As pool technicians, we hear these everyday:
“My pump is on but the water is not moving.”
“Why is there water leaking from under my pump?
“Why is my pump losing its prime?”
And the classic but vague, “My pump isn’t working, what’s wrong with it?”All these and many others are signs of a failing pool pump but the source of the fault varies. The key to diagnosing the pump is understanding its parts’ functions and what happens when a certain part is failing. Knowing what to look for allows you as a homeowner to identify and fix the problem yourself, thereby saving money. Or if you’re not up for the job, be able to explain the issue to a pool technician so they can fix your pump. Most importantly, being educated on your pump prevents you from being pushed into buying unnecessary parts by your Poolman.
We’ll do a rundown of the 8 most replaced parts on a pool pump with an explanation of each part’s function and the symptoms of a possible issue.
1.) Motor
Symptoms
- Grinding or Screeching – A sign of bad bearings caused by age or rusting. Bad bearings are also a sign of a leaky shaft seal.
- Loud Hum – If the shaft is spinning then it is likely the capacitor failing. If the shaft is not spinning then the bearings have frozen and locked up the shaft.
- Flipping Breaker- A deep internal component within the motor has failed and requires the motor to be replaced or rebuilt.
- Silence – The shaft of the motor has frozen providing you with a new 30-pound paperweight. There is no chance of rebuilding the motor, the only route is to replace.
A pump’s motor is the heart of your pool. Put simply, if it’s not a pumping then you’ll be a slumpin’. Generally, motors have a lifespan of 3 – 5 years. The life of a motor can vary greatly upon the conditions it endures in its application. A motor exposed to the summer sun, spring rain and early fall freeze will likely burn out quicker than a sheltered one. If you’re concerned about weather effects, we suggest using the Universal Motor Cover to protect your investment.
The Fix: How To Replace the Motor on Your Pool Pump, How To Wire A Pool Pump,
2.) Seal Plate
Symptoms
- Obvious wear and tear, i.e. cracks
The seal plate is the joining point of the motor and the pump housing. Damage to the seal plate is usually caused by an over-tightening of either the motor or housing bolts. Excess tightening will cause cracks in the frame and eventually form leaks.
The Fix: Replace Seal Plate
3.) Gaskets & Seals
When someone says they are seeing wet cement on their pump pad, the usual cause is a bad gasket, shaft seal or o-ring. These rubber parts seal the joints of your pump making it watertight. Each seal failure will affect your pump in a distinct way. If your pump requires multiple gaskets replaced, we suggest applying a Gasket and O-ring Kit (GOKIT) if available. We also have a guide on installing a gasket kit: How To Use a Tune up / GO-KIT
Shaft Seal
Symptoms
- Water dripping from motor vents
- Loud bearings
- Rusty motor casing
- White whirling on motor face
Arguably the most vital and sensitive of the bunch, this $12 – 20 part is the last line of defense protecting your $200 electric motor. And I shouldn’t have to tell you but water and electric motors do not get along very well. The seal consists of two sides: a white ceramic ring sleeved in a rubber protector and a spring-loaded side with a carbon ring. If your shaft seal begins to fail, water will leak into the motor casing. This small leak will begin the process of corroding bearings, copper windings or electrical components. Friendly reminder, whenever replacing a motor always replace this seal.
The Fix: How To Replace a Pool Motor Shaft Seal
Housing Gasket
Symptoms
- Wet pump pad
- A leak coming from the seal plate and housing seam
The largest of the gaskets acts as the seal between the seal plate and pump housing. Diagnosing a faulty housing gasket is easy due to its location. If water is spilling from the large seam between the pump seal plate, then this would be your culprit.
The Fix: How To Replace Pool Pump Gaskets
Lid Gasket
Symptoms
- Large air bubbles in the strainer basket
- Low water pressure
- Takes longer to prime pump
“Why am I getting air in my system?” The answer to that question always begins with checking the lid o-ring of the pump. Unlike the other gaskets on the list, a bad lid gasket causes a sucking leak rather than a blowout. The usual sign of a bad lid o-ring is larger than normal bubbles in the strainer compartment. The air leak may also cause a hissing sound.
The Fix: How To Replace Pool Pump Gaskets
Diffuser Gasket
Symptoms
- Losing prime
- Low water pressure
This important but sometimes forgotten part, the diffuser, and its gasket enhance the pulling power of the motor and impeller, enabling the pump to prime itself. Located at the tip of the diffuser, the gasket seals the diffuser/impeller assembly to the front part of the housing. The funnel-like diffuser is then able to focus the impeller’s pulling energy, increasing its strength. This aids in priming and maintaining water pressure.
