Step 1
Listen for excessive noise. This could be indicative of worn bearings or a lack of lubrication. Have the rotor assembly replaced if it is the former, whereas add lubricating oil to the gears and gear posts for the latter problem.
Step 2
Check the supply voltage circuit and reset any breakers if necessary if your motor does not run and your fan doesn't turn. If there appears to be no problem with the power, then you should check for a damaged power cord or faulty wire connections; both problems will require the faulty parts to be replaced.
Step 3
Ensure the voltage and frequency matches the listing on the data label if the motor is overheating and shutting off. This can often indicate and incorrect voltage and should be remedied by following the instruction on the data label.
Step 4
Turn over or replace the index plate if the pump head does not rotate; it is often due to a worn index plate. You should also consider replacing the roller assembly, as a stripped pump head roller assembly can often be to blame.