RE: Crankshaft bolt
Couple of other tricks. With the #1 spark plug removed, engine just before TDC, insert as much 1/4" rope as you can stuff in the top of the cylinder. Make sure you leave enough of a tail so you can get the rope out. Now turn the engine through TDC, the rope should stop engine movement because the rope cannot be compressed. Many small engine shops use this techinque. Another one is to position the breaker bar against something unmovable like the frame rail. Then with the ignition disabled bump the starter to loosen the bolt. Alot of sudden torque, if you are holding the breaker bar watch your fingers!