Union Leaking

[CT-Steven]

So, my pump "locked up" and I had to take apart the plumbing to remove the pump so I could fix it. When I put everything back together the pumps housing's union (connection from sand filter to pump) leaked like a sieve. I tried to tighten the union nut but just as it goes to tighten it slips on the threads loosening up again. I looked at the pump and union and the threads seem fine. So before I go and order a new Hayward union (Hayward SP1500 female) I wanted to see if anyone else had this issue (maybe a Hayward SP1500 male?), or they used a different part? Maybe one that has a better fitting? At the moment I had to revert back to the stock connectors, hose and clamps. Thankfully something told me to save it as a backup

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[1poolman1]

Before your pump "locked up," it likely overheated. That could cause the union to be deformed and, unfortunately, even the pump. Hopefully, all you need is a new union fitting.

 

[Texas Splash]

When the pump locked-up, did it overheat? I wondered if the union got hot and distorted a bit? If nothing obvious stands out, Maybe try about 3 wraps of Teflon tape on the threads before trying to screw the union back on?

 

[CT-Steven]

No, as I unplugged the pump to mow the grass, when I plugged it back in and turned it on it just hummed. The water is coming between the nut and the base plate, so I assume that the "O" ring is just not properly seating down hard enough. I can try the Teflon tape and see if that allows the nut to tighten sufficiently enough...

 

[1poolman1]

While the tape may allow you to tighten enough to get a seal, it will fail. Part of Teflon's allure is the fact that it is also a "lubricant" (allows pipes to be tightened easier) and will slip on itself and release. It is for sealing plumbing fittings (taking up space), not holding parts together. When it does you will lose a lot of water. If this was the suction side of the pump you might get away with it. On the pressure side it shouldn't be done.