Hello,

Back in December I received help in replacing my main shut off valve. Here's the thread: https://www.askmehelpdesk.com/plumbing/how-attach-3-4-shut-off-valve-cast-iron-293990.html#post1438939

The problem I'm having is my fittings aren't water tight. I'm assuming the problem is the cheapo pipe tape I used from HD (the tape is white, but the packaging was blue, if that helps).

So, my question is: Should I use teflon tape, and if so, what kind? Or, should I use pipe dope, and if so, what kind? And, last, should I use a combination of the two?

Thanks in advance.

Seth

Use Teflon tape. It should say PTFE somewhere. Use 2-3 wraps in the direction of tightening. The addition of PST (pipe sealant) is an excellent precaution since you have to undo the connection anyway. Loctite 567 is a quality sealant but there are many other brands available. Tighten the connections to "3 threads showing".

Pipe threads take a wile getting used too. You need o go about 2.5 turns past finger tight. The connecions are tight to turn. It's a common mistake. You alsost fell your tightening too tight, but your not.

Thank you for the help!

Tape should be used when dealing with plastic fitting mainly plastic male thread water fitting, reason being if you use pipe dope on plastic male threaded fitting for water supply, the dope tends to make the threads too slick causing over tighten of the fitting.

I prefer pipe dope on galvanized or stainless pipes that I need a monkey wrench on. I use Teflon tape on plastic fittings, and flex tubing, like under sinks, good luck.

John

As always, the advice here was dead on. I used a combination of teflon tape and rector seal #5 and the fitting is dry. Thanks again.

Am glad that we could help, Thanks.

John

Thanks for the update Bergs. We appreciate hearing if our solutions work. Good luck, Tom