Piston Ring: Service and Repair

STANDARD PROCEDURE - PISTON RING FITTING





CAUTION: Before reinstalling used piston rings or installing new piston rings, the piston ring clearances must be checked or engine damage may result.

1. Wipe the cylinder bore clean.
2. Insert the piston ring into the cylinder bore.

NOTE: The piston ring gap measurement must be made with the piston ring positioned at least 12 mm (0.50 inch) from bottom of cylinder bore.

3. Using a piston, make sure that the piston ring is squared in the cylinder bore. Slide the piston ring downward into the cylinder.
4. Using a feeler gauge (1), check the piston ring end gap, replace any rings not within specification.

PISTON RING SIDE CLEARANCE





NOTE: Make sure the piston ring grooves are clean and free of nicks and burrs.

1. Measure the piston ring side clearance with a feeler gauge (1) as shown. Make sure the feeler gauge fits snugly between the piston ring land and the piston ring, replace any ring not within specification.

NOTE: Make sure the marks on the compression rings face upward.

2. Rotate the ring around the piston. The ring must rotate in the groove with out binding.

PISTON RING INSTALLATION





1. Install the oil ring expander.
2. Install the lower side rail by placing one end between the piston ring groove and the expander ring (1). Hold the lower side rail end firmly and press down the portion to be installed until the side rail is in position. Repeat this step for the upper side rail.





3. Using a piston ring installer, install the No. 2 intermediate piston ring.
4. Using a piston ring installer, install the No. 1 upper piston ring.





5. Install the oil ring expander gap at the (5) position.
6. Install the oil ring lower side rail gap at the (4) position.
7. Install the oil ring upper side rail gap at the (1) position.
8. Install the second compression ring gap at the (5) position.
9. Install the top compression ring gap at the (2) position.