Piston: Testing and Inspection

TOOL REQUIRED
- J 26900-3 Outside Micrometer
- J 8087 Cylinder Bore Gage

MEASURE





1. Piston diameter at the piston grading position using a Outside Micrometer. The piston grading position is located 15 mm (0.59 inch) from the bottom of the piston skirt and perpendicular to the piston pin. 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 engine oil clearance by subtracting the piston outside diameter from the cylinder bore inside diameter. If the piston engine oil clearance is not 0.02 to 0.04 mm (0.0008 to 0.0015 inch) in any cylinder, replace all four pistons. If necessary, rebore all four 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 (2.9920 to 2.9224 inch)
- 0.50 mm (0.0197 inch) Oversize Piston: 74.470 to 74.480 mm (2.9319 to 2.9323 inch)