Pump motor overheats in about 30 seconds

Jump to latest Follow Reply
T

touchton

0
Apr 19, 2011
13
Our pool is almost 2 years old and everything was working fine yesterday. This morning I notice the water is not moving at a time when the pump is scheduled to be on. At the control panel the breaker for the pump motor was tripped. I reset the breaker and the motor turned on for about 30 seconds and shut off. The motor sounded strained to me, but that's subjective. Apparently, it's the thermal overload that's shutting the motor off. Once it cools, I can run it again for about 30 seconds.

I've checked the voltage and amperage to the motor. It's on a 240VAC circuit. The voltage is fine, the amperage is high. But, that's to be expected at this point.

I looked at the pressure in the filter when the pump was running and it's about half of what it normally runs.

So, to me, it appears I either have a defective motor, or something is wrong with the pump that's putting a large strain on the motor. I'm actually leaning more toward the pump. How can I determine the cause? What I have is a Hayward TriStar Pump Series. Is it logical to just mechanically separate the two and run the motor with no load?

I'm about to head out to a Titan's game so I won't have time to work on this until later this afternoon. I appreciate any assistance you can offer.

Thanks.
Thad
 
Sounds like it is either the bearings or an obstruction in the wet end. One way to tell if it is the bearing to rotate the motor shaft by and and see if the rotation is restricted in any way. But you may want to separate the wet end and motor to inspect both for issues.
 
Thanks Mark. I'm in the process of separating the motor from the pump now. After a bit of difficulty, I have the four bolts removed. One must have had red Loctite on it....... At this point I would think I could pull the motor away from the pump, but it appears stuck. I'll get a rubber mallet and tap on it for awhile to separate the two.

Should I be able to turn the motor shaft easily? I would think if it was a bearing, I would have heard a loud screeching sound when the motor runs. And, should I be able to turn the pump easily too?

Thanks.
Thad
 
macgulley said:
My money is on you finding something that got through the strainer and is binding up the impeller.
Click to expand...
I hope so. I was going about removing the motor incorrectly. I didn't realize I needed to pull the back plate of the pump off with the motor. I'll work more on it this afternoon.

Thad
 
I pulled the pump apart and really didn't find anything to speak of. Once I got to the impeller, it did not turn freely and seemed to grind. There appears to be some wear on the inside of the impeller ring and wear on it's mating surface of the impeller. The shaft seal was really nasty. I cleaned it and the shaft, put everything back together and the impeller turns much better, and quiet now. I'm not sure how easy it's supposed to turn. If it give it a spin, it does continue turning when I let go. Not for long, but it does turn much easier.

So, I go to put the motor/pump back into the strainer basket assembly and I bump the wall with the back of the motor. I broke the plastic switch mount that has the contacts for the capacitor. Now I can't test it because of a 25 cent part (I'm sure it'll cost me $10 once I find one).

I have some pictures of the wear on the impeller and impeller ring I'll try to post. I need to go grab dinner now.......

Thad
 
Here's the pictures. First, the impeller wear. I would think this should be smooth, but there are grooves parallel with the impeller movement.
Impellerwear.jpg


Here's the impeller ring with the same type of wear.
Impellerringwear.jpg


The motor shaft nastiness.
MotorShaft.jpg


And, here's what I broke in the process.
BrokenSwitchBracket.jpg
 
What is that stuff that is covering the entire internal pump body?

Looks like calcification and will make resealing that pump very difficult and perhaps impede the efficiency of the pump. If that's what it is, I would consider a new pump and find out why you are calcifying up like that and solve that chemistry issue, too.
 

Enjoying this content?

Support TFP with a donation.

Give Support
You should expect some wear on the impeller and impeller ring. Neither looks all that bad but it is hard to tell since the pics are out of focus. But looking at the motor, the shaft looks pretty rusted which means the seal had probably failed and was leaking which probably indicates rusted bearings as well.

If the rest of the wet end looks ok, then you probably just need a new motor.
 
It's defiantly looking like a motor now. I glued the starter cap switch back together and assembled everything to give it a try. Same issue where it runs for maybe 30 seconds and shuts off. I can restart it after 5 minutes or so and it does the same thing.

I measured the motor windings and each phase is open to ground and phase to phase is 1.9 to 2.0 ohms. I'm not sure what is should be though. I'm thinking there's a short in the windings somewhere.

Where's a reliable place to buy just the motor? I'll probably replace the motor shaft seal as well. I see them available from Amazon.

Thanks for all the help.

Thad
 
touchton said:
I measured the motor windings and each phase is open to ground and phase to phase is 1.9 to 2.0 ohms. I'm not sure what is should be though. I'm thinking there's a short in the windings somewhere.
Click to expand...
That's normal so the winding's are probably ok.

You can also check the capacitor. Remove the terminals, short the leads and then measure resistance. It starts very low and climes to infinite. But my guess is that the problem lies with the bearings.
 
As long as you can get the exact new one (i.e. mounting face, shaft style, HP, SF, Voltage, etc), an online purchase could save you money over a local pool store. I often buy online, but I know exactly my specifications. I can save over $100 even when you consider shipping costs. I've never received a bad new motor, even when the stock was old. You could loose all your savings if there is a warranty issue, so you need to evaluate the risks. Obtaining a seal online should not be a big deal. I also do that. Know your seal part# or style number, because there are a few different types.

BTW, you might be shocked at what that starting switch costs.
 
You must log in or register to reply here.
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.
Top Bottom
Back
Jump to latest Follow Reply