Cylinder Bore Taper and Out-of-Round

^ Tools Required
- J 8087 Cylinder Bore Gauge, Or equivalents

NOTE:
^ If or more of the cylinder bores are rough, scored, or worn beyond limits, smooth or true up the damaged bores in order to fit new pistons.
^ Do not cut down oversize pistons in order to fit the cylinder bores, as this will destroy the surface treatment and affect the weight. Use the smallest possible oversize service pistons and hone the, cylinder bores to size for the proper clearances.

1. Ensure that the cylinder bore tolerances are correct.
2. Depress the plunger on the tool 7 mm (0.03 inch) or until the tool enters the cylinder bore.
3. Center the gauge in the cylinder. Turn the dial to zero.
4. Carefully work the gauge up and down the cylinder in order to determine the taper and turn it to different points around the cylinder wall to determine the out-of-round condition.
5. Measure the bore both parallel to and at right angles to the engine centerline. Measure at the top, middle, and the bottom of the bore and note the readings.