Piston ring side clearance
Measure backlash between piston ring and piston groove using a set of flat feeler gauges (A).
If the measured value exceeds the limit value, replace the piston ring and repeat the measurement. If the value is still n.d., replace the piston as well.
Piston ring gap
Lubricate the piston (1) and piston ring (2) fresh engine oil, then use the piston to push the piston ring (A) to the middle of the cylinder (IN), and measure the clearance and lock of the piston ring with a flat feeler gauge (WITH).
If the measured value exceeds the limit value, replace the piston ring and measure again.