Troubleshooting air in lines and pump "straining"

[Rq120]

This morning pool seemed to be working fine but there was air in the return jets (only the closest one).

I checked my skimmer. It was ok and full
I turned off the solar to make sure it wasn't a check valve there. Still bubbles.
I bypassed the heater - still bubbles.
So as next step I turned off the SWG to make sure it wasn't a byproduct of that (although seemed more bubbles than I would expect from SWG). - still bubbles.

However, (and here is where the troubleshooting comes in) at this point we notice strange behavior. The pump now seems to be pulling inconsistently. The skimmer will suck well and then you can see the suction drop off. Also, if you are listening to the pipes you can hear air come in bursts. Mean it will be quiet then gurgling, then quiet then gurgling.
Seems that we exacerbated the issue by bypassing some of the extra pipe?

Could all of that be from an air leak? Or do we troubleshoot something else. I checked the pump basket just in case and there is nothing in there. Nothing has been sucked down the skimmer line that I know of.

Any next steps would be appreciated.

 

[Texas Splash]

I would check the following:
- Pool water level good; about halfway up the skimmer
- All valves in the proper/open positions
- Weir door at skimmer not stuck; operating properly
- Pump basket lid O-ring lubed nicely; drain plugs too for that matter
- Pump impeller not effected by debris; power OFF, check inside for easy movement of impeller with no debris
- Filter cleaned; many times a dirty filter can restrict water flow and cause odd behavior.

Let's start there and see what develops. Let us know.

 

[Rq120]

Thanks, I (re)checked all of that.

After cleaning my filter and restarting the system it sounded like air being sucked through the inline chlorinator. I lubed the o-ring and I didn't heard that noise any longer. I checked the skimmer with my hand with the basket out and it seems that the suction is consistent. Now the pump seems to be running consistent and the system as a whole is running well, I'm just getting constant bubbles out of the one jet. I'm assuming that means I have an air leak. What's the best way to find this leak?

 

[Texas Splash]

What's the best way to find this leak?

If everything else above checks-out good, then you do your best to check everything above ground on the suction side. Eliminate each thing one at a time. Sounds like you already took care of the Pump O-ring and drain plugs, so that leaves joints, check valves, and 3-way valves before the pump. Any of those can have a small O-ring or seal that can let air in. If all of that is ruled-out, you may want to check the suction line itself. It's not all that common for a suction line to get a crack, but it can happen.

Also, there have been reports of some pumps showing signs of wear this way as well. Not usually the first culprit, but it can happen. I mentioned the filter because that's exactly what happens to me when my cart gets dirty. Pressure goes up slightly, bump basket shows a little air gap at the top, and my #1 return jet in the line pushes bubbles.

 

[Rq120]

How do you test for an air leak? I was reading the forums and saw somewhere it mentioned foam shaving cream?

 

[Texas Splash]

How do you test for an air leak?

Fitting and joints above ground can be tested in various ways. Shaving cream is one, but a bit messy. You can run water over the joint, or also try seran wrap.