How To Troubleshoot a Pool Pump Motor - Motor Shuts Down


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If your pool pump motor starts but shuts down unexpectedly it is probably overloaded and the thermal overload protection device has tripped. This guide discusses what to look for to correct this issue.

Please click here to view our pool motor troubleshooting guide 

Step by Step


Step 1

CHECK VOLTAGE - Measure the voltage level to the motor terminal. It should be within 10 percent of the voltage listed on the motor label. If it is too high call the local Power Company. This picture shows measuring the voltage across the two output lines to the pump.

Please click here to view our digital multimeter 

Step 2

CHECK AMPERAGE - Measure the amperage to the motor terminal. If high, find out if the pump impeller was recently replaced (it could be sized incorrectly). Remember, motor horsepower times the service factor = total horsepower. Total horsepower must be equal to or greater than the impeller rating. If the impeller is too large for the motor, it will be trying to push more water than the motor can handle and the motor will overload, get hot, and shut down.


(41 to 80 of 101)

InyoPools Product Specialist  Posted: 5/29/2017 

Smoked - Check the gauge of wire between your pump and the circuit breaker. If you have a long run, you may have to go up a gauge of two. If that's good, you may have to invest in a new motor.

 Posted: 5/27/2017 

We have an Hayward SP1580X15 Power-Flo LX 1.5hp pump. When I go to backwash the filter pump shuts down. I replaced the pump thinking it was bad. The new one is doing the same thing. We have a sand filter and no pressure gage. Any idea's as to what could be the problem?

 Posted: 5/26/2017 

I have a 1.0 HP Hayward Superpump that's about 5 years old or so. Recently, it got hot and shut down. It's plugged into a GFCI, which was blackened around the plug. The wiring inside the junction box at the pump got hot enough to melt one of the wire nuts in half, causing it to fall off. I cut the wire back and re-wired the pump. It clicked a few times and then was silent. Is it fixable or is it more cost effective to replace the pump motor?

InyoPools Product Specialist  Posted: 5/3/2017 

JR - If you replaced the impeller recently, I would concentrate on that. Make sure you have the correct replacement impeller. It has to match the total HP calculated for your motor, not the HP. Total HP rating is calculated by multiplying the listed HP on the motor label with the motor's Service Factor (SF). If the impeller is a size larger than the original, it will require greater torque than the motor can deliver and overheat quickly. Also, check that the new shaft seal was seated correctly. If it is not on straight, it will add friction to the rotating motor and cause it to overheat.

 Posted: 5/2/2017 

Have a Century AO Smith B849 that was replaced about 3 years ago, and the impeller was replaced just a couple months ago. Pool ran fine for a while then recently it started doing a start loop. It tries to start up, I can immediately see water moving in the clear top pump filter basket, but then stops within a few seconds. Then it tries again in a few minutes, but never gets actually running. Pool man says I need a new pump, but the first pump lasted 16 years, and the same pump (B849) the 2nd time lasts only 3 years? Doesn't seem right?

InyoPools Product Specialist  Posted: 3/6/2017 

Voltboy - Sounds like an issue with your Jandy RS control board. You will probably have to call Jandy (now Zodiac) on this one. Their number is 800-822-7933.

 Posted: 3/2/2017 

Ok check this out. When my epump starts up on its normal daily time it knocks my RS control panel offline. at the end of the time it turns off like normal and shows my panel back online and I can use any of the other pumps of features again. but while my main pump is on I can't do a thing on my iaqualink or the board. Wifi is showing still connected on the iaqualing box.

InyoPools Product Specialist  Posted: 1/25/2017 

MickeyGzzz - If your motor just hums and won't turn over, it's probably due to a bad start capacitor. I would replace the start capacitor. If that doesn’t work, you may have a short in the motor windings.

 Posted: 1/25/2017 

I have a pump with a start capacitor on the rear end of the motor and have a run capacitor on the top of the motor.
I swapped out the run capacitor on the top motor gets juice but only humming. Impellers are free moving
Would my next step to replace the start capacitor?

