Pump is self-priming after being off for a few hours

[Bozer4]

Hello, I've noticed when my pump has been off for a few hours it seems to self-prime when starting up. I bleed off the air on the cartridge filter housing, but the air slowly gets back into the system after an hour or so. I've also noticed very small bubbles coming out of one of the return jets while the pump is running. I replaced the pump lid gasket but that didn't help. I'm thinking there's a very small leak somewhere on the suction side of the pump but not sure how to track that down, any suggestions would be appreciated. I don't see any water leaks. Also, when the pump shuts off it makes a little squeak noise, not sure if that's related.
Thanks, Brett

 

[Texas Splash]

I'm thinking there's a very small leak somewhere on the suction side of the pump but not sure how to track that down, any suggestions would be appreciated.

A strong possibility. Did you lube that O-ring under the pump clear lid? How about showing us some pics of your equipment pad? Might help us to see all the valves and lines going in to the pump. It is true that with some suction side leaks, you may not see a water leak.

 

[Texas Splash]

The TFP article just in case.

Suction Side Air Leaks

If you see air bubbles coming out of the return lines in your pool, you likely have a leak. Some signs that a suction side plumbing leak has occurred include: Read more

www.troublefreepool.com

 

[Bozer4]

A strong possibility. Did you lube that O-ring under the pump clear lid? How about showing us some pics of your equipment pad? Might help us to see all the valves and lines going in to the pump. It is true that with some suction side leaks, you may not see a water leak.

I lubed up the O-ring with some silicone grease, it's worth a try. I ran it for a little while and shut it off. I'll try running it again in a few hours and see if air is present under the clear lid and if it tries to self-prime. See pics of pad, the water on the pad is from bleeding the air out of the top of the filter housing.

 

[Texas Splash]

Looks straight forward. I would check that union nut in front of the pump. You might be pulling in air at the threads.