Stairmaster 4000 PT series, Owner'S Manual

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Page 42
MECHANICAL TROUBLESHOOTING
If you hear a grinding or clicking noise, experience excessive vibration during
exercise, or if the pedals are not functioning properly, you probably have a
problem in the drive train. Attempt to isolate the problem area by performing
the following tests in precisely the order listed below.
1. Unplug the machine and remove the bottom side covers.
2. Noise can be generated by a Poly-V belt that is either too tight
or too loose. Check the condition and the tension of the belt.
Replace a worn belts. Adjust the belt tension according to the
instructions in the "Parts Removal and Replacement" section.
3. Remove the Poly-V belt and move the pedal arms. If the noise no
longer exists, check the condition of the alternator. If the noise is still
present, go to step #4. Do not reinstall the Poly-V belt if performing
step #4.
• Disconnect the DC power cable. Spin the alternator pulley with
your fingers. It should spin freely and remain spinning for at least
two revolutions. If it does not, the alternator should be replaced.
• If the alternator does spin freely, check the alternator for noise,
roughness, or the presence of an excessive amount of black
powder inside the alternator or near the outside of the case. If
any of these conditions exist, the brushes might be bad.
Replacement brushes are available as well as replacement
alternators.
4. Tighten the transmission pulley set screw onto the flat side of the
transmission output shaft. Tighten the transmission drive sprocket set
screw to the keyway in the transmission input shaft.
TO REDUCE THE RISK OF INJURY, DO NOT OPERATE THE MACHINE
WHILE THE COVERS ARE REMOVED. DO NOT DEPRESS OR RAISE THE PEDALS WHILE
ANYONE'S HANDS ARE INSIDE THE MACHINE.
!
WARNING