Swimming Pool Air Leak

[Solittle]

We have a 33 year old in ground pool. Several weeks ago we started getting rather large air bubbles coming out of one of the return line outlets about every 30 seconds (=/-). This tells me the leak is in the suction side of the system. I Googled "swimming pool air leaks" and one of the suggestions was to buy a "drain king", turn the pump off and use the drain king to pressurize the suction side of the system through the skimmer. Hopefully this would would force water out where the leak is.

Has anyone done this, any tips or other ideas?

 

[mudmagnet63]

Re: Swimming Pool Air Leak

Solittle I worked as a pool tech for 13 years. The first thing to look for is bubbles in the pump pot ( clear lid ) are there bubbles?
NO. it will be a gasket in between the pot and impeller housing
Yes. The most likley spot would be the male adaptor screwed into the front of the pump or a lid gasket. take a water hose and run over the suspected areas ( lid & male adaptor. ) if the bubbles decrease refine your search area. check the drain plugs on the pump. Valves are a prime source. the water hose will tell you alot use your hands to pool water around suspest areas. When you run the water over a leak the bubbles will almost disappear.

Make and model of pump would help Discription of any valves on the suction side

 

[eurolarva]

Re: Swimming Pool Air Leak

Not an expert here but I had this with my pool. Valley Pool said it is the high pressure end before the pump. In my case there was not enough water in the system when the pump came on and overheated the pump which melted where the pvc plugs into the pump. I like mudmagnets way of checking using a garden hose. Good luck

 

[Solittle]

Re: Swimming Pool Air Leak

Mr. Mud - The pump itself is a Sta-Right (or Rite) and is all brass including the cover over the basket on the suction side (so I can't see bubbles). The motor is new - as in yesterday - but the air leak has been there for a good while. At this point I suspect the o ring that seal in the cover over the basket in the pump. I will try to test tomorrow but in any case wil get a new o ring.

In looking at again I have my doubts that the drain king thing would aid in the troubleshooting as there seems no way to close off both the skimmer and main drain ( without draining the pool to get to the main drain) - hence no or little pressure to show the leak.

 

[mudmagnet63]

Re: Swimming Pool Air Leak

An all brass starite is probably one of the best pumps ever made, when the pump is running and then switched off if water squirts out of somewhere on the suction side due to the backpressure of the filter or starts to drip immediately look there first.

 

[rob711]

Re: Swimming Pool Air Leak

its going to suck in air from the front of the pump or the lid...like mud said turn the pump on and off and watch for water squirting out...do u vacum through your skimmer? if u do and u notice its not working as it used to then it could be a fitting under the skimmer..i too was a pool guy for a while..running a hose over all the connections on the front of the pump.including any valves is how i found the majority of suction leaks...are u losing water.

 

[Solittle]

Re: Swimming Pool Air Leak

I detected a small amount of water comming from either the lid over the basket next to the PVC fitting that comes out of the top of the pump or where the PVC fitting goes into the top of the pump. I would not think water could come out of an air leak due to suction but I will replace the o ring in the lid and if that does not do it I will try the other methods suggested.

I have two large brass gate valves - one for the skimmer & one for the main drain. I tested them by turning one off then the other with no change in the air leak. I guess I can rule them out.

And also I am not loosing water in the pool.

Thanks to all.

 

[mudmagnet63]

Re: Swimming Pool Air Leak

With a brass pump it will be hard for you to find the suction leak because u cannot see the reduction of air in the pump pot, so keep that in mind. Water will not come out while the pump is running only when u shut it off and backpressure from the filter pushes it back

 

[eurolarva]

Re: Swimming Pool Air Leak

The worst part of your problem is the water looks cloudy all the time. I am betting on the fitting from both the skimmer and main drain that connects to the pump.

 

[Solittle]

Re: Swimming Pool Air Leak

I think I found it but will need another day to confirm. I replaced the o ring (part #16 in above) and the air leak seems to have stopped. Thanks to all for your input.

Do you have any tips for adjusting the impeller? It may be called head space - not sure of nomenclature on that - anyway it would be the distance between the impeller and the body of the pump. I think the distance is critical to get the correct pressure without binding on the body of the pump. On mine the impeller is held on the motor shaft by 3 allen screws. I installed a new motor Saturday and now have difficulty in getting a prime so would suspect that the gap is too big.

 

[mudmagnet63]

Re: Swimming Pool Air Leak

No adjustment to impeller, trouble priming = suction leak

 

[Solittle]

Re: Swimming Pool Air Leak

The impeller itself cannot be adjusted as mudmagnet states but it's position on the motor shaft can and should be adjusted relative to the body of the pump. If the outer edge of the impeller is too far away from the face of the pump the water will cavitate and have little actual suction. If it is too close it may bind with the pump body.

I solved the priming problem by closing one of the two return valves. I opened it when I got a good water flow. There was no leak.

 

[ob]

Re: Swimming Pool Air Leak

My pool pump stays primed after shutting off for several days.Over the years my pump priming problems were either a failed seat on the sand fliter plug valve or a failed mechanical seal between the pump and motor.I've had to replace both a few times over the 22 years we've had our inground pool.

 

[ondarvr]

Re: Swimming Pool Air Leak

Wow, lots of pool guys here, I too was in the swimming pool industry, as a plant manager, we made many other items too, but started with pools. I also had my own company that did major renovation on resort and hotel pool complexes. I still have too much pool stuff around, boxes and boxes of pump, heater, and filter parts, I just give the stuff away, but the boxes never seem to empty out.