help, motor problem

Of course it has no brushes, since it?s an asynchronous motor.The capacitor is used for creating a rotating magnetic field inside the stator, by means of the single phase current that?s supplied to the machine.Actually, AFAIK these pumps are so cheap that you shouldn?t even thin of repairing it.

-- Dimitris Tzortzakakis,Greece

Ï Wayne Kerr Ýãñáøå óôï ìÞíõìá óõæÞôçóçò: 3fc063cf$0$113$ snipped-for-privacy@mercury.nildram.net...

Sounds like a single-phase AC motor. Given your symptoms, I'd look at the centrifugal switch used to cut the start winding/capacitor out when the motor comes up to speed. If it doesn't reclose when the motor stops, the motor won't re-start (unless you kick it or jar it in someway to get the switch contacts to close again).

daestrom

If the centrifugal switch was not closed upon starting, the motor would just hum and not turn. Turning the shaft one way or the other would start the motor turning and would come up to speed on the run windings. If this is the case, take a look at the switch and see if there are pits in the contacts that keep it from closing, or maybe it is just burned up.

You could test the capacitor by getting a multimeter and selecting the ohms tester, then putting it across the cap, it should appear as a dead short then rapidly fall towards an open circuit as it charges.

I doubt you pump is a cap-start run motor with a centrifigal switch, its more likely a permanent-split cap motor, These by design have a low starting torque, so maybe the bearings are flogged out in the motor or a bit of crap is jamming it somewere.

As for a replacement cap, see if you can scavenge one off a discarded appliance or something, The value isn't overly critical, just make sure its rated at the correct voltage.