Vacuum losing suction

JimmyGee

Member
Jun 16, 2022
6
Long Island, NY
20x40 IG vinyl liner 36,000 gallon 20+ year old pool. Had a number of issues this year opening the pool (plus some vacation travel) and my pool is just about ready, but needs a good vacuum. Once connected, the vacuum will lose its head.

Replaced the pump motor with an exact replacement (1.5hp). Rebuilt the pump. Purchased a new vacuum hose. Still no luck. When the vacuum hose is disconnected from the skimmer, or suction side is diverted to the bottom drain, all works as it should.

I am getting a little air entering at the skimmer cuff - wrapped it with stretch wrap - but to no avail. I’m now adding water to raise the level above the top of the cuff and will try again. In the meantime - any other suggestions?
 

Rancho Cost-a-Lotta

Silver Supporter
TFP Guide
Apr 10, 2018
3,699
Rancho Cucamonga, CA
Pool Size
18375
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
CircuPool RJ-45
I’m now adding water to raise the level above the top of the cuff and will try again.
I bet stopping the air leak will solve your problem. Are you connecting the hose to an adapter plate or directly to a suction port at the bottom of the skimmer?
 

JimmyGee

Member
Jun 16, 2022
6
Long Island, NY
Yes, air. From somewhere. Added water to the pool so the skimmer was practically full. All seems fine with suction at the bottom drain or the skimmer (though when I open the bleed valve at the top of the filter there is a surprising amount of air coming out). As soon as I connect the vacuum I lose the head. The hose is brand new (swivel connected to vacuum). There is a small leak at the shaft seal of the pump, but since it’s leaking water (pressure side?) I don’t think that’s it. There’s one connection between the pool piping and the pump. I’ve wrapped it with stretch wrap as a precaution. 20+ years I’ve never had this happen. I did replace the pump motor this year - it’s almost as if it’s powerful enough to run the system under normal circumstances - but the additional force to pull water thru the 48’ hose is more than the pump can handle, even if I try to vacuum to waste (it’s a Century 1-1/2 hp motor C48L2N134C1, which is what it replaced). My next step is to replace the shaft seal - needs to be done anyway - but I am at a complete loss. Appreciate any/all suggestions.