Cavitation caused by poor intake design?
- Thread starter FernTheBrute
- Start date
So here's an updated sound clip after getting rid of the 90° right at the intake of the pump. Much less gravelly, but it makes a intermittent suction-kite sound. There's no air in the pump basket or bubbles at the return and the shaving cream test on all suction side seals yielded no results.
- May 3, 2007
- 18,071
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
When you shut off the pump, does the filter gauge go to zero?
Do you have a suction gauge you can put on the pump basket drain plug?
Removing the wet end from the motor should be fairly straight forward:
Do you have a suction gauge you can put on the pump basket drain plug?
Removing the wet end from the motor should be fairly straight forward:
Yes it does
No I don't have one
You overestimate me
That said, the sound got much, much quieter today as the temperature warmed. I'm wondering if some thermal expansion might have almost sealed some kind of hidden leak, maybe on one of the two drain holes,which would show as bubbles in the strainer.
- May 3, 2007
- 18,071
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
You might just try lubing both the pump lid and drain plug gaskets. I know you said you did not see any air but when it enters the pump basket at the bottom, you may not see it.
Not much success :/
I've tried something else tho. When cleaning the basket in my skimmer, I put a finger in the valve to restrict slightly the water flow to the pump. The noise got much worse, as if the pump was starved for water.
I then decide to try the opposite : I closed half of my return eye with a finger. This obviously increased the pressure at the filter from about 16 psi to around 20, but it also almost completely stopped the gurgling sound of the pump.
I'm beginning to think the valve under my skimmer might be starving the pump of sufficient water for its power?
I've tried 50/50 bottom drain and skimmer, bottom drain only and skimmer only. Same results, so I don't think my drain is blocked and I know my pipe from the skimmer to the pump isn't.
- May 3, 2007
- 18,071
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
50/50 is actually both valves fully open. But they both go through an single exit hole to the pump as big as each port itself.
Well, maybe my problem isn't on the suction side.. Had to do a long backwash and I realized the pump is dead silent when doing so (and bypassing the filtration system). I'll try to see how I can improve the flow from the filter to the heater and back to the pool, there are a few funky connections.