Is it possible to repair pipe threads...NPT?

I have a 1/8 27 NPT hole that accepts an oil gauge fitting...its aluminum, it will tighten up, but leaks...I tried to tighten more and it started to feel loose. So the question is...can I fix it...tap or heli-coil. Any help would be greatly appreciated!

 

The threads are probably junk. I'd drill it out and run a 1/4 pipe tap in it for new threads then use a 1/4 to 1/8 pipe reducer to get back to 1/8 pipe.
I hope this helps,

 

The easiest way would be to drill it out and tap the hole with a 1/4" npt. Then use a 1/4 x 1/8 npt bushing. Pipe threads are tapered. I've never seen a heli-coil for pipe threads.

 

I concurr.. No such thing as a helicoil for NPT since it is a sealing thread. Since it's an oil fitting you DO NOT want to rig it with epoxy... Drill and retap one size up.

 

I had the same problem in br*** once. Most better auto parts stores will carry NPT tap sets. Be careful to not get shavings in the oil, or it could become a much more expensive problem!

 

Have you tried Teflon Tape on the threads? Sometimes if a bare pipe joint leaks, a few wraps of teflon tape will seal the threads. You can get a roll of it at the hardware store for about a dollar.

 

as brought up before i would punch it out a bit and run a touch bigger tap in it and then reduce it down. i think this is your best bet
Permatex makes a tread repair kit it works well on fixing stripped out holes just be carefull it can make a mess quit and really look like hell if done carelessly, and its not a big fan of vibration. Only use this in case it cant be punched out its easy to F#@K up

IF you didnt have Teflon Tape or pipe dope on all pipe threads that are holding a fluid or air that just lack of common sence.

 

Tape won't fix stripped or dammaged threads. The treads are the sealing surface.

 

Thanks for the help guys....I think I am screwed though, the stripped threads are actually inside the oil pump and the fitting holds a check ball and spring...so drilling is out of the question and I dont think I want to put any thing on the threads that I why I was hoping I could repair it some how....anyone have an oil pump for a 72 sportster!?!

 

I know you probably don't want to hear this but you may want to TIG it full and retap it.