Thank you


InyoPools Product Specialist  Posted: 10/11/2016 

Bob - Sorry for the delay. we had a system issue. The replacement speed controller for your VS JEP1.5 pump is not in our system yet. I will see if is available and get back to you.

InyoPools Product Specialist  Posted: 10/11/2016 

glurge - Does the motor just hum when you turn it on? If so, you may have a bad start capacitor. See our guide on "How To Replace a Pool Pump Capacitor".

 Posted: 10/10/2016 

I have a US Motors 1081 Pool Motor 1.0 HP Model C55CXKMB-5012. It is fairly new only a few months in service. Today I tried to run it and it comes on for a few seconds, sounds like nothing is spinning and then cuts off. Any idea what is happening. It was working fine the previous day??

 Posted: 10/4/2016 

I just spoke with Jandy tech support. They said there's no replacement parts in the speed control box on the motor. It's a Gen II model JEP 1.5, by the way. Also said the speed control is now available without the motor, and to see about getting one installed. Would not sell me one. It's a recent release, part number R0688600. Can you give me a quote for one? I included my email address. Thanks again!

InyoPools Product Specialist  Posted: 10/3/2016 

Bob - Your pump problem could well be that you run capacitor is starting to fail. They are fairly inexpensive. I would try replacing it. As the capacitor fails, the terminal end of the capacitor starts to bow out.

 Posted: 10/1/2016 

I have a 1.5 HP motor Jandy Stealth pump with an AO Smith motor, about 4 years old. It was running fine, but then started running at varying speeds and stopping. It does not trip any breakers. If left alone it will start and run and pump, then stop after about 45 seconds. I've checked and there are no blockages, it seems electrical or controls related. Could this be due to the run capacitor going out? Thank you for offering all the advice to everyone!

 Posted: 7/30/2019 

Bob. I have had the same thing happen on my stealth. It's been shitty because I replaced fuses and reset the control box, just waisted so much time. I can run my pump at a low power, about 2400 without it shutting down, which I think indicated it is the thermostat related shut off getting over heated. I still hope I can find a mechanical reason for the struggle, but otherwise my main issue is replacing it and find a great pump which won't require too much replumbing. Did you solve your problem?

InyoPools Product Specialist  Posted: 9/7/2016 

pump stumped - Check to make sure you are getting 220V to the pump motor. If you have an older pump, it might be time to replace it. However you only have to change the motor. According to your specs, here is a link to your replacement motor.

 Posted: 9/5/2016 

I have a 1.5 Hp xp2 flow-master 220 volt pump . This is the main circulation pump in my bull Frog Spa. The pump is getting very hot and cycles off and back on once it cools down. I have switched the power from pump 1 and 2 on the circuit board and the other pump works fine so I have ruled out a relay I am guessing. Is their anything else I can do before I replace the entire pump? Any info would be appreciated .

InyoPools Product Specialist  Posted: 8/30/2016 

1.5 HP impeller - If the pool service guy thinks it's the impeller, I would have that looked at first. They are relatively easy to replace and much cheaper than a new motor. See our guide on "How To Replace A Pool Pump Impeller".

Anonymous  Posted: 8/29/2016 

My pool motor Hayward C4812N134C1 1.5 hp was put in 4 years ago, now not working my pool service guy said it is the impeller but said it is better to replace than repair as it may be something else. I changed my filter to 150 SQF clean and clear 3 months ago. Any suggestions if should consider fixing or replacing pump?

InyoPools Product Specialist  Posted: 8/16/2016 

2HP Jandy pump - When you shelter the pump, leave enough room around it for ventilation. Also, you might consider elevating the pump with additional pavers to help keep the motor vents free of debris. One customer did this and found a significant reduction in motor heat.

Anonymous  Posted: 8/15/2016 

Thanks for your prompt response. I think rather than pay $100 to have it checked and then an inflated price for a new motor, I will simply buy a new motor and put it in. I find 6 years on a motor a bit short but hot environment, rain, and direct sun is probably a harsh environment. I think I'll cover the equipment to see if I can get a longer life. Thanks again!

