Piston

Piston Inspection





1. CAUTION: Do not use any aggressive cleaning fluid or a wire brush to clean the piston.

Carry out a visual inspection.
^ Clean the piston skirt, pin bush, ring grooves and crown and check for wear or cracks.
^ If there are signs of wear on the piston skirt, check whether the connecting rod is twisted or bent.

Piston Pin to Bore Diameter





1. NOTE: The piston and piston pin form a matched pair. Do not mix up the components.

Measure the diameter of the piston pin bore.
^ Measure the diameter in two directions.
^ If the values are not to specification, install both a new piston and a new piston pin.

Piston Diameter





1. NOTE: Mark the piston to make sure the piston is installed correctly.

Using a Micrometer measure the piston diameter.

Piston Ring End Gap





1. CAUTION: Do not mix up the piston rings. Install the piston rings in the same position and location.

Take the piston ring and use a piston without rings to push the piston ring about 30 mm into the cylinder bore.





2. Using the Feeler Gauge, measure the piston ring gap.

Piston Ring-to-Groove Clearance





1. NOTE: The piston ring must protrude from the piston groove. To determine the piston ring clearance, insert the Feeler Gauge right to the back of the groove, behind the wear ridge.

Using the Feeler Gauge, measure the piston ring clearance.

Piston Pin Diameter





1. NOTE: The piston and piston pin are a matched pair. Do not mix up the components.

Measure the piston pin diameter.
^ Measure the diameter in two directions.
^ If the values are not to specification, install a new piston and a new piston pin.