Tools Required

J 8087 Cylinder Bore Gauge

Important: Measurements of all components should be taken with the components at normal room temperature.

For proper piston fit, the engine block cylinder bores should not have excessive wear or taper.
A used piston and pin set may be reinstalled if, after cleaning and inspection, the piston and pin set are within specifications.
1. Use the J 8087 in order to measure the cylinder bore diameter. Measure at a point 64 mm (2.5 in) from the top of the cylinder bore.



2. Measure the J 8087 with a micrometer and record the reading.



3. With a micrometer or caliper at a right angle to the piston, measure the piston 11 mm (0.433 in) from the bottom of the skirt.
4. Subtract the piston diameter measurement from the cylinder bore diameter measurement in order to determine piston-to-bore clearance.

Specification
Piston-to-bore clearance 0.018-0.068 mm (0.0007-0.0026 in).

5. If the proper clearance cannot be obtained, then select another piston and measure the clearances.

If the proper fit cannot be obtained, the cylinder bore may require honing or boring.

6. When the piston-to-cylinder bore clearance is within specifications, permanently mark the top of the piston for installation into the proper cylinder.