Yeah but letting it sit can make things worse if there's moisture trapped in there. It just gives more time for corrosion to set in. I've had better luck with careful heat and a long lever, not just waiting. Brooke_knight is right about ammonia being a bad idea for carbon, but even on steel or aluminum, that stuff can creep into frame joints and cause hidden problems later. Sometimes you just need steady force and the right tools, not more chemicals or waiting around.

Try turning your oven light on.

Yeah, the "max RPM for everything" phase... I think we all live there for a while. I was the same way, just hammer down until the day I tried that in some thick clay and shook a fitting loose that took me three hours to find in the bilge. Felt real smart that day. Dialing it back for the soft stuff just makes sense.