The Fix: How To Replace Pool Pump Gaskets
4.) Impeller
Symptoms
- Losing prime
- Low water pressure
The motor may do all the spinning, but the impeller does all the work. Found screwed onto the end of the motor shaft, the impeller is a vented or veined disk. These veins act as a boat propeller would, drawing in and then pushing out the water. If your impeller is broken then you will see little to no flow of water. There may be rattling as well caused by broken pieces of the impeller within the housing.
The Fix: How To Replace A Pool Pump Impeller
5.) Diffuser
Symptoms
- Low pressure
- Loss of prime
The diffuser is a cone-like shroud that sits over the impeller. Its main function is to focus the impeller’s pulling force towards the pool to enhance the water draw. A broken or cracked diffuser will have cracks that siphon off the impeller’s pull, lowering water pressure.
The Fix: How To Replace A Pool Pump Diffuser
6.) Strainer Lid
Symptoms
- Large air bubbles
- Obvious or hairline cracks
- Warping
The strainer lid is the main visual inspection point of your pump. Or in simpler terms, it’s where you check to see your pump is running. Lids become brittle with age and can break or warp from excessive sunlight. Hairline cracks in a cover can create a sucking air leak allowing air to slow your system.
The Fix: Replace Strainer Lid
7.) Strainer Basket
Symptoms
- Rattling noise within strainer basket
- Clogged impeller
- Torn or damaged cartridges
The strainer basket catches debris before it reaches the guts of the pump. A broken basket can harm your pump or filter because it misses debris that can damage the impeller, diffuser or filter cartridges.
The Fix: Replace Strainer Basket
8.) Housing
Symptoms
- Dry rot
- Cracks forming near ports or bolt holes
- Obvious wear and tear
Considered the hull of the pump, a housing encases all of the above parts. A pump housing failure is usually seen coming because of the obvious long-term degradation of the pump. The sun is usually the biggest culprit when it comes to housing damage. The pump getting baked during the summer months will cause the housing to start petrifying and becoming brittle. Cracks will begin to show around the stress points. The housing is the second most expensive part on a pump to replace, only behind the motor. If the housing and a few other parts need replacing, it may be best to replace the whole pump. Read our previous blog on determining what to do in this case: Pump or Motor: To replace or not to replace… That is the question.
I purchased a brand new Hayward 1.5 pump for inground pool. It worked at first but once it ran for about 15 minutes it stopped and once it cooled down it started again. I notice it keeps flipping the breaker. Do I have to install a new breaker and wires? It’s also hooked into a timer that doesn’t work anymore so I just shut the timer off and use the switch. But still the same thing keeps happening. What do you suggest?
First I would try moving the pump to a different breaker to make sure it is still operational. If the motor still works fine on the different breaker, then I would switch out the breaker. Also, test the original breaker and circuit wires to confirm they are still viable.
Hi…my girlfriend’s pump isn’t working. When she plugs it in…it hums but motor does not spin. Help?!
It could be the pump motor’s capacitor. What is the part, catalog, or model number on the motor label?
My pump was on and it just stopped I tried to press the button for testing and is stuck
Gladis, what is the model number of your pump motor? Did the motor flip the breaker?
I have an above ground pool. When installed the pump was not screwed to anything so it’s just sitting in plastic. When I started pump up it was leaking badly where the two pieces of pump go together where the screw area is on outside of Hayward pump. I have this problem a lot. I think it could be not screwed tightly enough at connection. But the plastic part in skimmer part is connected. Any thoughts?
What is the model number of your pump? I can show you a parts breakdown, so we can figure out exactly where the leak is coming from and which parts to replace.
Thanks for your great help! My variable speed pool pump was working just fine & now the lcd unit used to program said pump will not stay on, meaning that it flashes on/off every 10 seconds and the pump won’t work. I have checked circuit breakers, etc but no luck. Please help…I’m going insane!
First, I would check if your motor is still under warranty. If so, contact the manufacturer immediately to initiate a claim. If not, you may need to replace the variable drive controller. Some motor manufacturers do not offer a replaceable drive or if they do, it could be the price of a whole new pump.
Pump motor isn’t turning on. I checked voltage and it’s getting power any suggestions?
