Anti siphon valve……

[charlie_the_tuna]

So I’ve been hitting it with liquid wrench every other day for about a week now. Lightly tapping it with a hammer hoping to shock the threads into sucking some of that penetrant in. Took a wrench to it yesterday and it’s on there pretty good. I have to imagine it’s the original 30 year old hardware.
I don’t want to gorilla this thing off because I figure if I damage the fitting on the tank (plastic), I’m done for.
I’m gonna go down today and repeat the process of spray, tap and twist. If it doesn’t give, I’ll do it again tomorrow and every day until something gives.
Unless anybody has a better idea…. I’m all ears.