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Why Is My Pool Pump Leaking

By January 12, 2021Swimming Pools
Why pool pump leaking

In the Southern part of the US., many homes have a pool or at least a community pool to go to.  Our weather is ideal that we can use our pools for almost 12 months a year (in some places).  Even though we all probably maintain our pools properly, there can still be issues that occur. 

One of those is the pool pump leaking. Why does this happen?  It can be due to broken seals, pump housing, pump drain plugs, improper fittings, or the lid to name a few.

Let’s look at why this is important, the different reasons why the pool pump is leaking, as well as other reasons it may not be working, grading of the land, pool safety, and when to call a professional for help.

Why This is Important

A pool pump consists of a motor and pump basket housing.  Pool pumps create the water that flows through the pool, carrying the chemicals and evenly distributing them in the water.  Then it carries the water to the filter, heater (if there is one), and chlorinator so that the water is safe to swim in. 

If the pump fails, the system will get hot and can start a fire. It also can’t filtrate the water and will allow algae growth.

1. When the Seal Breaks, the Pool Pump is Leaking

Every pool pump has a seal around the mechanical shaft that keeps water from leaking behind the impeller.  If the seal gets old, then water goes down the backside of the seal plate and then through the hole where the mechanical shaft goes.

How do you know if it is the seal?  You need to bend down to look at it closely and make sure it is not something else like water from the pump outlet fitting or a clamp that is loose.

How to Fix the Seal:

1.Find out the make and model by looking at the label on the pump housing

2. Take this information to a local pool store and they can give you the new seal.

Watch this video below for steps to fix the seal: Note: all models are different so consult a guide if you try this yourself.

If you don’t feel comfortable fixing it, contact a professional

2. Pump Housing

The pump housing can also leak water where it connects to the seal plate at the wet end of the pump.  Additionally, it can leak water at the dry end of the pump if the bolts or clamp are loose or the O- ring is not sealing as it should.

If there is a freeze, the pump can freeze as well and stop working.  This will require you to purchase a volute to repair it or call a professional for help.

Pump drain plugs
Pump drain plug

3. Pump Drain Plugs

These pump drain plugs can also cause water to leak if :

  1. They are missing O-rings
  2. Drip when the pump is off
  3. Take in the air when the pump is on
  4. Teflon tape was not used for installation- the tape ensures there are no leaks when applied properly

4. Outlet Fitting Leaks

Sometimes people think this is the shaft seal, when it is actually not.  To fix this fitting, replace with a fitting and a coupling.

5. Inlet Fitting

Located on the inlet side, if the pool pump is located below water level, a loose fitting or fitting that shrunk can draw air in when running or leak water when it is off.  If the fitting isn’t too loose, pool putty or silicone sealant can fix it.

6. Pump Lid

The pump lid can leak water and does need replacing sometimes as it is in the weather elements or can crack. If it is leaking water when the pump is off, the pool pump is leaking and you need a replacement lid. The pump lid O-ring needs to be tight and have lubrication in order to make a seal.  However, don’t use Vaseline.  Take a look at this short video for why! 

Not Leaking Water But Just Isn’t Working

Here are some other ideas as to what may be causing this to happen:

1. Loud Screeching Noise or Sounds Like Rocks in the Pool Pump

This can be due to not enough water getting into the pump.  Check the suction lines to make sure not too many are closed off. Also, check the skimmer to see if there is debris and clean it out. It is also possible the pump may be too powerful and you need to get a different motor.

2. Pool Pump Hums and Doesn’t Start

This could be an issue with the impeller.  Turn the power off and then unscrew the bolts in the middle of the pump body. Take out the assembly, remove the gasket away from the impeller and take out any debris you see. Put it all back together.

3. Pool Pump Sucks Air

This does not happen if the lid is airtight.  There could be other things going on like the pipe entering the pump could have an issue, the valve stem on the suction valves, or impeller, O-rings, or gaskets can be malfunctioning.  Check for cracks, leaks and fittings that may be old or loose.

Pool pump motor doesn't work or turn off while running
Pool pump motor

4. Pool Pump Motor Doesn’t Work or Turn Off While Running

Make sure the pump is on if you are not getting power.  If it is, it could be a capacitor that is bad.  If your motor is old (most last 8-15 years), you will want to think about replacing it instead of just the capacitor. You may need a professional to do this for you.

If the motor turns on but power is lost, it could be overheating.  Try this again in the evening in the cooler hours and see if it makes a difference. If not, you will need to contact a professional to see if you have a bad motor or pump.

5. Pool Pump Flow Rate is low

This could be there is something blocking the pump or the filter.  One place to check is the filter to make sure it is clean.  This in turn will allow the pressure to reduce and then the flow will be reset and go back to the pool pump. 

Remember, it is important to have the pump fixed as it can lead to a lot of bigger problems if not taken care of.  This is something that will also come up on a home inspection report,  whether you are trying to refinance or sell the home. It is important the repair is done properly.  A swimming pool is a big investment in your yard and needs to be taken care of for the safety of you and others.

Grading of the Land

One way to also keep the pool motor and pump clean and functioning is to make sure the land is graded appropriately. Negative grading can cause mudslides and other debris to go into the pool or to the equipment pad area and cause the system to stop working. Keep an eye out for this when you are outdoors and fix this right away as it can lead to bigger issues down the road.

Pool safety
Fence around a pool is a great safety measure

Pool Safety

Swimming pools are a lot of fun, but you want to make sure that children (and adults) are safe. 

Keeping people away from the equipment pad is a great idea to make sure nothing is broken and no one is injured.  Also, having security measures in place such as an alarm or fence around the pool can help keep accidents from happening and allow you to enjoy the pool.

When to Call a Professional

Call a professional when the job seems to be too cumbersome or advanced for you.  Time is money and you also want to make sure that the issue is taken care of properly. Professionals can diagnose and refer someone to you to help in your situation.

We also recommend the pool system be evaluated and serviced yearly by a pool professional or inspector during an annual home maintenance inspection


Swimming pools can be maintained easily but sometimes things do happen that need someone with more expertise.  If you have tried the steps above and no luck or need assistance, please leave us a reply below with your question!