1. Cylinder Component Service

1.5. SKILL DRILL 7-2  Measuring Piston-to-Cylinder Wall Clearance

SKILL DRILL 7-2  Measuring Piston-to-Cylinder Wall Clearance

 

STEP 1
Before installing piston rings, insert the inverted piston into a clean and properly honed or prepped cylinder.

STEP 2
Place a feeler blade between the piston and the cylinder wall at 90 degrees to the piston pin bore. Using the largest feeler blade that will slide with a reasonable amount of drag, measure the clearance between the skirt and the cylinder wall Figure 63.

STEP 3
Compare the thickness of the feeler blade with the OEM specifications. Generally, the clearance is ideally 0.0035" (0.0889 mm) between the piston and the cylinder wall. This clearance allows for just an adequate film of lubricating oil Figure 62.

 

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