Removing a pool pump impeller can be frustrating if it is stuck and won’t come off. And when you’ve never taken an impeller off before, it’s hard to know if you’re doing the right thing.
It should be a fairly easy job. Or that’s what the instruction manuals will have you believe. But when it won’t unscrew, well, that’s when things get tough. Luckily, there are some tips and tricks for removing tight or seized impellers.
Here’s a quick summary of how to remove a stuck impeller.
To remove a pool pump impeller that is stuck on the shaft and will not unscrew, lock the motor shaft and use a strap wrench to take off the impeller. Failing this, you may need to remove the motor shaft and grip it in a vice to undo the impeller.
Why Won’t the Impeller Come Off
If you’re trying to replace your impeller or change a leaking pump shaft seal obviously the first thing you need to do is actually get the impeller off the motor shaft.
We’ll go through some basic reasons why you’re having trouble unscrewing and removing your pump impeller. Sometimes it’s as simple as overlooking a screw, whereas other times you may need to break the impeller to remove it.
And further below in the article, we have two guaranteed methods for getting the impeller off.
Unscrewing in the Wrong Direction
It may well be possible that you’re tightening the impeller and not loosening it. Pool pump impellers are removed by unscrewing them in an anti-clockwise direction. Make sure you’re turning it this way.
Impeller Locking Screw or Set Screw
Many impellers will not have a screw and should undo by turning them counter-clockwise. But other pumps will have an additional screw securing the impeller. If your pump has a screw, it will have one of the following types. The screw needs to be loosened before you can take the impeller off.
Impeller Locking Screw
You can sometimes find a screw on the side of the impeller. It will be near the center of the impeller near the shaft of the pump. It can be a screw or Allen-type bolt. Just undo it in the usual way.
After you’ve done this, you can unscrew the impeller in an anti-clockwise direction.
This screw is located in the center of the impeller. It needs to be removed before you can unscrew the impeller. Grab a screwdriver and turn the screw clockwise. Usually, the rule to undo screws is “lefty loosey and righty tighty”. But not with this screw. Undo it by turning it clockwise.
Now you should be able to loosen the impeller.
The threads on the impeller can get damaged. It can be tricky to take the impeller off if this happens. You’ll likely need to cut it or break it to get it off.
An oscillating tool may help you to cut it off. Careful not to damage the shaft though.
Sometimes the threads of the shaft will rust a little. When this happens, the impeller will seize onto the shaft. If you’ve tried everything else, you’ll need to cut the impeller off. Try using a multi-tool (oscillating tool) to do this. Be very careful not to cut into the shaft or threads though, as this could damage it beyond repair.
Related Reading: 12 Reasons Pool Pumps Leak (and How to Fix)
Impeller Was Jammed Up
When debris accumulates in an impeller and isn’t cleared out, it can be enough to stop the impeller from turning. If the impeller is jammed and the motor is still turning, this can further tighten the impeller, making it difficult to remove.
Follow the methods below to remove it.
Tools to Remove Stuck Pump Impellers
First of all, before you start, do NOT use channel grips (multi grips) or vice grips to remove your impeller. It’s made from plastic and you will crack it.
There are two tools that I recommend you use to remove and unscrew an impeller. These are:
- Specialized Impeller Remove Tool
- Strap Wrench
Whilst the specialized impeller removal tool will work, it’s really not necessary. They can be expensive ($50 or so) and can only be used for one purpose.
I recommend you use a strap wrench instead. This is the tool I used to get my tight impeller off. If you’ve never used a strap wrench, it’s a tool with a material or rubber strap which wraps around the object you wish to hold.
When choosing a strap wrench, I recommend you make sure the strap is long enough to fit over the impeller. You can either get one with a rubber strap or a material strap.
Two Methods to Remove Stuck Impellers
1. Removing an Impeller with a Strap Wrench
The strap wrench is your friend for removing tight impellers that will not unscrew by hand.
To use it, simply wrap the strap around the impeller. Make sure the strap is tight. Now you’ll need to stop the motor shaft from turning. Use a wrench or screwdriver at the end of the shaft.
Once the shaft is locked, use the strap wrench to loosen the impeller in a counter-clockwise direction. It might take a few goes to crack it, but once it starts moving, you can usually undo the rest without the wrench.
2. What to Do If the Pump Shaft Keeps Turning
When it comes to impeller removal, you’ll need to lock the motor shaft or stop it from spinning. This needs to be done at the same time as unscrewing the impeller.
Usually, there is a slot for a screwdriver or a bolt at the end of the motor which is, so you can lock the shaft and prevent it from spinning.
What if you can’t stop the shaft from turning? When I tried to remove the impeller from this pump, even with the strap wrench, I wasn’t able to stop the motor shaft from turning. It’s quite common that the shaft will slip. You’ll never get the impeller off if it does slip.
Luckily, there is a solution to stop the shaft from spinning.
You’ll need to remove the motor shaft from the motor. This is what I had to do. With the shaft removed, you can grip the shaft tightly, so it doesn’t slip. Then you’ll be able to remove the impeller.
Removing the Motor Shaft of a Pool Pump
This is what you need to do to get the impeller off your pump if the shaft keeps slipping or moving.
Although general in nature, the steps below are transferable to most types of pool pumps. Regardless of if you have a Hayward, Pentair, Onga, Davey, or Jandy the method below will be similar.
In some cases, there may be additional screws or steps.
Step One) Remove the screws and mark the position.
Before removing anything, take a sharpie or permanent marker and mark the position of the seal plate in relation to the pump housing. Also mark the motor mounting plate in relation to the motor and the seal plate. You want these to go back in the same positions.
Now you can undo the screws that attach the motor end plate to the seal plate (the part of the pump that has the impeller attached.
Some pumps will have through bolts like this.
Step Two) Separate the motor end plate. Using a screwdriver and hammer, tap around the join in the end plate to separate the motor from it.
Step Three) Pull out the motor shaft. With the bolts or screws undone, you should now be able to pull out the shaft. It can be a little tight to pull out but if you’ve undone all the screws, it should come undone.
When you do pull it out, the shaft will slide out of the motor. The impeller and seal plate will still be attached.
Note: with the Hayward Super Pump, you’ll need to remove the back cover of the motor, and then remove the motor governor before the shaft will come out.
Step Four) Remove the impeller with a strap wrench. With the shaft out, you should be able to get a proper grip on the shaft to hold it whilst you remove the impeller.
Use vice grips, channel grips (multi grips), or a vice to hold the pump shaft. Put the strap of the strap wrench around the impeller and turn the impeller in a counter-clockwise direction.
With any luck, the impeller should come off now.
Whilst you have the motor apart, I would recommend you replace the diffuser seal, pump housing seal, and shaft seal. You can buy generic shaft seals here.
Related Reading: How Do You Know If Pool Pump Shaft Seal Is Bad?
What to Do If these Methods Fail
If you’ve tried these methods and still can’t unscrew the pump impeller, it’s probably seized on. You’ll need to cut it and break it off. A pool pump impeller is made of a plastic composite material and is easy to cut.
If you’ve removed the motor shaft, you can cut it with a hacksaw or oscillating tool. Use an oscillating tool if you haven’t fully removed the motor shaft and can’t get to the impeller with a hacksaw.
Warning: Go very easy and slowly when cutting. You do not want to cut into the pump motor shaft or the threads. This could ruin your pump.