Sealing leaking metal pipe threads to PVC joint?

[trader4]

I have a 1" barb male thread fitting that is screwed in to a PVC tee. It was new work and I used teflon tape. Upon water testing, it was barely leaking, maybe a cup a day. Tried tightening it more, didn't make a difference. Took it apart, re-wrapped it with teflon tape really well and now it leaks much worse, maybe quart+ a day.

This is on an irrigation well, so I wish I had never even noticed it as the tiny initial leak wouldn't have amounted to anything. But now that I'm down this path, what next. It would be very difficult to change the T. Since it's an irrigation application, I'm thinking of using Permatex as a next step. Only concern would be if Permatex could destroy the PVC over time? Any other ideas? TIA

[The Daring Dufas]

I've had good luck with a product called Leak Lock.

It's at all the supply houses around here and should be available nationwide.

TDD

[Lp1331 1p1331]

TDD is right on the money with LeakLock. We have been using it for about

40 years. Blue Goop we call it. The main supply house that we use quit carrying it, and have a blue pipe dope they claim is nearly the same thing (it's not), and also say that they quit making the original. I found it at a different supply house and now just buy it there out of my pocket-- it's worth it. Only one word of caution-- be careful and don't get it on your hands, and especially don't touch anything of value when you do- VERY difficult to remove. Larry

[Harry K]

One should never make a metal to pvc join with a male metal fitting. A bit of overtightening will crack the pvc fitting. I learned that the hard way when I had to dig up one buried 4 ft deep to fix the leak. I buried it in about August and the leak appeared in January running out from under the snow.

Anyhow. I have had no problem with either joint compound or teflon tape. Have had one or two very slow leaks that sealed themselves after a time.

Harry K

[gfretwell]

I bet you cracked the tee. As a general rule, never thread metal into PVC. If you have to use a PVC female part, like this tee, put a short plastic nipple on it and use a female metal connector.

[Tony Hwang]

Hmmm, I use snug fit hose clamp to lessen that risk. Too much tightening is often cause of trouble.

[Lp1331 1p1331]

Actually, the OP never said the male fitting was metal-- only a male barb type fitting, which could also mean they gray one for poly pipe. However, it probably still would have been preferable to have the PVC connector male and whatever screwed onto it a female. Ideally a regular PVC tee with a short piece of pipe and then a F/A glued onto that, but it is a little late for that now. Larry

[gfretwell]

I guess I was tricked by the title of the thread ... sorry

[Lp1331 1p1331]

Duhh --sorry I was reading the post and totally ignored the title. Not the first dumb thing I have ever done and surely won't be the last. Larry

[Stormin Mormon]

I've had good results with Rectorseal #5. Of course, Permatex #2 non hardening would work, instead. Dissemble, and put on fresh teflon. Put the sealant on top of the teflon, and then thread the fitting on. Do not put sealant into the fitting. Just on the exposed threads.

[Jules]

I went one better and read the original post, typed a reply, realised suddenly that I couldn't see any mention of metal in the original post, and canned my reply before sending. D'oh. Now all the useful stuff's been said, I think :-)

[The Daring Dufas]

Hey, I use that Rectumseal #5 too. 8-)

TDD

[DD_BobK]

as per the other posts....I quit doing "male metal pipe threads into female PVC fittings".

I only cracked one but that was enough. Now its male PVC into metal.

But to the problem at hand.......you could try the one of the various "goops" being suggested

compatible with PVC

or since (imo) the fitting is probably cracked.... to fix the real problem.

Screw the metal bard fitting into a metal coupling, screw a PVC short nipple into the coupling. Prime, glue & screw the PVC/metal assembly into PVC tee. Allow several hours to cure & you should be good to go.

cheers Bob

[JIMMIE]

The only problem I have with the tape is that people tend to use too much of it.

Jimmie

[trader4]

Thanks for all the tips. I ordered a tube of Leak Lock on Ebay. Will let you all know how it works out, assuming it gets here before the sprinkler guys blow out the system. The reason I used the metal barb was that the inside diameter of the metal barbs is a little larger and since this is at the head end of the system, wanted to get max flow. I've also found that they are easier to work with. I don't think I cracked the T as I was careful not to overtighten it. Also, it was leaking from the start when it wasn't real tight to begin with and I would suspect if it actually cracked it would be leaking worse.