Runout

With the coupling disconnected, mount the
magnetic base of the dial indicator to the motor
half coupling, position the indicator on the pump
half coupling and center the indicator plunger.

Rotate the pump shaft until the dial indicator
reaches a maximum travel, then zero the dial indicator.
Rotate the pump shaft again until the dial
indicator reaches a maximum value. This shows the
amount of runout.

If the runout on the pump side is in excess of
the acceptable limit of 0.002”, the pump shaft runout
should be checked as above, except with the dial
indicator applied to the shaft. If the shaft runout is
0.001” or less, the shaft can be considered acceptable,
but the coupling is eccentric. If, however, the
shaft runout is greater than 0.001”, the shaft should
be straightened. By switching the position of the
dial indicator, the driver shaft can be checked in the
same manner with the same limitations.