Check end clearance of piston rings

Prerequisite 

Cylinder path is cleaned. Cylinder was measured and is within the permissible tolerances.

Position the piston ring in the cylinder 

• Position the piston ring (1) in the cylinder path below the TDC.

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Insert the piston ring end clearance in the cylinder 

• Insert the piston ring (1) into the cylinder to be measured and rotate by 90°.

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Position the piston ring with the piston in the cylinder 

• Use the piston (1) to push the piston ring in parallel to the last annular groove (see graphic).

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End clearance on the piston ring 

• Gap at the piston ring 1 (refer to graphic).

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Check 

• Insert upper piston ring into the cylinder and slide to TDC with the pistons.
• Check the end clearance of the upper piston ring with a feeler gauge.

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End clearance of upper piston ring
Before measuring the end clearance, make sure the cylinder is within the permissible tolerance.	0.15 mm... 0.25 mm

Result 

» End clearance is outside tolerance.

Measure 

• Replace upper piston ring.

Check 

• Take upper piston ring out of the cylinder.
• Insert center piston ring into the cylinder and slide to TDC with the pistons.
• Check the end clearance of the center piston ring with a feeler gauge.

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End clearance of center piston ring
Before measuring the end clearance, make sure the cylinder is within the permissible tolerance.	0.30 mm... 0.45 mm

Result 

» End clearance is outside tolerance.

Measure 

• Replace center piston ring.