I have an anti-syphon outdoor water faucet that leaks near the handle so we turn the water off inside the house. The handle will turn all the way on and off but I cannot get the handle screw off to replace washers. I have applied Liquid Wrench penetrating oil. Do I just repeat the application until the screw turns? Is there something else I can do?

My outside faucet handle turns but will not turn off at all. The handle just turns. We keep it on and turned off the inside valve. Since I know the handle has to stop in the open position to turn the screw to get it off, and it does not stop, I cannot get the screw to turn to take the handle off. Can this one be repaired? Do I cut the anti-freeze handle off to get to the nut under it to turn that?