Leak at the pvc coupling on the pump.

[rchadha]

Hi all,
Opened to a green pool this season. Also noticed that there’s a slight leak at the junction between the pump and the pvc coupling on it. Any suggestions on how to go about repairing? I have never repaired a joint like that before. Thanks in advance for your help.

 

[HermanTX]

That is a union. The bottom part is threaded into the pump. The nut should unscrew as it should be hand tight. With the pump off, unscrew that nut and try to push the pipe off of the pump. Your picture does not show what is above the pump going vertical so not sure how much flex is in that vertical pipe. There is a seal between the 2 halves of the union which the large nut keeps them pressed against the seal.

 

[rchadha]

Thank you Herman. It’s a rigid flex tube going to the filter. See attached. I can remove that and I’ll have enough room above it. Sounds like I can just twist remove the union? Is there a cement that holds that union to the pump? Or is it just an o ring?

 

[PoolStored]

Sounds like I can just twist remove the union?

Yes

Is there a cement that holds that union to the pump?

Likely not. No.

Or is it just an o ring?

o-ring in the union. I'd lubricate that with silicone lubricant (like magic lube II), don't use PTFE/Teflon lube.

 

[HermanTX]

The bottom half of the union should be screwed into the pump. There is normally an oring that seals it.
See this as example - Amazon.com

With flex pipe there should be some capability to move it. So turn off pump. Unscrew the nut and it should slide upwards on the top half of union. Push to one side and look for the seal that will be on either the bottom half or top half of the union. Ensure it does not have any cuts, lube it and reassemble.

 

[rchadha]

Yes

Likely not. No.

o-ring in the union. I'd lubricate that with silicone lubricant (like magic lube II), don't use PTFE/Teflon lube.

Thanks I’ll do this. Appreciate your help!

 

[rchadha]

So I took it out and there’s no o ring. Just pvc with tape, it looks like. I have tape to put it back together. Do you guys know what size o ring and where I can order it from? Thank you

 

[HermanTX]

So I took it out and there’s no o ring. Just pvc with tape, it looks like. I have tape to put it back together. Do you guys know what size o ring and where I can order it from? Thank you

If there is no oring then that fitting was designed for the interference fit when screwed together. I would put sealant on it and go back together.
For clarification, was the threaded piece into the pump leaking or was the union leaking? I was thinking it was the latter based on your picture.

Good info with this and look at the section on Assembling Threaded Parts.

PVC Repair - Further Reading

www.troublefreepool.com

 

[m a hanson]

So I took it out and there’s no o ring. Just pvc with tape, it looks like. I have tape to put it back together. Do you guys know what size o ring and where I can order it from? Thank you

That type doesn't have an O-ring. Normally theres a threaded female part and a screw on collar with the male side. There's an O-ring located on the female non moveable junction part. It appears you can just clean off the threaded end and reapply the teflon tape. Make sure you clean the female side to the pump too. Apply the teflon in the direction it will screw on. Hand tighten.

 

[HermanTX]

That type doesn't have an O-ring. Normally theres a threaded female part and a screw on collar with the male side. There's an O-ring located on the female non moveable junction part. It appears you can just clean off the threaded end and reapply the teflon tape. Make sure you clean the female side to the pump too. Apply the teflon in the direction it will screw on. Hand tighten.

See article shown above on threaded PVC pipe.

 

[HermanTX]

Good explanation on PVC threads in another thread.
Post in thread
What did you do to your pool today?

 

[rchadha]

Hi all,
I put more PTFE tape and the threaded joint still leaks a little. Two things are possible-
I either over tightened the joint. I used my hands (no tools), but it’s entirely possible.
Or
I should put some thread sealant . will this one work?
Thread sealant
Thanks all.

 

[PoolStored]

I should put some thread sealant . will this one work?
Thread sealant

This one is better. T plus 2 is a lubricant. Rectorseal 5 is PVC compatible and is not a lubricant.

Amazon.com

 

[rchadha]

This one is better. T plus 2 is a lubricant. Rectorseal 5 is PVC compatible and is not a lubricant.

Amazon.com

Thank you. So I am reading the forum and some suggest to use PTFE tape and the thread sealant? But it doesn’t make sense as one is a lubricant and one is a sealant?
Should I just use the thread sealant?

 

[PoolStored]

Thank you. So I am reading the forum and some suggest to use PTFE tape and the thread sealant? But it doesn’t make sense as one is a lubricant and one is a sealant?
Should I just use the thread sealant?

This has long been a debate within the forum. Guidance from the manufacturers can vary. The general guidance from the folks here that have been around for the longest, have the recommendation to use Teflon Tape and thread sealant.

There is a good section here on threaded connections:

PVC Repair - Further Reading

www.troublefreepool.com