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Home >> Chevrolet >> 2020 >> Express 2500 LS, 6.0L Eng VIN G >> Repair and Diagnosis >> External Pages >> Different car >> Section 3 (Engine Mechanical - 4.3L (LV1)) >> Repair Instructions - Off Vehicle >> Piston, Connecting Rod, and Bearing Installation >> Piston Selection

Piston Selection

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  1. GM1552496Courtesy of GENERAL MOTORS COMPANY
    NOTE:

    Measurements of all components should be taken with the components at normal room temperature. For proper piston fit, the engine block cylinder bores must not have excessive wear or taper. A used piston, pin, and connecting rod assembly may be installed if, after inspection is within specifications.

    With a micrometer at a right angle, measure the piston outside diameter (OD). Measure the diameter 43 mm (1.69 in) from the top of the piston. Refer to Engine Mechanical Specifications (LV1) .

  2. Record the piston OD.
  3. GM4974Courtesy of GENERAL MOTORS COMPANY

    Adjust the micrometer to the recorded piston OD.

  4. Insert the EN - 8087  bore gauge into the micrometer and zero the gauge dial.
  5. GM4972Courtesy of GENERAL MOTORS COMPANY

    Using the EN - 8087  bore gauge, measure the cylinder bore inside diameter (ID). Measure at a point 64 mm (2.5 in) from the top of the cylinder.

  6. Record the cylinder bore ID.
  7. Subtract the piston OD from the cylinder bore ID in order to determine the piston-to-bore clearance. Refer to Engine Mechanical Specifications (LV1) .
  8. If the proper clearance cannot be obtained, select another piston and pin assembly and measure the clearances again. If the proper fit cannot be obtained, the cylinder bore may require honing for an oversize piston.