So somehow, one of the spark plugs popped out while I was driving along. The thread snapped from the bolt and is now stuck. Is there a way to get the thread out without damaging the engine? Bare in mind that anything used to loosen it will pour into the spark chamber. I should add that the thread and bolt are highly rusted and the thread is very stuck in place.
Not very technical on this, so the name of any tools or lubricant needed would be very helpful.