Piston Ring: Service and Repair

PISTON RING FITTING






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

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

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

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





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

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

NOTE: Make sure marks on compression rings face upward.

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





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





9. Install No. 2 intermediate piston ring using a piston ring installer.
10. Install No. 1 upper piston ring using a piston ring installer.





11. Install the oil ring expander gap at the (5) position.
12. Install the oil ring lower side rail gap at the (4) position.
13. Install the oil ring upper side rail gap at the (1) position.
14. Install the second compression ring gap at the (5) position.
15. Install the top compression ring gap at the (2) position.