As I was looking for info on how to drain oil from my lawnmower (reference this post), I came across a video that discussed hydrolocking, which is something I'd never heard of. I've seen other posts in this forum that suggest symptoms point to hydrolocking, but I've seen no information on how to prevent it. The Youtube video linked below apparently shows how to prevent this by ensuring the piston is at top dead center on the compression stroke so that the valves are closed, thus preventing oil from getting into the piston chamber. Thoughts?