Pump Loses Prime Overnight

[cholmes28]

I have an inground pool which is losing prime overnight. If I turn off pump, I see a single air bubble form every 5 seconds or so in the filter basket housing of the pump. I went through the following steps to try and isolate the issue..

1. Skimmer/Drain closed, multiport on "closed" - no air leak

2. Skimmer/Drain closed, multiport on "filter" - air leak

3. Skimmer open, Drain closed, multiport on "closed" - air leak (I can hear air moving in the multiport)

4. Skimmer closed. Drain open, multiport on "closed" - air leak (I can hear air moving in the multipart)

5. Skimmer open. Drain open, multiport on "closed" - air leak (I can hear air moving in the multipart)

I already sprayed soapy water on everything, and was not able to see any bubbles get sucked into anything.

The above steps lead me to believe there is an issue with the multiport, like perhaps the spider gasket. The one thing that has me confused is why on #2, do I not hear any air moving in the multiport even though I still have the air leak? Only thing I can think of is that when the skimmer or drain is open in #3 or #4, there is more of a vacuum which sucks more air, and thus I can hear it. Thoughts on my theory? Should I try replacing the spider gasket?

[Pool Clown]

Do you have a Sta-Rite pump? There is a small plug at the bottom of the pump pot. that plug has an o-ring. That oring cracks after only a few years. This could be your leak.

[cholmes28]

It is a Hayward Super Pump, but there are 2 drain plugs - one on the side, and one toward the bottom of the side that has the suction. I sprayed soapy water on them both, and didn't see any bubbles get sucked in, but I will check that. The leak only started after my pool guy opened the pool after it had been closed for the winter. I know that he took those drain plugs out for the winter, so maybe when he put them back, he left out the o-ring or something. I will check that, but if that is OK, then I am thinking about replacing the spider gasket on the multi-port.

[cholmes28]

Problem Resolved!!

I removed the 2 drain plugs on the pump housing, and noticed that there was no o-ring. I bought 2 new plugs with o-rings, screwed them in, and ran through all the scenarios, and there is no air leak as of yet. I had long suspected that since the issue started the day after the pool guy opened the pool in the spring, that it may have been caused by something one does when they shut down a pool. He probably stripped the threads screwing in one of the plugs or something.

[need-for-speed]

 

Problem Resolved!!I removed the 2 drain plugs on the pump housing, and noticed that there was no o-ring. I bought 2 new plugs with o-rings, screwed them in, and ran through all the scenarios, and there is no air leak as of yet. I had long suspected that since the issue started the day after the pool guy opened the pool in the spring, that it may have been caused by something one does when they shut down a pool. He probably stripped the threads screwing in one of the plugs or something.

 

Great news!

I have often found that detective work can be more important than mechanical skills......even when working on cars, plumbing, etc.

Good job !