When it does drain down, does the water level in the strainer basket go below the invert (bottom) of the suction inlet? On my pump, it will prime (in the sense of pumping water at least) if there’s any water in the strainer basket. Do they not all work that way? If so, seems to say the strainer basket is completely emptying (so it can’t prime) and I’m wondering if it’s the pump drain plug o-ring or a crack in the strainer housing that may be leaking?
 
Last edited:
Again, that is very likely due to the suction side air leak. Pump RUNNING, it continues to push air into the top of the filter (air from the suction side leak). When the pump stops, however, that air has pressurized the top of the filter, pushing the water backwards out through the pump.

Sorry, but the pool tech knows NOT about which he speaks! :mrgreen:
Yes indeed. This pool store has made me quite upset at times, but they are the only game in town. I had a sand dollar with a leak in it, they came out and replaced but reused the standpipe, laterals and multiport valve. They told my we should just use the old parts until they fail. Well, eventually they did fail so I opened the box with all the new parts and discovered the reason the went with the old parts. The new mulitport was a high flow 2” whereas my whole system is a regular flow 1-1/2”. When I called them on the carpet they admitted they were unable to get the right one. No offer to get me the correct one.
As for the suction side leak. I will get that done tomorrow. As for the mystery filter basket emptying when the pump is turned off, that’s going to be a lot more sleuthing. Went out this morning and the basket was full to the brim and when it turned on it immediately primed. Each day is a Crud shoot whether there will water in it or not.
 
When it does drain down, does the water level in the strainer basket go below the invert (bottom) of the suction inlet? On my pump, it will prime (in the sense of pumping water at least) if there’s any water in the strainer basket. Do they not all work that way? If so, seems to say the strainer basket is completely emptying (so it can’t prime) and I’m wondering if it’s the pump drain plug o-ring or a crack in the strainer housing that may be leaking?
Thanks. The pump is a Pentair superflo so it does not have drain plug. as soon as the pump is turned off all the water in the filter basket rushes out to just around the bottom of the intake to the basket. BUT, it does not happen every time. For instance I went out this morning and the filter basket was full to top of the lid! And it ran fine. It could do that for a week then the problem may return. Yesterday I turned off, the water rushed out, I primed it, turned it back on and five minutes later turned it off. The water level stayed at the top. From everything folks are telling me it can be from a suction side leak. On another thread it said that if the enough air builds up in the filter It can force the water back out the basket. But who knows. But I’m also questioning if my multiport valve has an issue. For now I just need to fix the air leak on the suction side And see if it goes away.
 
Does you pump look like in the attached .pdf?

Since you’ve been told the suction line passed pressure test (just hoping it was tested properly), it may make sense to first look for trouble at the few fittings that were likely not part of that test. On the diagram, drain plugs and o-rings (parts #10 & 11 there are two of each); everything in the union assembly (all parts in #24), everything in the lid (parts #4, 5, 6).
 

Attachments

  • SuperFlo_Pump.pdf
    78 KB · Views: 4
Does you pump look like in the attached .pdf?

Since you’ve been told the suction line passed pressure test (just hoping it was tested properly), it may make sense to first look for trouble at the few fittings that were likely not part of that test. On the diagram, drain plugs and o-rings (parts #10 & 11 there are two of each); everything in the union assembly (all parts in #24), everything in the lid (parts #4, 5, 6).
Does you pump look like in the attached .pdf?

Since you’ve been told the suction line passed pressure test (just hoping it was tested properly), it may make sense to first look for trouble at the few fittings that were likely not part of that test. On the diagram, drain plugs and o-rings (parts #10 & 11 there are two of each); everything in the union assembly (all parts in #24), everything in the lid (parts #4, 5, 6).
Thanks. I just received my strap wrench from Amazon and it worked perfectly. I was able to open everything up and the o-rings are in fairly bad shape. Thanks to you I was able to order them fast via Amazon. Hopefully that will be the fix.
 
