Intermittent pump flow

[no fence cl pool]

our 15x30 oval has 3 return jets fed by a single pump (it's slightly oversize in h.p. I think and I'll post model later, but it's not unlike the below picture, but in tan)
http://img2.wfrcdn.com/lf/49/hash/17571 ... d-Pool.jpg

We're all algae'd up. We need to keep up on cleaning, but we've shocked it a few times and I'm thinking the "basics" are failing somewhere.

The filter is an S244T2. I checked the sand level and it was below half. Some does spill out to the front where the backwash feeds. I've added sand since then; I suspected it was low enough that the backwash wasn't clearing out the muck or the filter wasn't pulling through a uniform level of sand thickness with it being below half. I was advised to run it a little lower than mfgr. recommended.

Back to the thread title. Pumping is stopping. I keep the o-rings lubed yearly and all are fine. No air bubbles are coming out of the return jets (unless I have switched from backwash to regular or had the valve off to fill sand or something like that.) And it's not losing prime that I can tell; I don't have to fill the filter basket before starting it up.

In fact, when it's not pumping, I can switch the timer off, then switch it back on and air bubbles come out, then normal pumping resumes.

Possible the pump is going out? Or do I need to idiot check myself and for leaks?

 

[Bama Rambler]

The fact that when you switch it back on air comes out means you have an air leak somewhere.
Are there bubbles in the pump basket when it quits pumping?
What is the filter pressure when it's pumping and when it stops?

 

[no fence cl pool]

Thank you for that first thought Bama. I'll get back to you on those 2 questions.

I'm familiar with soap bubbles in a pressurized system.
Other than a length of hose to the ear and passing the other end over all seams, any other how-to's on finding vac. leaks?

 

[Bama Rambler]

On pools it easy just run water over the plumbing and fittings until you see the bubbles in the pump basket lessen or stop.

 

[Richard320]

Coat the suspect area with shaving cream. It may do any of the following:

seal the leak - all the sudden no air in the strainer basket
get sucked in, and the void will show you where it's sucking air
shoot suds out the return, telling you the shaving cream is, in fact, getting drawn in somewhere

 

[no fence cl pool]

Thanks all. I never did get to the two questions provided by Bama.

But, the air bubbles went from unnoticeable to very noticeable. I snugged things up at the filter valve (one of those fine lessons in "what has last been changed should first be reviewed" when troubleshooting) and things seem good again.

The cleaning and getting cl stable are next for the weekend.