My wife and I purchased our house (made in 1962) about a year and a half ago as a foreclosure. The pool has been in pretty good shape, but the pump will suck air occasionally. I recently figured out that I think it's in the skimmer.
When run with no attachments, everything runs fine. When I have the automatic pool vac hose placed directly into the hold at the bottom of the skimmer, everything runs fine. When I use a skimmer plate to vacuum or when I use a Vac-Mate, the system sucks air. Since the Vac-Mate is see-through, I can see bubbles of air coming from the side. Water is not lost, though. It seems like when there is extra pressure on the skimmer, it pulls air through a crack. When I put dye in and the pump runs, it goes straight down the hole, as it should.
Trying to look through the Vac-Mate, I thought I identified roughly where the crack would be. I bought some epoxy putty and put it on the crack (it felt more like a scratch by feeling it, but everything else felt smooth). After letting it cure, I tried again, and the issue persists. I'm wondering if I didn't put enough putty or if I got the wrong spot. Does anyone have any ideas on how else to identify where a crack may be? I don't really want to spend the money to replace a skimmer when it's something (hopefully) small. Or if you have other ideas. Thanks, in advance!