in. (1.00 mm)
2
001552
0.36 in. (9.1 mm)
0.35 in. (9.0 mm)
0.29 in. (7.3 mm)
0.28 in. (7.2 mm)
001553
155
7