Quinton TM55, Service Manual

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4-16 Repair/Replacement and Calibration Cardiac Stress Treadmills Service Manual
5. Remove the two hex-head bolts holding the wheels to the rack gears.
Note the arrangement of washers used as spacers.
6. Remove the grade pot and bracket assembly (see step 6, “Replacing
the Grade Potentiometer (Pot) on page 4-14).
7. Rotate the grade pot until a positive number appears in the grade
display window of the stress monitor system. (Step 9 will not work
until the number is positive.)
8. (Requires two people) Decrease grade until rack gears start bouncing
on the pinion shaft. Hold the limit switches closed to let the rack gear
travel beyond its normal range.
9. Turn off and unplug the treadmill.
10. Lift rack gears straight out top.
Reassembling the Rack Gears
Install new rack gears at the same time so that they extend an equal
distance through the headframe.
1. Restore power to the treadmill.
2. Loosen the setscrew that secures the grade potentiometer gear and
remove the gear.
3. Insert rack gears into headframe.
4. Decrease the grade until the gears bounce two or three times, then
increase the grade. This should cause both rack gears to mesh in
exactly the same place.
(step 11)
Rack Gears
3/8-16 x 2.5OL
(step 5)