How to get impeller off of shaft if it's not unscrewing

Reverse clockwise. Make sure to replace the shaft seal when you change the impeller, or else it will leak 99% of the time. You need to stop the shaft from moving to turn the impeller. See video, impellers and shaft seals are the same how to get to the shaft in the back is not so hopefully its exposed in the back and you don't have to take it all apart.

Open up the pump housing, by separating it into 2. Reveal the impeller. If there is a center screw in the middle of the opening of the impeller, it will normally be backwards threads. Remove that.
know if the impeller should unscrew off of the motors shaft, that will be normal threads. But, to do that, you will have to lock the shaft from spinning. Remove opposite side Cap on the motor, to reveal the shaft. Either use a wrench or flat blade screwdriver to lock the shaft. Now unthread the impeller from the motors shaft.

No. Do not try to unscrew the impeller! If yours is a housing with motor attached just grab the part that has the O-ring and pull it straight out. Though you may need to kind of wiggle it as you pull. Do it over a sink, the liquid in the housing is gray water and can be dumped. The impeller shaft cannot be bent and impeller must be firmly attached to the shaft. If it is bent or loose on the shaft it will not pump properly. If it's solid and straight it should work. Put some petroleum jelly on the O-ring before reassembly. I also like to coat the threads of the filter cap befor screwing it into place.

Take the screws off the outer cover fo the wet end. That will expose the impeller.
At the other end of the pump is a small metal cap in the middle. Pry that off with a screwdriver. That reveals the shaft of the motor which has a slot in it. This allows you to hold the shaft still with a large screwdriver.
While someone holds the shaft with a big screwdriver, you rotate the impeller counter clockwise to unscrew it off the motor shaft.
In my case the impeller was so caked onto the shaft with rust that we could not loosen it. We broke the impeller and still could not unscrew it. The screwdriver keeps jumping out of the slot in the shaft.
So the next step was to take the shaft out of the motor. On the far end of the motor are 4 small looking bolt heads. Undo those. They go right through the motor into the 4 legs of the wet end.
Stand the motor up with the wet end up. Pull hard to pull the wet end motor cover off the motor and you will then have the wet end and armature of the motor in your hands. Heavy.
Place some wood into a large vice and then grip the big silver part of the armature in the vice. Then unscrew the impeller.

Remove diffuser. Remove rear cover from motor. Hold shaft with either a screwdriver if shaft is slotted or 1/2" wrench if there is a flat on it. Unscrew diffuser. If there is a screw in center of impeller unscrew it first.(reverse thread)

Some impellers have a screw in the middle which screws into the centershaft with reverse threads. If it has one, unscrew that first. Next, there is either a flat on the shaft near the opposite end or there is a slot in the end of the shaft for a screwdriver. Hold the shaft securely, and unscrew impeller. Sometimes a big pair of pliers is needed, but be careful not to damage impeller.

First remove bolts holding motor to wet end. Pull motor back and out of wet end. Diffuser should just fall off. Not held by anything, there are just some locating tabs. Next, unscrew impeller. Some impellers may have a screw holding it on to center shaft. If so, unscrew.(Backwards thread). Remove back cover on motor and hold centershaft with large screwdriver or wrench on flat of shaft. Unscrew impeller. Next, unscrew 4 bolts holding motor to seal plate.

You will need to get access to the impeller, then unscrew it counter clockwise. You will have to hold the shaft of the motor to unscrew the impeller. You can gain access to the shaft by popping off a little round cover on the back of the motor, you should see a slot in the motor shaft. Once you get the impeller off, unscrew the thru-bolts. The housing should pull right off. From there you can pop out the seal half that is in the housing and replace it - the other half of the seal is on the impeller. These 2 pieces come with the new seal. When you put the housing seal half back in use some silicone around it. The impeller end just pushes on. Link to Aqua Flo XP2 Diagram

First, separate motor and pump. Remove back cover of motor. Drive shaft of motor either has a slot on end for a large screwdriver or a flat on it for a wrench.(usually 7/16) Hold shaft and unscrew impeller.