Need to replace pump Impeller on A.O. Smith Century Centurion Pool & Spa Duty Switchless Pump

To get to the Impeller you need to remove a series of bolts, or a large clamp, that holds the two halves of the pump together. Once you do that, if their is a diffuser (housing that goes over the impeller), remove it. To remove the impeller, you need to lock the motor shaft. You can do this a couple different ways depending on the motor. There will either be a small cap that grants access to the motor shaft on the back of the motor, or you remove a larger housing that grants access to the wiring and other components in the back of the motor. If it's the small cap, then you can hold the shaft with a wrench. If it's the larger housing, then you can slip a wrench (probably 7/16") under the thermal overload switch and onto the shaft to lock it in place. Now you can unscrew the impeller. Check to see if the impeller has a screw in the center. If so remove this first. It will be reverse thread. The impeller should spin off counter clockwise. If the impeller is very tight, be careful not to damage it. If you don't have an impeller wrench, I strap wrench, or very large locking pliers with a rag around the impeller works well. Hope this helps. If you need further assistance post a reply in the comments, and don't hesitate to leave a good thumb rating if you found this helpful. Thanks, and good Luck!

I think my motor has the small cap, but it didn't turn with moderate force. Afraid to break it. Here is a picture of it. Should I just give it more force?