Measuring Piston Rings
To get an accurate gap reading, always measure the rings three times:
Take off the cylinders. Measure the space between the edge of the ring and the edge of the ring groove in the piston. check the manual for the maximum allowable space.
Take the rings off the pistons. Don't mix them up. Put them evenly into the bottom of their cylinder - push then in with the top of the piston. Measure the end gap. It wants to be pretty close to what the manual says. If you don't have a manual - about .001" - .002" gap Per Inch of piston diameter.
Then slide them up to the top of the bore - say: 1" down. Measure again. A big increase in end gap between top and bottom indicates cylinder wear.
The pistons want to be pretty secure in their bores too. If you can move them back and forth (with your fingertips) more than very slightly - they are worn out.
Take off the cylinders. Measure the space between the edge of the ring and the edge of the ring groove in the piston. check the manual for the maximum allowable space.
Take the rings off the pistons. Don't mix them up. Put them evenly into the bottom of their cylinder - push then in with the top of the piston. Measure the end gap. It wants to be pretty close to what the manual says. If you don't have a manual - about .001" - .002" gap Per Inch of piston diameter.
Then slide them up to the top of the bore - say: 1" down. Measure again. A big increase in end gap between top and bottom indicates cylinder wear.
The pistons want to be pretty secure in their bores too. If you can move them back and forth (with your fingertips) more than very slightly - they are worn out.
PHM - USA
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