air leak repair

sdtfp

Gold Supporter
Jun 4, 2020
172
NYC
Pool Size
17500
Surface
Plaster
Chlorine
Liquid Chlorine
Looks like I have an air leak in my system even though on my opening thread, opening 2025 I mentioned things went smoothly. I just checked and while everything looks good (except the psi) when the pump is running, once I stop the pump for a minute and then restart it, you can see air bubbles in the returns. So obviously air is getting into the system, when the pump is off.

I put my ear to the various possible leak locations when the pump is off and couldn't hear anything. I also put water on them and didn't see bubbles. Although maybe that's just for air leaking out like on a tire. This issue is air leaking in.

I have a bunch of possible leaks and want to get some advice on how to diagnose and fix the problem. I am going to try to attack the issue one by one from easiest to hardest.

1. I have a rubber plug on the waste output which is a threaded pipe. This is how it was when I inherited the system and I have been too naïve to fix it. I guess I have been relying to much on if its not broken then don't fix it. I don't know the sizing of this. Anyone can tell from the picture. My system is 1.5" pvc. This has threads in it.
2. Close of chlorinator holes. I asked previously here if anyone knew how to find plugs for these lines. No one has replied, so I will keep searching.
3. Lubing pump lid gasket.
4. I did lube up the drain plugs on the pump, but I will try reseating them.
5. replacing the pressure gauge and the assembly that connects it to the filter shell.
6. Resealing separation tank lid
7. reseating the plumbing line connections to the pump
8. reseating the water viewer on the multiport
9. Looking into the pipe that goes from multi port to separation tank. That has always had a small drip. It makes sense that would be the issue, except its worked fine like that in past years.
10. multiport maintenance.

I guess is this where I need a lot of help. What would you guys recommend. Should I call someone to do maintenance on it? I feel like if i tried that they would have no clue what to do or mess it up. Or should I buy a gasket and try to replace it myself? I saw a video on it and it looked hard. Or should I buy a new multi port and have someone install it or try installing myself? I need a plan of attack that doesn't leave me without a pump for a few days, so cost may have to take a back seat.
 

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Last edited:
Does your pump prime and run with a full basket?
Are there any visible leaks?
Does you pool maintain water Level?

If the answers to Yes, No, and Yes. Then you are likely just fine.
When I move my multiport, with pump off for example, I get air too. I'm not going to rebuilt it until it fails.
 
Do you see air bubbles flowing continuously through the pump basket when the pump is running?

Don't buy ANYTHING yet!























































/
Hard to tell if what I am looking at is air bubbles or just water being brought into the pump too fast? But yes it does look like large air bubbles in the pump basket, but its always looked that way, even when I've had no issues. So I may not know what I'm seeing but at least I know what it looks like when it is working.

Regarding not buying anything..... I did find this thread about closing off the chlorinator line. Used the link in there to buy some 1/4" NPT nylon caps. Figure for 10 bux, its worth a try. Interestingly, the OP there mentioned having DE leak with this same setup. I am not sure if he is right, because that would mean I have always had DE leaks and I don't think that is true. I definitely clean out a lot of DE from the filter cells at the end of the season.
 
Do you see air bubbles flowing continuously through the pump basket when the pump is running?

Don't buy ANYTHING yet!























































/
Tried to upload a video.
 
Does your pump prime and run with a full basket?
Are there any visible leaks?
Does you pool maintain water Level?

If the answers to Yes, No, and Yes. Then you are likely just fine.
When I move my multiport, with pump off for example, I get air too. I'm not going to rebuilt it until it fails.
Yup, that's my answers.

I read the link you mentioned in your other post and wanted to make sure I understood. Air in the system is only from the suction side? So anything past the pump only will cause water leak? I dont think I get how that works. But I dont have any water leaks that I know of.

In that case, the one thing that stands out in my mind is the chlorinator line I have connected from suction line to the pump output line when I stopped using the chlorinator. I will hopefully get the plugs for that delivered in a few days.

Also the main thing that bothers me is DE leaking into the pool. Not sure if there are other issues with an air leak as my pump primes and runs just fine without any air leaks after a couple of minutes of running.
 
So if you have visible air bubbles (pump running) sloshing or flowing that you can see through the pump basket lid, you have a suction side leak(s)

The suction side of your system for this purpose is between the pump and the suction pipe coming out of the ground. I WOldL SUGGEST YOU NOT WORK ON ANYTHING else until you fix that leak.