Piston Selection
WARNING: This page is about a different car, the 2002 GMC Savana and 2002 Chevrolet Chevy Express. However, it is still accessible from the selected car via links, so may be relevant.
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 piston pin set may be reinstalled if, after cleaning and inspection, the piston and piston pin are within specifications.
- 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 and 90 degrees to the crankshaft centerline.
- Measure the J 8087 with a micrometer and record the reading.
- With a micrometer or caliper at a right angle to the piston pin bore, measure the piston 11 mm (0.433 in) from the bottom of the skirt.
- Subtract the piston diameter from the cylinder bore diameter in order to determine piston-to-bore clearance. Refer to Engine Mechanical Specifications .
- 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.
- When the piston-to-cylinder bore clearance is within specifications, permanently mark the top of the piston for installation into the proper cylinder.