Cylinder Bore Out-of-Round

WARNING: This page is about a different car, the 2012 Ford Pickup, 2012 Ford F550 Super Duty, 2012 Ford F450 Super Duty, and 2012 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Typical cylinder block shown.

Fig 1: Measuring Bore Gauge Reading Coincides With Center Line Of Crankshaft

Courtesy of FORD MOTOR CO.

Use a cylinder bore gauge to check the cylinder bore for out-of-round conditions.
- Measure the diameter of the cylinder bore at the top of piston travel. Be sure to measure at a right angle to the center line of the crankshaft. Record the reading as dimension A.
- Measure the bore so that the gauge reading coincides with the center line of the crankshaft. Record the reading as dimension B.
- The difference between dimension A and dimension B is the out-of-round condition at the top of the cylinder bore. For additional information, refer to Specifications .
Repeat the same procedure at the bottom of the ring travel to check for out-of-round conditions.