A Thread About Threads (O2 Sensor threads)
 

Today I received a Bonez downpipe & cat converter kit from Rotary Performance ("RX7.com"). The O2 sensor fitting on the downpipe has gobs of welding material in the internal threads. I can't pick it out with a sharp tool. Can the threads be chased with a tap? If so, does anyone know the thread size for an O2 sensor? It looks like a 5/8" dia, and I am assuming it's probably a tapered (pipe) thread, but am not really sure. Has anyone had this problem? What's the best fix, ship it back & have it replaced or try & fix it myself?

Thanks!

---- Bill

I say send it back . . .

AFTER rasing hell with them on the phone to pick up the cost of the shipping and a comp fory your trouble.

There is no excuse for shit quality.

Barry

Barry,

I called Ari at RP, and he was not only very apologetic, he told me there is a guy at Bonez who is supposed to follow the welding operation and chase the threads to cure this very problem. He also said RP has a guy who is supposed to run an actual O2 sensor into the fitting to verify it's OK. He was going to "talk to him". More to the point, Ari told me to buy a "spark plug thread chaser" and use the 18 mm end to clean out my fitting. It worked! The 14 mm end can be used to chase the RX-7's spark plug threads if it's ever necessary (hope not). Anyway, problem is cured. Now for the hard part... installation.

BTW, I mentioned that Bonez should move the "Chaser" from behind the welder and put him ahead of the welder with the job of inserting a threaded plug into the fitting before it's welded, thus preventing the problem in the first place. Ari replied, "Yeah, but that would be too easy."

---- Bill