well i got the expansion valve off, but now it wont thread back in. super frustrating.also the one i removed had r134a stamped on it and i use r-12. do you think thats why it started leaking?

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1984 300SD Orient Red/ Palomino
1989 560SEC
2016 Mazda 6 6 speed manual
1995 Ford F-150 reg cab 4.9 5speed manual