InyoPools Product Specialist  Posted: 8/15/2016 

2HP Jandy pump - If your pump is pushing water for even a second, you are past the startup circuits. I don't think a bad thermal protector would let your motor start, and if it did, it wouldn't overheat in a second. Low voltage might have been a problem, but you checked that. 6 years is an average life for a motor, so you may be due for a replacement. You might have the motor checked at a pool or engine store to see if they can find an answer.

Anonymous  Posted: 8/13/2016 

2hp switchless Jandy pump just stopped working. It hums for 1 sec and shuts off. It does move water during that second. Motor shafts spins freely as does impeller. Capicator checked ok but replaced with new one anyway. Voltage to pump ok. Still same behavior.

Can you help? Any thing else to check. Is it possible thermal protector is bad or must I replace a motor after only 6 years?



InyoPools Product Specialist  Posted: 8/10/2016 

Beyondfustrated - It sounds like your impeller is too big for your new motor and is overworking the motor - trying to push more water than the motor is designed for. Your pump id of S2444T is really the designation of your filter, so I don't know what pump you have. I guessing it is a Hayward Super Pump. If you have a 1 HP Super Pump with a Service Factor (SF) of 1.1 (on the motor label), you have an uprated motor and your impeller should be SPX2607C. See our guide "How To Understand True Pump Horsepower - Up Rated vs Full Rated" for an explanation of an "uprated motor".

 Posted: 8/9/2016 

We have a Hayward S244T Pro Series 1HP pump. Every year the motor goes out and we have it replaced The service company cannot tell me why this is happening. This last time they replaced the impeller and now the motor overheats within several hours and shuts off after it cools off it can be restarted. This has never happened before in the past. I have had an electrician out and he tells me it is not electrical. The motor is a century 1hp as well. Any insight on what the possible cause of our motor issues could be?

InyoPools Product Specialist  Posted: 7/28/2016 

DC - Unfortunately, we do not carry that brand of pump. Try calling Blue Torrent a 516-796-1626 to see if they can isolate your problem. Also, check to see if it is still under warranty.

 Posted: 7/27/2016 

We have a 1.5 blue torrent variable speed pump. it stopped working yesterday, it has all the lights lit up red but will not power on. This is only our 2nd season with this pump. Help?

InyoPools Product Specialist  Posted: 7/7/2016 

Bigboatswife - I would guess that your motor windings have shorted out and that your will have to replace the pump motor.

 Posted: 7/4/2016 

HELP!!!! We had a major downpour over night the filter and pump were running overnight as well. When we woke up we noticed the pump stopped working it was sitting in a pool of water! The water has since drained off and the pump still will not start. ANY SUGGESTIONS??? has a HAYWARD model C48K2N143B1 HP1 SP1607Z1M

InyoPools Product Specialist  Posted: 6/26/2016 

nkirkendall - If your pump is labeled as 2 HP and you are using 1 HP replacement pumps, the impeller in your pump is too big for your 1 HP motor. The 1 HP motor cannot drive the same amount of water that the 2 HP motor did and will overheat and eventually fail. You will have to downsize your pump's impeller to match the 1 HP motor. When you buy a new impeller, be aware of which "1 HP" motor you have, uprated or a full rated. See our guide on "How To Understand True Pump Horsepower - Up Rated vs Full Rated".

 Posted: 6/24/2016 

I have a Pentair SuperFlo pump model 340040. The original motor has been replaced 3 times now and keeps getting hot and shutting off after about 90 seconds. The pump is 2 HP and the motor is 1 HP. Would this cause this? The pool store has given up on trying to help saying they don't think that is my problem and to call an electrician. The electrician says everything checks out...Please HELP!!

InyoPools Product Specialist  Posted: 6/14/2016 

cjs - You might have hit on the problem. When you compare motors, you have to look at their actual or Total HP (THP) which is the product of the list HP times the motor's Service Factor (SF). If your original pump motor had a THP of ~2.0 and it was replaced with a 1 1/2 HP motor with an SF of 1.3, its THP was 1.95. The 2 HP impeller was being driven with a 1.95 THP motor - close enough. If your new motor has a THP of 1 1/2 (e.g. 1 1/2 HP x 1.0 SF) then your new motor may be driving more than it can handle and will overheat and very quickly fail.
If you find that your new pump is too small, you do have the option of downsizing the impeller (and maybe the diffuser) one size smaller.


