Piston Ring: Testing and Inspection
INSPECTIONCAUTION: Used piston rings should not be transferred from one piston to another, regardless of mileage or piston ring failure may occur.
- Inspect the piston rings for abnormal wear or damage. Replace if necessary. Replace all rings that are scored, broken, chipped or cracked.
PISTON RING END GAP
1. Insert the piston ring into the cylinder by hand and use the piston to push the piston ring slightly beyond bottom of the piston ring travel area 115 mm (4.5 inches) from cylinder block deck face.
2. Use a feeler gauge to measure the ring opening clearance (end gap).
3. If gap is outside of specifications, use a different ring set.
Top Ring: 0.25-0.41 mm (0.00984-0.01614 inch).
Second Ring: 0.38-0.64 mm (0.01496-0.02520 inch).
Oil Ring: 0.15-0.65 (0.00591-0.02559 inch).
PISTON RING-TO-GROOVE CLEARANCE
NOTE: If lower lands have high steps, piston should be replaced.
1. Check ring-side clearance of compression rings with Feeler Gauge D81L-4201-A or equivalent inserted between ring and its lower land. Gauge should slide freely around entire ring circumference without binding. Any wear that occurs will form a step at inner portion of lower land.
2. If clearance is greater than service limit, replace piston ring.
3. If clearance exceeds service limit, even with a new piston ring, replace piston.
Compression (Both): 0.030-0.080 mm (0.00118-0.00315 inch).
Oil, Maximum: 0.15 mm (0.0006 inch).