Bubbles in pump basket

[jkapp]

I have four pipes each with a Jandy Neverlube valve coming into the suction side of my pump (spa, main drain, and 2 skimmers). While the pump is running, if I close off one or two of the suction side valves (thereby increasing the vacuum pressure), I get a burst of bubbles in my pump basket. Is this normal or does it indicate that I have a minor leak on the suction side somewhere?

I just want to get your thoughts before I start re-taping threads and pulling apart valves. I already checked and lubed the gaskets on the pump lid and drain plugs. I did notice that my 2-port Jandy Neverlube valves appear to be installed backwards. One port says "IN", but that port on the pump side of the valve. Could that contribute to the bubbles? It appears that I can just remove the six screws on top of the valve and turn it around.

Thanks for your help!

 

[JasonLion]

That sounds like air coming out of solution because of the low pressure in the pump strainer basket. If you had a real air leak there would be some bubbles in the pump basket all the time when the valves were open.

 

[jkapp]

I think I may always have a little air passing through my pump, but there are only a couple of instances where it is apparent. Normally, with my pump running on high speed, there is enough flow through the pump basket to draw bubbles through the pump and keep the top glass clear.

I've recently upgraded to a 2-speed motor. If I run on on high-speed to get all of the air out of the basket and then switch to low-speed speed, after a few minutes I'll see a couple of tiny bubbles on the pump cover glass. After an hour, I'll have a bubble about the size of a quarter. After a day, I have about an eighth to a quarter of an inch of air in the top of the pump basket.

My solution right now is to run the pump on high speed for 15 minutes per day to wash the air out of the basket, but I'd rather not have to do that.

 

[Bama Rambler]

Have you lubed the o-ring on the strainer basket?

 

[jkapp]

Have you lubed the o-ring on the strainer basket?

Yes - I've lubed the pump basket lid o-ring and the o-rings on the drain plugs. I've also pulled apart the inlet and outlet unions on the pump and lubed the o-rings inside of the unions.

I spent some time staring into the pump lid tonight to see if I could see where the bubbles were coming from. What may be happening is that tiny bubbles are forming on the pump lid glass and these combine to become larger and larger bubbles. As Jason suggested, is it possible that the low pressure created on the suction side of the pump is air to come out of solution? And after a day or two this builds up to be a significant amount of air.