Just can't solve the last small air leak

[Pauls234]

I am a new pool owner - inherited a good size above ground pool with the house we just bought. It has been a long and iterative process to get everything up and running smoothly, but I got there thanks to a lot of help on this forum. Pump was leaking badly so I've replaced all of the gaskets and impeller and also replaced all of my hose couplings - the filter is about 12 feet from the pool because that is where the electricity is so I needed to couple the hoses to get the needed length.

So, after all of that, the pump basket just does not stay completely full after say a 10-15 hour period. It is not bad, still near the top, but clearly some air is getting in somewhere somehow and removing the lid to re-prime on a daily basis is a pain and messy! I've checked and tightened all of the fittings numerous times and do not see any problems there. No water spurts anywhere when I turn things off either. I have noticed a very slow and inconsistent drip that might be originating behind the impeller - is it possible this is causing the air to get into the system and perhaps that gasket is not seated just right?

Also the pump at times creates a whirlpool effect in the skimmer and sucks some air. The water level in the skimmer stays high, it is just a very thin whirlpool that gets created in the center and will go down to the skimmer basket (again with the rest of the level still high) with a very obnoxious sucking sound. Putting a small stone in there solves this problem so I don't think this is the source of my air intake but I have to think there is something else at work here, any thoughts? Pump too strong maybe? It is a 2HP, pool is about 20,000 gallons.

Finally, given the distance from the pool would I be better off replumbing the whole thing with PVC or something better than the flex hose from the pool store? Do you think that may solve my air leak problem? I am wanting to make improvements for the long term, but for now I am just interested in not ruining things this summer.

 

[duraleigh]

If there is a vortex in the skimmer, that is a prime suspect.

Why did you take the stone out? Why do you think that's not the problem?

Do whatever you need to do to stop that vortex and see if that doesn't fix it.

 

[Pauls234]

Duraleigh - I have not taken the stone out, leaving it in solves the whirlpool problem, was just curious if this is suggestive of a deeper issue that I need to resolve.

 

[Pauls234]

Bump

Any thoughts/suggestions from anyone?

 

[duraleigh]

I guess I am missing something. The issue is apparently solved and it was the whirlpool. What other deeper issue are you thinking there might be?

 

[Pauls234]

Dave,

Sorry, the whirlpool was a separate issue, with the stone in and no whirlpool for the past several weeks (or I guess vortex is the proper term) I am still getting small amounts of air in the system and cannot figure out where it might be coming from.

I only mentioned the vortex because I was wondering what the cause of that might be.

 

[duraleigh]

OK, no more vortex but you still suck in air. Simply put, (and you know this already) you are sucking in air somewhere between the skimmer and the pump. Did you check the pump drain plug(s)? The most common place is the O-ring on the pump basket lid.

I am still having a hard time understanding your need to prime an AG pool. The pump is below the surface of the pool water, correct?

 

[Pauls234]

You know, I wasn't even aware a pump drain plug exists so that is not something I have looked for but will do so when I get home this eve. The o-ring is brand new and also has been lubed and visually appears to seal so I think that is ok.

When I say I need to prime, that is not exactly correct. What I mean is that a small air pocket slowly builds and appears at the top of the pump basket lid. The only way to get this out is to remove the lid (which takes some muscle given the pressure) and let the water (and air pocket) slosh out and then force the lid back on so I get a fresh clean start. This process of removing the lid so the basket fills with water is what I mean by "priming".

 

[duraleigh]

The only way to get this out is to remove the lid (which takes some muscle given the pressure) and let the water (and air pocket) slosh out and then force the lid back on so I get a fresh clean start. This process of removing the lid so the basket fills with water is what I mean by "priming".

What happens if you shut the pump off for a few hours...doesn't the pump basket stay full of water? (or refill itself?)

 

[Pauls234]

Yes, it stays mostly full, but that air pocket that forms over time on the under side of the lid does not go away unless I remove the lid, let water slosh out, and then put it back on.

Another data point that may be useful: after running the pump all day, the release valve on the filter takes about 20 seconds to begin shooting water. If I do this after say 30 minutes water appears almost instantly, after 2 hours, maybe a few seconds, so there definitely seems to be a slow build. But, bleeding the system that way still does not clear the pocket that forms under the basket lid.

Heading home shortly and I will look for a drain plug on the pump. Appreciate all the help and patience!

 

[duraleigh]

I have a clear picture now. Same diagnosis...suction side air leak but you knew that.

I have noticed a very slow and inconsistent drip that might be originating behind the impeller

Does it stop dripping when you run the pump? If so, it is probably sucking air. Well, you have the basic idea and know how to look for it. It's there and, being methodical, you can find it.

 

[Pauls234]

Dave,

ok, so after work with the pump running all day I went out for a peak and the water level in the pump basket was pretty low. As you suggested I looked for a drain plug on the pump and found it (again this was all equipment that came with the house and I believe was left outside for 2 consecutive Chicago winters). Took a screwdriver to it and it turned quite easily about 2.5 times, though there was no visible leakage, but it certainly needed tightening. The other odd thing was that I noticed some water forming underneath the head for the first time. I took a socket wrench and every one of the screws on the head was loose! There is no way that they have all been this loose for the past month as I cranked them pretty well when I replaced all the gaskets. So, tightened all of those, pump has been running for 15 hours now and there is zero air in the system!

Question: Is it possible that the vibration of the pump causes the head screws to chronically loosen? I just cannot think of any other plausible explanation and I suppose I will get my answer when I check them again in a few weeks.

 

[Bama Rambler]

With the loosened bolts. It could have been that the housing halves "settled in" after you reassembled it and that may never happen again.

 

[Pauls234]

Thanks Bama, that is a good thought.

Just to close this topic off... I was poking around the pool shed to see what else was left behind and I came across a plastic piece with a chunk of foam in it. Then I remembered another thread on here where someone was also getting the vortex turbulence in the skimmer basket due to not having a skimmer door. Then it hit me, I didn't have one either and I am supposed to. I popped the door in place and all of my problems are now solved! I think this was the root of many of my suction side airleak issues I have been experiencing since I bought the house. Pump has now run for 2+ days continuously and there is zero air in the system. Thanks again for all the help.

 

[Bama Rambler]

Thanks for posting this. It reinforces just how important that thing is!