 Posted: 6/14/2016 

It's the 1-1/2 HP installation guy again.
Thanks for your earlier answers. Much appreciated.

OK so I found after some research that this motor has a START capacitor. Since the motor does start, (but runs hot) doesn't that mean the capacitor is fine and the problem is somewhere else?

The motor did run for several hours before it shut down. Of course I don't know if it shut down due to the motor's thermal overload device or tripped circuit breaker. I turned it on once it cooled and ran fine. I didn't run it long just enough to see it pump.

Replacing the capacitor is easy enough and cheap. Now here's my next issue if it's not the capacitor, what's left? Stationery switch, governor? Could I have burned out the motor windings and/or thermal protection device by running the motor for several hours even though the motor is new?

I just found out that this pump is supposed to have a 2HP motor, not 1-1/2 which is what the old motor was!

Could it be that the impeller and diffuser are for a 2HP motor and it overloads the new motor but didn't bother the old one even though both motors are rated 1-1/2 HP? I'll check those parts in a few minutes to see if the part numbers match up with the HP.

Thanks again


Anonymous  Posted: 6/13/2016 

I'm the guy who replaced the 1-1/2 HP motor on his Super Pump II from yesterday. Well now it's running hot, but running without tripping the circuit breaker or thermal breaker on the motor. Now I wonder if running this way will do damage to the motor. The motor is running quietly, pump working normally.

InyoPools Product Specialist  Posted: 6/13/2016 

Super Pump II shut down - I would replace the capacitor first. You might get lucky. Then look at the other electrical parts that may have been damaged. See our guide on "How To Replace AO Smith Motor Parts - Overview". If you accidentally shorted out the motor windings, you may have to buy another motor.

Anonymous  Posted: 6/11/2016 

Recently replaced 1-1/2 HP motor on my Hayward Super Pump II with an A.O. Smith/Century model UST1152. New seals etc. When I first ran it it tripped the circuit breaker. Then I noticed I had scraped the insulation off one of the wires to the capacitor which shorted out the motor. So I wrapped the wire with black electricians tape. The pump then ran fine, quietly but ran hot. After about an hour the circuit breaker tripped. Waited for it to cool and started it again. It ran fine. quiet (just a mild run sound of the motor and water hissing through the pipes) again pump ran well. I shut it off then no use and overheating it again and causing real damage. What could be the issue? Should I replace the capacitor? Could I have burned it out when it shorted out. All the other parts are to spec, or unchanged. Appreciate some guidance. Thanks

InyoPools Product Specialist  Posted: 5/31/2016 

Noel wooden - If the pump was not circulating water for a period of time, you may have shorted out the windings in the motor and will have to replace the motor. If you are lucky, you may just have a bad start capacitor, which would be much easier and cheaper to replace. Check that first if your motor has one. See our guide on "How To Replace a Pool Pump Capacitor".

 Posted: 5/29/2016 

Our circulation system is located at the bottom of the pool. My husband pushed them down without knowing while I was vacuuming the pool. At first it was running fine, but as soon as I turned it off to unhook the vacuum and turned it back on the motor made a humming noise. Now it will not even come on. The timer has even stopped running. By him pushing them down and the water not being able to circulate back into the pool could he have burnt the motor up or should of the pressure from the water had kept them up. Back a few months ago the motor had made a buzzing noise but stop and was running fine.

InyoPools Product Specialist  Posted: 4/4/2016 

djd - Generally this is a voltage problem but if you haven't change any of the electrical - replaced the motor, changed the location of the pump, changed the gauge of wire to the pump - the problem may be mechanical. Check first for a clogged impeller. See our guide on "How To Clean Out a Pool Pump Impeller". Then See our guide on "How To Troubleshoot a Pool Pump Motor - Motor Overheated".