Along with a shot of penetrant before hand, and a good line wrench, always remember to TIGHTEN the fitting a little first, instead of just trying to loosen it. Tightening fasteners/fitting a wee bit before taking them off always seems to break them loose easier.
Another trick I've learned over the years when I have a stubborn fitting is to put my line wrench on the fitting, and smack the tip of the wrench with a hammer a few times. NOT from the side, like you were trying to loosen it, but from the very END. This seems to work best for me. Of course, there's always that ONE that just ain't givin up without a fight, and you wind up with a torch...threatening to burn the whole dang place down.....
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Joel Adams
C3VR Lifetime Member #56
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"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"