I was taking my O2 sensor out of my 96 outback and the bung that holds the O2 sensor in came out,has anyone ever had this happen to them and can a new bung be welded in to the catalitic converter or do i have get a whole new catalitic converter?

Hi Steve, Yes you can buy the bung, any good parts

house that handles exhaust parts will have them.

 

A good MIG welder can weld it back on, but you will not doubt have to remove said cat.

I took the exhaust from the back cat to the heads off.I didnt know if the bung could be welded on,looks like the old one was soldered on.

I'd imagine an exhaust shop could weld a bung on pretty fast (and hopefully even cheap since you already have the exhaust removed!).

 

You could maybe TIG weld it back in but I don't know since I just started reading welding for dummies.

Any muffler shop or weldor should be able to do that for you.

 

If it were me, I'd try to silver braze the bung on. It's easier to get a good seal with brazing, since the filler flows like solder. Silver brazing is compatible with stainless steal, which is what the cat is made of. I can weld (MIG and gas), but my skills aren't enough that I would be sure of a good seal.

 

Don't try to use solder, like for plumbing or electronics. It won't stick to stainless steel (at least not easily), and it melts at too low of a temperature.