I think the motor internally is fine, as when I shut it off it was idling smoothly, but I'm not sure about the headgasket. I drained the oil and it's appearance disturbed me. Here's a pic of the drain plug. Look at how the left side is completely bent, also the washer that was on it is like melted to it and coming off in chunks (on the top left you can see a piece of the washer sticking up):
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