Hayward super pump is controlled by intermatic model 154-00456. I can hear the timer gears moving and checked with multimeter that both timer and pump have power. But there’s no noise at all from the pump when I turn the manual knob on the intermatic. Removed the motor assembly from the wet housing unit and was able to spin the shaft by turning the impeller with my hand. Also checked the capacitor with multimeter. It seems to be charging and discharging. At a loss
Does the motor fire up when the timer activates it for its normal schedule (i.e. not using the manual switch?) Was the motor creating any odd sounds before this switch issue started?
I suspect there is a part deeper within the motor that has failed. You will likely need it tested by a motor shop. But you can get some free advice from our friends over at TroubleFree Pool Forum
0/09/17 Happy New Year! I ran the pump overnight for cold weather (at 38degrees when started) in Apopka, Florida. It worked fine overnight on previous day. When I checked to see if it was still generating chlorine the digital readout stated “no flow” but motor sounded normal.
I took off the clear cover over pump basket area and it was full & steaming hot and filter also dry so no water went through. Pool return was bubbling (maybe blowing air)? Impeller, diffuser or cap issue? Please heeeelp!
Hi There was a car accident yesterday which caused a power outage for about an hour. since then my pool pump hasn’t worked.
Lorraine – have you checked your breakers to see if they have been tripped?
I have a similar issue where, after flipping the tripped breakers, the display shows the filter operating but the pump is not running. When I reset the breakers, I hear a “pop” coming from the pump but nothing happens. Any ideas? Thank you.
I have an in-ground liner pool. I recently upgraded both the pump and filter to larger horse power and capacity respectively. The psi usually shoots up to 20 and the Kreepy will not work. I noticed that when I take the filter element out, the psi drops to 10 and the Kreepy works just fine. The filter is new – any suggestions???
Jim – to figure this out, we will need more information about your pool upgrades. What are the model numbers of your pump and filter?
My pump is humming and doesn’t flow water what could it be changed the rod in the impeller it was broke now it still isn’t working can it be cause by not enough water in pool I’m lost
A humming motor is a sign of a bad capacitor. What is the model or part number of your motor?
I have a Hayward pump from quite a few years back.
I did a smoke test and saw the smoke is sucked into the pump area.
Is this sign that there is an air leak and my pressure will not go up further (always sitting at no more than 7psi), and therefore would not prime.
What do I look for next?
If the smoke is drawn into the pump than that is a definite sign there is an air leak issue. Where on the pump is the smoking being drawn in?
It is definitely beyond the strainer housing. Somewhere around the seal plate and motor mounting plate area. Do I need more test to pinpoint the location?
From what I read, do I need to change the gasket by removing the motor? or something else?
Is it a complicated procedure requiring special tools?
Also is a normal pump supoposed to be quiet during its normal operation?
Thanks
Oliver
Here is a guide on how to install all the gaskets of a pump: How To Use a Tune up / GO-KIT
Quiet is a relative term. But I would say you should be able to carry on a conversation with a person standing next to the pump. If you hear a grinding or a scraping, then you may have more problems than just a gasket.
Following a recent evening power outage, the pump fails to run. The display reads as if it were running, I flipped all the breakers and still nothing. Any advice or guidance is greatly appreciated…
The display you are reading, is it on a motor mounted control or is this on a standalone pool controller like a Jandy Aqualink?
I am trying to find out how to make sure my pump is connected properly because Walmart sold me a pool with the wrong pump gave me the right one but no instructions
If you have the model number or make and model of the pump, enter it with “owner’s manual” after it. Instructions should pop up eventually.
I have same problem any answers
My husband tried to clean the basket filter near the pump while the pump was still on. The water that gushed out of the filter went into the pump. Now the pump will not turn on. Is there a solution to this or was the the end of our pump?
pump is making a load noise and it’s not sucking in or blowing out water. What could it be? Thanks, Kimberly
In this article, we mention a few things it could according to the sound. If you want to troubleshoot the motor read this guide: Pool Motor Troubleshooting
I replaced my 1 hp pool pump motor over the weekend. I installed exactly the way it came out, but the motor will not come on. I had an electrician friend test for power at the leads on the motor and it is receiving power. I took it back to Pinch-a-penny and the motor tested fine. They went ahead and gave me another motor, but the new one isn’t working either. I’m totally lost on why it isn’t working. Any suggestions? Thanks in advance.
Do you have the motor set to the correct voltage? If the motor you received is a dual voltage it comes set to 230 volts it will not work if you are running 115; you will need to set the voltage using the knob or jumper switch at the back end of the motor.
I have the same problem. I received a Pentair Optiflo 1.5 HP 2 speed above ground pool pump that is an exact replacement for my old pump. It’s rated for 115v. Plugged it into the outlet and nothing happened. I checked that power is getting to the outlet and even tried plugging the pump into an outlet unrelated to the pool and still nothing. Any recommendations? Thank you.
