Got a can of Restore (based on forum recommendations) but in trying to remove the oil filler cap, I CAN'T GET THE THING TO TURN LEFT. I can tighten and it turns and clicks, like a cap with the safety release to prevent over-tightening. When I try to turn it to the left, I can't budge it. I am a little afraid of breaking it, but am using quite a bit of force. Any suggestions?

It's off. Let it cool a little more. Decided that whether it broke or not, I needed to get the thing open eventually. Seemed to give with actually less force than I'd applied before, but frustration may have added a bit. Hmmm...

Don't know whether it was more force, cooler head, hotter head, or cooler engine, but it's open and Restore is installed.

For some reason, walking away and then giving it one more try seems to work more often than not.........