Piston Ring Fitting

STANDARD PROCEDURE - PISTON RING FITTING
1. Carefully clean the carbon from all ring grooves. Oil drain openings in the oil ring groove and pin boss must be clear. DO NOT remove metal from the grooves or lands. This will change ring-to-groove clearances and will damage the ring-to-land seating.
2. Be sure the piston ring grooves are free of nicks and burrs.





3. Measure the ring side clearance with a feeler gauge fitted snugly between the ring land and ring (Fig. 42). Rotate the ring in the groove. It must move freely around circumference of the groove.








RING SIDE CLEARANCE CHART





4. Place ring in the cylinder bore and push down with inverted piston to position near lower end of the ring travel. Measure ring gap with a feeler gauge fitting snugly between ring ends (Fig. 43).

RING GAP MEASUREMENT CHART

5. The oil control rings are symmetrical, and can be installed with either side up. It is not necessary to use a tool to install the upper and lower rails. Insert oil rail spacer first, then side rails.





6. Using a ring expander, install compression rings with manufactures designation pointing toward piston crown (Fig. 44).

Ring Gap Orientation





^ Position the gaps on the piston as shown (Fig. 45).
^ Oil spacer Gap on center line of piston skirt.
^ Oil rails gap 180° apart on centerline of piston pin bore.
^ No. 2 Compression ring Gap 120° from top oil rail gap.
^ No. 1 Compression ring Gap 120° from No. 2 compression ring gap.