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View Full Version : Pump Motor runs HOT - problem?



windfix
08-06-2008, 03:18 AM
I just put a new AO Smith 1 HP motor on my (old) STA-Rite PE pump. The last one burned out in 10 months. I found that the shaft seal must have leaked, as the motor face was corroded inside and eventually started running really loud. This time I got wise and replaced all o-rings and the shaft seal.

The replaced motor was running really hot - like too hot to leave a finger on more than a second. The new motor runs quiet and is totally functional, but I noticed that it is also super hot within the first hour. Do I have a problem, and any suggestions on diagnosing?

I figure I'll bypass the filter tomorrow and see if it runs cooler - as in bypassing some blockage or the filter is making it work too hard. Another post mentioned a pressure gauge in their system, I don't think I have one aside from on the DE filter though.

JohnT
08-07-2008, 06:34 AM
They normally run hot. Mine is normally around 150F. Not hot enough to burn, but too hot to hold on.

windfix
08-07-2008, 05:14 PM
That is reassuring, thanks! I had a more knowledgeable friend check the voltage on my leads, both are 115 and the motor is set for 230 - so I guess it's wired correctly.

My father's retired electrician friend suggested that the wire gauge should be thicker for the distance from breaker panel - suggested 10 gauge. I am not sure what mine is, but I believe it's 12 (thinner than 10).

I read in another online post that pump motors have an internal thermo sensing shutoff that prevents it from overheating, and that intermittent stop/start symptoms would indicate that switch being tripped. Mine runs continuously, so I think I'll just let it go now and hope for the best.