Piston Ring: Testing and Inspection

1. Using a suitable feeler gauge, measure the clearance between new piston ring and the wall of the ring groove.
Ring groove clearance: No. 1 and No. 2: 0.020-0.060 mm (0.0008-0.0024 inch).
If the clearance is not as specified, replace the piston.
2. Inspect piston ring end gap as follows:
(a) Insert the piston ring into the cylinder bore.





(b) Using a piston, push the piston ring a little beyond the bottom of the ring travel, 105.000 mm (4.1300 inch) from the top of the cylinder block.





(c) Using a suitable feeler gauge, measure the end gap as shown.
Standard end gap:
No. 1: 0.250-0.450 mm (0.0098- 0.0177 inch).
No. 2: 0.350-0.500 mm (0.0138-0.0197 inch).
Oil (Side rail): 0.150-0.550 mm (0.0059-0.0217 inch).
Maximum end gap:
No. 1: 1.050 mm (0.0413 inch).
No. 2: 1.100 mm (0.0433 inch).
Oil (Side rail): 1.150 mm (0.0453 inch).
3. If the end gap is greater than maximum, replace the piston ring.
4. If the end gap is greater than maximum, even with a new piston ring, replace the cylinder block.





5. Inspect piston pin fit, at 60° C (140° F), you should be able to push the piston pin into the piston pin hole with your thumb.