Procedure 4.1 - Calibrating The Lift - Precor 9.21 Service Manual

Procedure 4.1 - Calibrating the Lift

WARNING
Always turn off the circuit breaker and unplug the treadmill before you remove the treadmill hood.
Procedure
1. Remove the hood.
2. Remove the lift motor from the treadmill as described in Procedure 6.4 of this appendix.
3. Place the treadmill upright. Lay the motor in front of the treadmill.
4. Plug the lift motor connector into the lower PCA. Connect the lift motor ground to the
treadmill frame.
5. Plug the power cord into the wall outlet, then turn on the treadmill with the circuit breaker.
6. Enter the diagnostics program per procedure 2.1 or 2.2, as appropriate.
If you are servicing a treadmill built before April 1, 1996, use the INCLINE keys to set the
7.
Calibration Number to 20. Set the Calibration Number to 22 if you are servicing a treadmill
built after April 1, 1996.
8. Place 3/8" bolts into the mounting hole on the plastic nut and the top mounting hole of the lift
motor. Place a ruler next to both left or both right edges of the bolts. Turn the plastic nut
without turning the drive screw until the distance between the bolts is 4.00 inches +/- 1/16"
(see Diagram 4.1 ).
Diagram 4.1 - Lift Motor Calibration
±
1/16
4.0
9.21, 9.21i, 9.21S, 9.21Si Treadmill
Drive Screw
Plastic Nut
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