Problem with cast iron baseboard valve

Alfaguy22

Hey guys. Ive got a bit of an issue. I had a leaky valve that I could not get off. Long story short, I eventually broke it and had to drill out the threads. I got most of it After wards I used a tool a guy a Lowes recommended to get the remaining threads out. I believe I got it all out, but now the issue is the new valve seems a little too small. I cant get it to tighten. My question is, can I use either JB weld it RTV silicone (high heat?) to secure it in place?

Pumpguy

What is the thread size? You might want to try the thick yellow Teflon tape typically used for gas connections. Some use a belt and suspenders approach with both Teflon tape and pipe dope. I am sure others can be more specific about their favorite dope.

Alfaguy22

its 1/8 sized.

ethicalpaul

Is this a 1/8" NPT air vent port? I guess it doesn't matter but I'm trying to visualize it. A photo would be great.

But in the end, if your new valve is the right size and it just spins, then you may have drilled out the old threads. You might try drilling and tapping for the next size up, 1/4" and then bush it back down to 1/8. You can get NPT taps on Amazon, probably not at the big boxes.

EBEBRATT-Ed

Agree with @ethicalpaul

Drill and tap it 1/4"npt