Piston Ring: Service and Repair

TOOL REQUIRED
- J 24086-B Piston Pin Remover/Installer Kit

REMOVAL
1. Compression ring(s) and oil ring from piston using a ring expander.
2. Mount the piston and connecting rod into a Piston Pin Remover/Installer Kit with the arrow mark on the piston head facing up.





3. Piston pin from connecting rod using a Piston Pin Remover/Installer Kit.

CLEAN

TOOLS REQUIRED
- J 3936-03 Piston Ring Groove Cleaner
- J 26900-3 Outside Micrometer
- J 8087 Cylinder Bore Gage


NOTE: Clean carbon from piston ring grooves using a Piston Ring Groove Cleaner and from remainder of piston head using suitable tool.

CAUTION: Inspect piston for cracks or other damage. Replace damaged pistons.

MEASURE





1. Piston diameter at the piston grading position. The piston grading position is located 15 mm (0.59 inch) from the bottom of the piston skirt and perpendicular to the piston pin using a Outside Micrometer. Record measurement.








2. Cylinder bore inside diameter using a Cylinder Bore Gage. Cylinder bore inside diameter limit is 74.15 mm (2.9193 inches). Record measurement.
3. Piston oil clearance by subtracting the piston outside diameter from the cylinder bore inside diameter. If the piston oil clearance is not 0.02 to 0.04 mm (0.0008 to 0.0015 inch) in any cylinder, replace all three pistons. If necessary, rebore all three cylinders or replace the cylinder block. There are three sizes of piston available; one standard and two oversized:
- Original Piston: 73.970 to 73.990 mm (2.9122 to 2.9130 inch)
- 0.25 mm (0.0098 inch) Oversize Piston: 74.220 to 74.230 mm (2.9220 to 2.9224 inch)
- 0.50 mm (0.0197 inch) Oversize Piston: 74.470 to 74.480 mm (2.9319 to 2.9323 inch)