To check a flywheel face runout, where should the dial indicator be positioned?

Positioning the dial indicator at the base of the bell housing with the pointer on the flywheel face is the correct method to check a flywheel face runout. This setup allows for accurate measurement of the runout by ensuring that the indicator is measuring the deviation of the flywheel’s surface relative to a fixed, stable point—the bell housing. This positioning effectively captures any eccentricity or distortion in the flywheel that may affect its performance during operation.

Choosing this method is critical because a flywheel that is not properly aligned can lead to significant issues, including increased vibration and potential damage to the engine components over time. The bell housing serves as a reliable reference point as it is securely mounted and free from movement, making the readings obtained from the dial indicator more consistent and reliable.

The other options would not provide an accurate assessment of runout: checking at the center of the flywheel may miss variations along its surface, measuring on the crankshaft would not directly reflect the flywheel's condition, and placing the indicator near the engine block could introduce inaccuracies due to alignment differences and clearance issues.