Stuck relief valve

[MalMac 1,331]

My nephew just pick up a C-160, he can't turn the relief valve to be able to push it. He thinks this valve had not been turned in several years. Anybody got any Ideas how to break it loose without damaging it? I have had some that were stubborn but not like this one.

[300zx 7]

If misery likes company, I will join you. I can't turn the relief on my C161 either.

[ducky 1]

try hitting it with some PB blaster or some other oil and let it soak in and try it. or heat.

[Buzz 502]

Count me in. My free C160 has the valve with the screwdriver slot of which one of the ears is broken. I've sprayed enough PB Blaster on it to float a battleship, or at least a small kayak, and still can'r turn it Wouldn't heat damage some seals or something? Getting ready to start working on it and trying to get it moved into the garage isn't going to be any fun. Any suggestions?

[Kelly 1,029]

I had one I was at wits end trying to turn it, it had the screwdriver slot and I was bending the ears out and was sure they where going to break so I found a nut 5/16 I think, and drilled the center so it fit tight on the valve screw that way when trying to turn the screw the sides did not bend away, then I used a impact driver on it, you know the thing with the changeable bits and you hit the end with a hammer while turning, after about 10 hard wacks it came loose, I didn't want to hit it, but as I said I was fed up with it not rolling around the yard, it was a parts tractor, I had nothing to lose.

[tophatbufflo 2]

A battery charger and a carbon arc welding rod. Ground and hold rod on valve screw It will heat screw up to remove. No flame just heat. Good luck