I’m hoping that someone can help me troubleshoot an air leak. It’s driving me crazy and I can’t seem to get anywhere. Sorry I’m advance for the long post but I want to explain everything as best I can.
I actually started the season off with two problems. I was losing water, as well as sucking air. The water leak seems to have been coming from around the entrance to the skimmer. I re-sealed around it and have not noticed anymore water loss. But I can’t seem to pinpoint the air leak.
Here’s my setup -
Suction side:
side vacuum, skimmer/main drain (connected, two holes in skimmer)
On return side:
Two returns
Therapy jets
Fountain
Solar heating
Electric heater (I’ve since cut this out of the line in an attempt to eliminate some metal staining issues, but the photos were taken before bypassing the heater)
One light (never worked but haven’t replaced bulb)
Air leak details:
It started last season with a few bubbles coming from the farthest return jet and some more air in the strainer basket than normal. Over the course of the summer it got bad enough that I started losing some prime when vacuuming (I have a side suction port for a vacuum attachment).
Since I uncovered the pool this year I’ve been able to do some work to try and narrow it down. I did find a pretty substantial crack in the PVC right at the threaded connection to the spigot that’s used to help prime the pump, so that was obvious problem #1. Since I’d just replaced the inlet ball valves and really didn’t want to have to cut that whole section out and replace it again, I patched the crack with some epoxy and silicone caulk. That seems to have sealed everything up to the point that I’m able to vacuum now, but I still lose a *tiny* bit of prime by the time I’m finished.
I had put some Metal Magic in to get rid of the stains, and at first the bubbles seemed to clear up. I’m guessing that the residue that the MM created was enough to seal up whatever was leaking. I went a few rounds this way, and the leak would always come back when I dismantled the strainer basket and filter housing to clean the filter and empty the basket. It’s gotten to the point now though that I have bubbles no matter what, even though I don’t seem to be losing prime anymore.
What I’ve done to troubleshoot so far -
There are no visible cracks inside the skimmer, but I did epoxy around the edge of the connection between the skimmer and the pipe that leads to the pump just in case that was a factor.
I also thought there may be some wetness at the threaded union going into the filter housing at one point, but it’s not always there so it’s hard to tell if it’s an actual problem or not. If that connection isn’t ideal, that could explain the bubbles from the return. It could also explain why when I open the pressure release valve on the filter a decent amount of air comes out before any water starts to, but since it’s downstream of the pump it wouldn’t explain the bubbles in the strainer basket would it?
I’ve also replaced the o-ring on the filter housing, strainer lid o-ring, both drain plugs, and both union gaskets on the pump, and replaced the pressure release valve on the filter.
At the start of all this, I did notice some water leaking out of the top union on the pump (the one that goes from the pump to the filter), but replacing the gasket didn’t seem to help any. After replacing it, I still had some water seeping out, but when I took it all apart again I realized I’d over tightened it and torn the gasket, so I replaced them again and have played around with various levels of tightening. I haven’t noticed any more seeping, but still have the bubbles. I bought an o-ring kit that also came with the o-ring that goes between the two halves of the pump and the shaft seal, but I’ve not replaced these yet.
This is driving me crazy. Does anyone have any suggestions that I’ve not tried yet? I’m really hoping it’s not underground.... ?
Sorry for the super long post, but thank you in advance to anyone willing to help me figure this out!

I actually started the season off with two problems. I was losing water, as well as sucking air. The water leak seems to have been coming from around the entrance to the skimmer. I re-sealed around it and have not noticed anymore water loss. But I can’t seem to pinpoint the air leak.
Here’s my setup -
Suction side:
side vacuum, skimmer/main drain (connected, two holes in skimmer)
On return side:
Two returns
Therapy jets
Fountain
Solar heating
Electric heater (I’ve since cut this out of the line in an attempt to eliminate some metal staining issues, but the photos were taken before bypassing the heater)
One light (never worked but haven’t replaced bulb)
Air leak details:
It started last season with a few bubbles coming from the farthest return jet and some more air in the strainer basket than normal. Over the course of the summer it got bad enough that I started losing some prime when vacuuming (I have a side suction port for a vacuum attachment).
Since I uncovered the pool this year I’ve been able to do some work to try and narrow it down. I did find a pretty substantial crack in the PVC right at the threaded connection to the spigot that’s used to help prime the pump, so that was obvious problem #1. Since I’d just replaced the inlet ball valves and really didn’t want to have to cut that whole section out and replace it again, I patched the crack with some epoxy and silicone caulk. That seems to have sealed everything up to the point that I’m able to vacuum now, but I still lose a *tiny* bit of prime by the time I’m finished.
I had put some Metal Magic in to get rid of the stains, and at first the bubbles seemed to clear up. I’m guessing that the residue that the MM created was enough to seal up whatever was leaking. I went a few rounds this way, and the leak would always come back when I dismantled the strainer basket and filter housing to clean the filter and empty the basket. It’s gotten to the point now though that I have bubbles no matter what, even though I don’t seem to be losing prime anymore.
What I’ve done to troubleshoot so far -
There are no visible cracks inside the skimmer, but I did epoxy around the edge of the connection between the skimmer and the pipe that leads to the pump just in case that was a factor.
I also thought there may be some wetness at the threaded union going into the filter housing at one point, but it’s not always there so it’s hard to tell if it’s an actual problem or not. If that connection isn’t ideal, that could explain the bubbles from the return. It could also explain why when I open the pressure release valve on the filter a decent amount of air comes out before any water starts to, but since it’s downstream of the pump it wouldn’t explain the bubbles in the strainer basket would it?
I’ve also replaced the o-ring on the filter housing, strainer lid o-ring, both drain plugs, and both union gaskets on the pump, and replaced the pressure release valve on the filter.
At the start of all this, I did notice some water leaking out of the top union on the pump (the one that goes from the pump to the filter), but replacing the gasket didn’t seem to help any. After replacing it, I still had some water seeping out, but when I took it all apart again I realized I’d over tightened it and torn the gasket, so I replaced them again and have played around with various levels of tightening. I haven’t noticed any more seeping, but still have the bubbles. I bought an o-ring kit that also came with the o-ring that goes between the two halves of the pump and the shaft seal, but I’ve not replaced these yet.
This is driving me crazy. Does anyone have any suggestions that I’ve not tried yet? I’m really hoping it’s not underground.... ?
Sorry for the super long post, but thank you in advance to anyone willing to help me figure this out!


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