Quinton TM55, Service Manual

Page: 43 / 82

Cardiac Stress Treadmills Service Manual Repair/Replacement and Calibration 4-19
2. Restore power to the treadmill, then use the grade motor to turn the
pinion shaft until the setscrew on the sprocket is visible.
3. Turn off the power and the treadmill circuit breaker, then unplug the
treadmill.
4. Loosen the setscrews from the grade sprocket.
5. Remove the grade motor chain as described on page 4-13.
6. Remove the handrail support bracket on the right side.
7. Slide out the pinion shaft.
8. Slide the new pinion shaft into place: be sure to reinstall the grade
sprocket and key while installing the pinion shaft.
9. Replace the handrail support bracket.
10. Use a straight edge to align the grade sprocket and grade motor
sprocket, then tighten the setscrew.
11. Replace the grade motor chain as previously described.
12. Reassemble the deck assembly and poly-V drive belt.
13. Reassemble the rack gear.
14. Calibrate the grade potentiometer (see “Calibration Procedures” on
page 4-26).
15. Test the treadmill grade. Verify that:
a. it operates over the full range of 0-25%.
b. there is no binding when it moves up or down.
c. the grade motor chain is aligned correctly. A popping sound in the
chain indicates misalignment.
16. Unplug the treadmill. If no other service is required, replace the
treadmill hood as described in step 9 on page 4-3.
17. Replace the side bumpers.
Grade Motor
Chain
Pinion Shaft