Thread repair tip

[davepl]

Yesterday I cross-threaded the top fitting on my brand new AC condenser. If the fitting couldn't be saved, the whole unit (250 or so, I imagine) was toast. If I had a magical tap that went together in two halves I might have been able to "back it out" and fix the end threads.

I'm fortunate to have a local shop that only works on old cars (pre computer) and is staffed by guys in their 60s that have forgotten more than I know.

The owner (Jim) told me that there is indeed such a tap, but didn't have one on hand that big (13/16" I think). But what he did have is a thread file, something I've managed to never hear of in 20 years of shadetree work.

So, he gave me his thread file, I figured out it was 16 threads per inch, and he told me to be patient and work slowly. He did have a one-piece die big enough, but it's a crapshoot of where you start it if you're going to wind up on the same threads.

The thread file, however, allowed me to fix the threads well enough that I could turn the tube nut on by hand. Saved the entire condenser for me. Pretty sure that a dealership or other shop would have told me the condenser needed to be replaced.

I hope at places like Wyotech or community colleges they're still teaching that kind of stuff, because there's more to a good tech than reading OBD2 codes and replacing modules!