How To Determine Why a Motor Won't Start or Shuts Off

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This guide discusses the common problems related to a motor that won't start or once it does start shuts off after 5 minutes.

Step by Step

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Step 1

No power to the motor- Check for improper or loose connections, open switches or relays and blown circuit breakers or fuses. Check for broken power cords.

Step 2

Jammed motor - Check that the motor shaft rotates easily. If it's stuck, check that the impeller is not jammed with debris. Check that the impeller or diffuser is not broken. If the impeller is good, your problem may be bad motor bearings. Replace bearings/motor or impeller as required.

Click here to view motor bearings. 

Click here to view pump impellers.  
 

Step 3

Motor hums but will not turn over - Check for a bad capacitor. You may have two: a run capacitor and a start capacitor. Some motors have a governor at the electrical end of the shaft. Check that it is not stuck open. If your capacitor(s) and governor are good and the motor shaft rotates easily you probably have a burned out motor coil and you will need to repair or replace the motor.

Click here to view motor parts.  
 

Step 4

Motor gets hot and shuts down - Generally due to low voltage or being overloaded. Check that the motor is wired correctly. If the motor is configured for 230V and has 115V coming in, it will shut down after running 3-5 minutes. Check for loose connections. Check for undersized wiring. For a hook-up to the circuit box of under 50', pumps of up to 2HP wired for 230V need No. 14 size wire, For pumps wired for 115V, the wire size must be No. 14 for 1/2 and 3/4 HP; No 12 for 1 HP; and No. 10 for 1 1/2 and 2 HP. Check that the motor is not overloaded. Does the pump have the correct impeller and diffuser for this motor? Is the impeller worn and rubbing on the diffuser. 

Step 5

Note: Most pump motors have Automatic Thermal Overload Protection. The motor will automatically shut off before the motor generates enough heat to damage itself. Once a normal heat level is reached, the motor will automatically restart. CAUTION: If the motor operates in this on/off mode for any length of time it will burn out.

Click here to view replacement motors. 

Comments

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(1 to 40 of 225)

 Posted: 2/22/2022 

I have a 1081 US Motors pond pump that was running fine and had been on for a couple of week, (usually I turn it off at night). I turned it off to do so cleaning of the pond and couldn't get it to restart, click, circuit breaker, etc. Finally got it started using a screw driver at the end to turn the shaft while the switch was on. Seems to be running fine, but now no water being pumped. Can't reach to the impeller to see if it jammed. SUGGESTIONS PLEASE?
 Reply

InyoPools Product Specialist  Posted: 2/23/2022 

Going by the description of how you got it started, either you have rusty bearings, a bad capacitor, or a clogged impeller. Suggestions: If your motor makes loud screeching noises when it runs, you have rusting bearings and either need them replaced or replace the whole motor. Troubleshoot the capacitor and replace it if necessary. To check the impeller, open the pump to check for debris. Unfortunately, pond pumps are built differently than pool pumps, so I can't help much with that.
 Reply

 Posted: 12/12/2021 

We just bought a used Century HSQ125 pool pump. We installed it and the pump starts but after a few seconds it stops and starts making a clicking sound. Not sure what it is or how to fix it?
 Reply

InyoPools Product Specialist  Posted: 12/13/2021 

I'd start by checking the motor voltage setting and test the voltage coming from the power source. I guess that your circuit is not getting enough power, which isn't allowing the motor to get to the correct revs. That clicking sound would be a centrifugal switch problem. We cover a similar question in this video: PSC #16 - Pump Motor Making Clicking Sound
 Reply

 Posted: 11/9/2021 

I replaced my pool motor. My GLX-PCB- PRO relay clicks but motor will not turn on. motor: L1 has 120v L2 has 120v and its grounded.
 Reply

InyoPools Product Specialist  Posted: 11/10/2021 

Do you have the motor to accept 240 volts? Does your 240-volt circuit resemble the setup shown on page 16 of the Aqua Rite Pro manual?
 Reply

 Posted: 8/18/2021 

Replace the motor on my pump replace brakes and still working on low high speed for les that 30 seconds
 Reply

