Loss of Prime

[larcrow]

My pool pump (Sta-Rite Max-E-Pro P6EA) with an Integral Trap) has difficulty attaining the proper flow when it is started after being turned off overnight. The trap seems to lose water overnight and when it first comes on in the morning water starts to flow but at much reduced rate and just bubbles at the return in the pool. If I turn it off and then back on it does manage to start flowing although there are a tremendous amount of air bubbles for couple of minutes.
I’ve replaced the O-ring on the strainer lid and there are no apparent leaks around the pump. What are the other possibilities for a vacumn leak in this type of pump?

[czechmate]

Check the seals on the backwash valve as well. Drip around the handle would indicate a leak where you would loose the airtight system.

[larcrow]

Thanks, I don't have a backwash feature and there are no valves in my setup.

[mas985]

The pump drain plugs can also be a source of air leaks. Also, valves (the type that can be dissembled) can sometimes leak at the o-ring.

[CGPoolman]

If the pump basket is draining out - there's got to be a leak somewhere. Do you have any 3-way valves in front of your pump? These are a common source of air leaks. You could also check your pump lid for any small cracks.

Here's an easy way to test for any leaks in the suction line: When the pump has a full prime (or as close to full as you can get it) - turn the power off and on. If there is a crack in the pump lid, you should see the water squirt or bubble out when you turn the system off. Do the same thing and look at the 3 way valves (if you have them) and also take a look at the plumbing that goes right into the front of the pump. The valves have an o-ring the the top lid. If that o-ring is bad the valves can suck air while the pump is running and cause air to bubble out of the return jets. This can also cause the pump to lose prime when it is shut off.

-CG