Here’s my problem, why my impeller is not moving at all? 🙁
My motor is leaking/dripping from a plug . Is this an easy fix or should I call someone? Pump has been off now ten hours 🙁 . When i shut off motor water shot out and lid popped off . How to to fix:( new to this pool thing just moved in haven’t even used the pool yet.
So, is water leaking from the pump’s drain plug? Motors do not have plugs, at least not that I know of.
What is the model number of your pump? I have not seen a pump lid pop off, after it was turned off.
Pump leaking at housing interface. The pump/impeller don’t seat all the way into the housing any more. I didn’t make any changes and cannot get it to seat all the way in which is causing it to leak at that point. The large screw ring is tight as I can make it.
What is the model number of your pump? It could be a warped seal plate or a bad lock-ring.
Have you checked that the housing oring is not pinched between the housing and the seal plate?
Pump keeps loosing prime. The water in the skimmer rises and falls in correlation to the pump flux. I’ve clean skimmer and pump baskets. Checked the seals and impeller. I’ve noticed hairline cracks in the impeller but no missing pieces. I see no signs of leakage or loss of water. The water is clear.
Any further ideas?
Have you checked your suction side for air leaks? Have a read of this how-to guide: How To Determine Why a Pool Pump Won’t Prime
Skimmer wier
Pump primes well but seems to lose suction after about 10 minutes. I replaced the impaler and gaskets about a month ago. Please help
Have a read of this how-to guide: How To Determine Why a Pool Pump Won’t Prime
The spindale (rod) on the inside my pump keeps braking. Why?
Can you be a little more specific? Are you taking about the shaft of your motor is breaking?
Hey bud my pool got to low now my pump isn’t pumping the water into pool. Do I need yo reprime the pump? If so how do I do that
First, add water to your pool to make sure skimmer isn’t gulping air. Use a regular garden to prime your pump, guide: How To Prime a Pool Pump
Hi!! We are losing prime on our pump after about 2 hours. I believe there’s a pinhole in our filter housing and a crack at the top of the filter housing. It is slowly leaking. Would this be the cause of the loss of prime in the pump?
The filter is on the pressure side of the pump. Sucking air leaks are more likely to occur on the suction side of the pump; meaning in the plumbing lines or valves before the pump.
Take a moment to read some of our how-to guides on finding air leaks.
I’m trying to drain my pool down using the maon dtain, but the pump doesn’t work now that the water level is down about half way. Skimmer is closed off. I replaced seal and gaskets. Tried prming. Still won’t pump. What am I doing wrong?
Joe, how are you closing the lines to the skimmer? Are you closing it with a diverter valve or plugs? Have you checked for air leaks in the lin i.e., elbows, valves or tees? Does your skimmer have an equaliser line that is not closed?
Pump runs great. is when I connect the hose and barracuda that looses suction and doesn’t clean. what do you think it is?
Check the hose sections fo air leaks; there may be a few pinhole sized cracks that are killing your suction power. Cover the ends, then submerge each hose length, if you see air bubbles then you got a sucking air leak.
Thanks Matthew for the advice on what might be wrong and what kind of pool pump repairs I need to remedy the situation. Hopefully the motor isn’t shot on my pump! I will call my pool contractor as soon as I can.
Thank you, Casey. Hopefully it is a cheap fix!
My pump is flowing backwards
Reverse the hose lines into the pump housing.
My pool is not flowing, I had work done on it 2x. 3 seals has been changed and now it is back to little or no flow.
Thanks for the question, Gail.
The normal culprit’s for a pool pump’s low flow are trapped air pockets, clogged lines, sucking air leaks, or impeller issues. Fortunately, we have a guide on troubleshooting a pool’s low flow problems, take a look: How To Determine the Cause of Low Water Flow
Ugh having same issue. Third pool
My pump is flowing backwards. The end that water should be coming out from is actually sucking the watter through that end.
If this is a new pump, your plumbing lines are hooked up the wrong way.
A motor would not be spinning backward unless it was three-phase, that was incorrectly wired. Three-phase motors are usually only on large commercial pumps.
Did you clean out your desander filter if you don’t this will cause the pump to have very low flow
My pomp does not pump water into the filter and then back into the pool
Is this a new installation? If so, then you may have plumbed the lines incorrectly.
If it is not a new installation, where is the water going? Does the pump turn on at all? Does a breaker flip?