InyoPools Product Specialist  Posted: 8/19/2021 

What brakes are you referring to?
 Reply

 Posted: 8/18/2021 

I replaced a Hayward 2.5 motor with the same model. It worked for about a week but now it is tripping the circuit breaker. Any ideas why that is happening?
 Reply

InyoPools Product Specialist  Posted: 8/18/2021 

Yes, we mention most of them in the guide. I could venture a bunch of guesses, but honestly, they would just be a guess. If you want to know the reason why your specific motor has failed, the only way to do so is to run through the steps listed in the guide above. 
 Reply

 Posted: 8/14/2021 

I just installed a new Hayward above ground filter. Upon start up, all the valve cycles work as they should, but when I set to filter my Century pump begins to cycle with an odd clicking sound. It doesn't cycle on and off, just from very low to normal speed. It does this about a half dozen times then shuts down. It doesn't blow the breaker. Could this be caused by a flow problem, not my pump? or what would cause the pump to malfunction like this?
 Reply

InyoPools Product Specialist  Posted: 8/17/2021 

The motor might not be getting enough voltage, which is preventing the motor from running at full RPMs. if that happens, the centrifugal switchwon't stay open, that clicking sound is it repeatedly opening and shutting. We discuss this and more possibilities in this guide, give it a read - PSC: Pump Motor Making Clicking Sound
 Reply

 Posted: 8/13/2021 

My Hayward Super Pump just stopped working. Nothing happens when I switch it on. The timer is running and the pool light turns on, so I assume power is getting through. I did notice that the basket to the pump was incredibly full. I'm still new to pool ownership so I was failing to check that. I worry that maybe the pump is burned out? Or maybe there is just debris in the impeller?
 Reply

InyoPools Product Specialist  Posted: 8/17/2021 

The only way to figure out if the motor is burnt out is to test/troubleshoot it. Use the steps in the guide. If you have a question about a particular step, I can help you. But I can't tell you exactly what the problem is from that description. If the basket is clogged, the pump may have run dry or overheated. But as to the extent of the damage, that won't be known until you test it.
 Reply

 Posted: 8/4/2021 

My Century 2-speed AO Smith pump is about 10 years old and just stopped working. It makes a quick humming noise about every 90 seconds but never gets going.
 Reply

InyoPools Product Specialist  Posted: 8/5/2021 

Step 3 describes your scenario and the cause is usually the start capacitor.
 Reply

 Posted: 7/10/2021 

The motor( a.o. smith 2 speed 196159/ Jandy stealth) only turns on in the low mode but not high, unless its running in low first and then the high mode will work, for a short period and shuts off. If you try high mode first it just makes one click sound. I think it ran dry recently because it did not prime properly, skimmer door sometimes sticks.
 Reply

InyoPools Product Specialist  Posted: 8/4/2021 

There is likely a wiring issue, causing the high speed to malfunction when you select it.For a more in-depth explanation, read the following guide - Pump Runs On Low Speed But Not On High Speed
 Reply

 Posted: 6/2/2021 

I have a Hayward pump and it initially ran for about 20 minutes then I turned it off to finish cleaning the bottom of the pool. When I went to restart it now it makes a light couple of clicking sounds almost like a gas engine that wont turn over. I replaced the leaky o ring and checked all the breakers but I'm at a loss on what the issue may be
 Reply

InyoPools Product Specialist  Posted: 6/4/2021 

I suggest testing the pump's start capacitor and the line voltage to see if those are the things preventing start up.
 Reply

 Posted: 5/22/2021 

I just walked outside and my pool motor has stopped. The electric switch is in the on position and it won't go down to the off position. The breaker box switch was still in the on position as well. It was working fine last night
 Reply

InyoPools Product Specialist  Posted: 6/4/2021 

Have you checked to see if the motor is jammed? Have you tried resetting the breaker anyway? Have you done any troubleshooting other than checking the breaker?
 Reply

 Posted: 5/15/2021 

I installed my pump, I have power to the pump ((tested 240) but pump will not turn on. No sound at all. Checked old pump and same thing. What could be wrong if units are getting power?
 Reply

