Short in pump motor...where?

[kjcole]

4 year old Sta-Rite JWPA pump with A.O. Smith motor, wired directly to timer output on my chlorine generator control panel. 2 nights ago finally got rain. Circuit breaker (GFIC) for pump tripped when timer turned it on in morning. Isolated short circuit to motor. Took motor apart, looked for obvious shorts from loose or bare wires. Nothing. Poked around, put it back together plugged it in (120 v) and it ran. Reinstalled everything and pump ran all day and turned on again in morning. Noticed shaft seal leak (salt water pool, also) so I ordered shaft-seal kit. Last night, rain. GFIC tripped again in the morning. This time can't resolve the short. What shorts out on these motors? Windings? Looks like some kind of centrifugal set-up on the shaft (white thing bridged by a spring. Also some breaker points running to a capacitor? I'm ready to order a new motor, just curious about these things, since the motor isn't very old.

Thanks, in advance for any insights.

Kelly

 

[JasonLion]

A GFCI can trigger when there is moisture bridging two contacts, whiteout any conventional short. You said both problems were right after rain, so I am thinking that water is getting into an electrical box, or the pump, when it shouldn't be.

 

[kjcole]

Right now pump/motor are sitting on my bench. Circuit breaker trips instantly when I plug the motor in. Everything sure looks dry in the motor now. Maybe I'll hit the windings with compressed air again and let it dry completely overnight.

Motor/pump have been located under my deck on a cement pad, somewhat protected, working flawlessly for 3 1/2 years. Wondering if I'm seeing effects of corrosion coupled with the extra moisture from rain. Thinking I'm ordering a new motor.

 

[kjcole]

Motor and pump sat on bench overnight. Blew compressed air through windings etc. Plugged it in this morning and started right up. Reinstalled and pumping right now. Ordering a new motor in anticipation of the next rain! $133 with free shipping - can't complain about that.