many years ago, I was doing a build with engine in frame, but no spark plug in it so I could feed chain thru - continuing the build, I was putting gas tank on and dropped one of the nuts
I immediately realized that I could not start the motor until that nut was found, and looked for quite a while for it with no luck dragging a magnet all around the area & looking under stuff with a flashlight
opened the head and saw piston was down leaving exhaust port open and realized that the tinny sound I heard after the drop, was probably the nut bouncing off the piston into the muffler - took off muffler and turned it upside down and nut fell out and all was good
since then, I always keep a rag over the head while feeding chain and replace plug as soon as chain is on
Yesterday, a poor kid came back with new motor locked up after 20 seconds of run - once I hammered the piston out, the broken pieces looked a bit like one of the lock washers from the gas tank fell in, but it was hard to tell - sold him a brand new motor for $50, since I can sell mag & clutch & side covers and some of the other parts as still new out of the one that was destroyed, but I'll lose hours of labor getting it all out.
short version is:
DO NOT WORK ON THESE WITH THE SPARK PLUG HOLE OPEN
I immediately realized that I could not start the motor until that nut was found, and looked for quite a while for it with no luck dragging a magnet all around the area & looking under stuff with a flashlight
opened the head and saw piston was down leaving exhaust port open and realized that the tinny sound I heard after the drop, was probably the nut bouncing off the piston into the muffler - took off muffler and turned it upside down and nut fell out and all was good
since then, I always keep a rag over the head while feeding chain and replace plug as soon as chain is on
Yesterday, a poor kid came back with new motor locked up after 20 seconds of run - once I hammered the piston out, the broken pieces looked a bit like one of the lock washers from the gas tank fell in, but it was hard to tell - sold him a brand new motor for $50, since I can sell mag & clutch & side covers and some of the other parts as still new out of the one that was destroyed, but I'll lose hours of labor getting it all out.
short version is:
DO NOT WORK ON THESE WITH THE SPARK PLUG HOLE OPEN