 Posted: 2/20/2022 

I’m having the exact same problem. We’re you able to fix yours?
 Reply

InyoPools Product Specialist  Posted: 5/21/2021 

You could have a bad breaker, loose connection. It could be a host of things. Do you have a multimeter that will help you test the voltages? 
 Reply

 Posted: 1/5/2021 

My pool pump makes a humming noise but won't turn on. Replaced capacitator, however, it keeps doing the same thing. What else could it be?
 Reply

InyoPools Product Specialist  Posted: 1/6/2021 

If the motor still hums after replacing the capacitor, the phase windings are most likely bad. If that is the case, we usually suggest replacing the motor. You can see more on how to test the windings here: How To Use a Multimeter to Test a Pool Pump Motor - Winding Resistance
 Reply

 Posted: 8/25/2020 

I replaced a LAo1N Booster pump for our cleaner with a brand new one eight weeks ago. It was working perfectly until a week ago. Tropical Storm Isaias created havoc in the Northeast and our house ran on generator power for the better part of 6 days while they repaired the power lines. Our pool equipment all runs on the generator as well. It was somewhere during the storm/post storm that the booster pump stopped working. The filter pump is working great. I checked all the wiring on the pump and on the control board and all looks in good. Lights on control panel light you push the cleaner button. The pump does not hum, get hot, nothing. Just dead. Any ideas? I am wondering if there was a power surge or something that damaged it but not the Filter pump. Thank you
 Reply

 Posted: 3/2/2021 

Have you had any luck fixing your pump? I have the exact same problem as you we froze up bad here in Texas a couple of weeks ago and now my pump won't turn on at all but I am getting power to it and the capacitor is good and the impeller spins easily
 Reply

InyoPools Product Specialist  Posted: 8/27/2020 

There could have been a power surge that knocked out your motor, but I would not rule out water damage. Try checking the capacitor: How to Test a Pool Pump Capacitor, and try spinning the motor shaft by hand to see if it has frozen up.
 Reply

Anonymous  Posted: 8/8/2020 

It rained a lot last night my panel was open I believe it got wet inside the pump turn on but then it turned off now it won’t start
 Reply

InyoPools Product Specialist  Posted: 8/20/2020 

The only thing you can do is give it time to dry out (a day or two) and hope that is all that needs. If not, you may need a new controller or motor.
 Reply

 Posted: 7/20/2020 

My pentair 342001 vs superflo will not start. if i hit a few buttons all the small green led lights will flash twice. Sometimes once. There is no error code, I have tried the breaker. Help?
 Reply

InyoPools Product Specialist  Posted: 9/9/2020 

It sounds like you have a bad control. Your best option is to contact Pentair to see if they can troubleshoot the panel. But usually, when they start acting up, you need to replace the control box or the whole motor assembly. How old is the pump? Is it still under warranty?
 Reply

 Posted: 7/16/2020 

My pool pump won’t turn on at all. There is no humming sound. The box is getting power but motor is not working. It is a Century switchless pump. Aqualink RS6 control panel shows the filter pump is lit up but nothing happening. Thoughts?
 Reply

InyoPools Product Specialist  Posted: 11/10/2020 

If you disconnect power from the motor, disassemble the pump, can you turn the motor's shaft by hand? Or, is the shaft locked in place, sometimes called "frozen"? If the motor shaft is frozen, your bearings have locked up; you would need to either replace the bearings or the whole motor.
 Reply

 Posted: 5/31/2020 

I've had this pump for less than a year n I plugged it in this year n no power to the pump !! What am I missing?
 Reply

InyoPools Product Specialist  Posted: 10/23/2020 

This guide tells you what to do in this case. Did you take the time to read and complete the steps?
 Reply

 Posted: 1/13/2020 

I just replaced my pump and and noticed that it will not turn off at the control panel even though it reads "off" on the display panel. It will only come on and go off by using the breaker. Any ideas on what caused this?
 Reply

InyoPools Product Specialist  Posted: 1/13/2020 

For some clarification, is this a single, dual or variable speed motor? When you say control panel are you rferring a mounted control on the motor, or a wall-mounted panel?
 Reply