  • Like
Reactions: SoDel
Thanks. I just received my strap wrench from Amazon and it worked perfectly. I was able to open everything up and the o-rings are in fairly bad shape. Thanks to you I was able to order them fast via Amazon. Hopefully that will be the fix.
well, replaced the o-rings, lubed them up beforehand. Still lots of air in the filter basket and pool. looked with a magnifier for any cracks in the filter basket and found none. Before the filter basket there is a diverter valve to turn off either of my two skimmer lines or blend them. The leak detection company tested each line from the skimmers to the diverter valve with air, while closed, and said the held full pressure. so I assumed the air leak was post that diverter valve.. ie the basket lid, the o-ring in the threaded coupler, the o-ring for the drain plug or a crack in the basket. I’m almost now thinking to replace the diverter valve. Is there any other explanation? I have been told it has to be on the suction side but is the ever possibility it is the o-ring on the pump output? The only last thought is these two kids did not really know what they were doing and I spent $300 on nothing. they did find my pool leak in the tanning bed and fixed it quite well. Also part of the cost was them driving an hour each way. Thanks
 
well, replaced the o-rings, lubed them up beforehand. Still lots of air in the filter basket and pool. looked with a magnifier for any cracks in the filter basket and found none. Before the filter basket there is a diverter valve to turn off either of my two skimmer lines or blend them. The leak detection company tested each line from the skimmers to the diverter valve with air, while closed, and said the held full pressure. so I assumed the air leak was post that diverter valve.. ie the basket lid, the o-ring in the threaded coupler, the o-ring for the drain plug or a crack in the basket. I’m almost now thinking to replace the diverter valve. Is there any other explanation? I have been told it has to be on the suction side but is the ever possibility it is the o-ring on the pump output? The only last thought is these two kids did not really know what they were doing and I spent $300 on nothing. they did find my pool leak in the tanning bed and fixed it quite well. Also part of the cost was them driving an hour each way. Thanks
Also when they tested they put the air bladder in the actual line. I don’t see any visual cracks in the skimmer baskets. Is there a way to test them. You think you would see bubble going in a crack if there was one at the skimmer. whatever it is, it is a lot of air. The leak company said that they are more then willing to come back and test it again. Of course they are for another $300.
 
Is there any other explanation?
The shaft seal on the superflow could be bad. Here is a recent thread with exactly that problem. A bad shaft seal will cause a suction side leak.

 
The shaft seal on the superflow could be bad. Here is a recent thread with exactly that problem. A bad shaft seal will cause a suction side leak.

Thank you so much!
 

Enjoying this content?

Support TFP with a donation.

Give Support
The shaft seal on the superflow could be bad. Here is a recent thread with exactly that problem. A bad shaft seal will cause a suction side leak.

this is the first mention of this. Everyone else says no it is never past the impeller on the pressure side. I have a few more tricks up my sleeve then it’s new pump time. I’m first trying to get a used pump to borrow from my pool store to test it out. My pump is over ten years old, which I am told by the pro’s is not that old. But it seems old to me. Half of it is all rusted out! We have looked at getting a new pool. There are so many issues it has. But were trying to hold off as long as possible. Even a $500 new pump is a heck of a lot less than a new pool. I could replumb the entire system for less than $1000
 
this is the first mention of this. Everyone else says no it is never past the impeller on the pressure side. I have a few more tricks up my sleeve then it’s new pump time. I’m first trying to get a used pump to borrow from my pool store to test it out. My pump is over ten years old, which I am told by the pro’s is not that old. But it seems old to me. Half of it is all rusted out! We have looked at getting a new pool. There are so many issues it has. But were trying to hold off as long as possible. Even a $500 new pump is a heck of a lot less than a new pool. I could replumb the entire system for less than $1000
Also my second problem on the pressure side and losing water for priming over night I’m addressing this week. Redoing a lot of the janky pressure side plumbing. But I was thinking that if it were the gasket at the impeller that would cause that as well. The odd thing still is some morning I come out and the basket is full and ready to prime, other mornings it’s empty. So weird. It started up and primed the previous three days. This morning nope. Empty.
 
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.