The pump is the heart of your pool's plumbing system. It circulates the water in your pool to move the chemicals that fight algae and bacteria and keeps things sanitized and clean. Unfortunately, pool pump leaks are common, and knowing when to call a professional is important for your time and wallet. Three of the most common places to experience a pool pump leak are on the suction side, on the pressure side, and on the shaft seal.
On the suction side, you can bet that any leaks will be air leaks. This means air is being sucked into the system. While it may feel intimidating to inspect the entire system, there are several likely places to inspect first.
If your pump strainer isn't properly sealed, the strainer cover will allow air in. One way to discover if you have a leak here is to slowly pour water over the lid. If this decreases the air within the basket, you have found at least one leak. You may be able to get by with cleaning and lubricating the o-ring but if it looks worn, it should be replaced and checking the lid for cracks.
Cracked PVC and Valves: Another common place for air leaks in your pool pump is your plumbing connections and valves. Over time cracks can develop here - to test this, you can try pouring water over this also. Even if a valve is intact, it might still need a replacement seal.
Low Water Level: Possibly one of the most common reasons for an air leak, low water levels allow for air to enter the skimmer. This is easily addressed by adding water to the pool. Another thing to look for here is a stuck skimmer weir.
Strainer Basket Drain Plug: The strainer basket drain plug can let air in if the o-ring is bad. Be sure to inspect it for wear and tear and replace it if needed.
If debris damages the impeller, spins on the motor shaft, or simply gets worn out from long use, this can be a source of your water leak. Another source is the housing o-ring or gasket. If water is leaking from where the pump housing and motor meet, be sure to check for a worn seal.
If ignored, an undetected shaft seal leak can create further damage to the pump itself and can lead to the replacement of the pump or motor components. A common cause of this leak is replacing the motor but failing to replace the shaft seal at the same time. Do not reuse the old seal. As much as we love DIY projects, something like this requires the help of a pool professional.

The Suction Side: Pool Pump Leaks - Knowing When To Call A Professional
On the suction side, you can bet that any leaks will be air leaks. This means air is being sucked into the system. While it may feel intimidating to inspect the entire system, there are several likely places to inspect first.Pump Strainer Lid
A leak is common in a pump if it is not completely sealed. Signs that you may have a leak here include:- The pump is struggling to move water
- The power is on, and nothing happens
- Pool water is cloudy
- The pump needs to be resealed with water and restarted more than usual to get going
- The flow rate is lower due to the air infiltration at the pump
- Skimmer baskets are floating
- The filter tank pressure is lower
- The pipe may be able to be wiggled or feels loose
If your pump strainer isn't properly sealed, the strainer cover will allow air in. One way to discover if you have a leak here is to slowly pour water over the lid. If this decreases the air within the basket, you have found at least one leak. You may be able to get by with cleaning and lubricating the o-ring but if it looks worn, it should be replaced and checking the lid for cracks.
Additional Locations Prone To Leaks On The Suction Side
Cracked PVC and Valves: Another common place for air leaks in your pool pump is your plumbing connections and valves. Over time cracks can develop here - to test this, you can try pouring water over this also. Even if a valve is intact, it might still need a replacement seal.
Low Water Level: Possibly one of the most common reasons for an air leak, low water levels allow for air to enter the skimmer. This is easily addressed by adding water to the pool. Another thing to look for here is a stuck skimmer weir.
Strainer Basket Drain Plug: The strainer basket drain plug can let air in if the o-ring is bad. Be sure to inspect it for wear and tear and replace it if needed.
Pressure Side Leaks
Since this part of the system is constantly under pressure, water will be forced out of any compromised area. Signs of a leak on the pressure side leaks include:- Water drips or sprays at the pipe connection to the pump
- You may notice a puddle of water under the pump, possibly creating damage to equipment in the area or even the pump itself
- Water damage to the surrounding areas
If debris damages the impeller, spins on the motor shaft, or simply gets worn out from long use, this can be a source of your water leak. Another source is the housing o-ring or gasket. If water is leaking from where the pump housing and motor meet, be sure to check for a worn seal.
Shaft Seal Leak
Between the pump motor and the impeller is the shaft seal that keeps water out of the motor. A common cause for a leak here is motor failure so it's crucial to address this quickly. When it comes to pool pump leaks - knowing when to call a professional is crucial. Signs you have a shaft seal leak include:- A puddle of water under the center of the pump below the motor connection point
- Water damage to the surrounding area
- Unusual, noticeable noise coming from the motor - indicative of a bearing motor problem
If ignored, an undetected shaft seal leak can create further damage to the pump itself and can lead to the replacement of the pump or motor components. A common cause of this leak is replacing the motor but failing to replace the shaft seal at the same time. Do not reuse the old seal. As much as we love DIY projects, something like this requires the help of a pool professional.