Pump stopped pumping

[New2water]

My pump was working fine until yesterday. It stopped pumping water without any change.
Symptoms:
Pump runs and there is a whirl action visible in the basket.
There is no pressure in the cartridge filter. No air comes out of the air bleed valve in the pressure gauge.
There is miniscule quantity of water flowing from the valve on the pump outlet. So it is not the filters possibly being clogged.
The strainer cover does not show water or air bubbling.

Troubleshooting steps I have taken include:
1- Cleaning the straining basket before the pump.
2- Tried various sources for inlet - spa, pool bottom, pool top, skimmer without any difference.
3- Tried various output options - spa, pool - no change.

Any ideas?
Thank you.

 

[Smykowski]

Classic symptoms of a clogged or broken impeller. You have to take it apart to get to the impeller, but the good news is, this may be a cheap/free fix.

 

[duraleigh]

When you turn the pump back off, is it still full of water? What happens to that "vivble swirl action" of water when you turn the pump on....where does that water go and what remains in the pump basket....air or water?

 

[New2water]

Followed the advice and opened the pump body. The impeller does not appear broken or clogged. Found two possible problems. The pump diffuser O ring is loose/worn out and was not sealing the diffuser against the pump body. Secondly, there was a glob of white silicon looking material in the body. It must have been there from earlier since it is too large to pass through the pump basket.
When I run the pump, water keeps swirling and what remains in the basket is both water and air. A little amount of water flows back to the hot tub where the output from the filter is directed. The pump is not pulling much water.
I have a second pump of the same model/size (Pentair Whisperflow WFE-4) for the waterfall. Should I move its diffuser and O ring to the defective pump?

 

[duraleigh]

YOur pump is not priming. I think you have a suction side air leak. Somewhere between the skimmer and the pump, air is being drawn into the system. Find that leak and the pump will prime.

 

[New2water]

Can't find the O ring locally so had to order it online. I will put the pump back together when I get the part, try to find the suction leak and report back. Thank you for your help.

 

[New2water]

Ultimately, it was the O ring in the cover of pump inlet basket that was not sealing. Replacing it with a new ring did the trick and the pump is now fully pumping.
Thank you all for your ideas and guidance.