Small Engines (Lawn Mowers, etc.): Craftman mower made a loud clank noise and stop working, craftman, oil cap

Question
I have a old Craftsman mower I think it's like a 1985.  When I was mowing it made a loud clank noise and stop working. It sounded like I hit a metal pipe. Now the mower will not start.  Does this sound like I through a rod, and is this something that can be fix or is this a new engine.  It had oil but when I took off the oil cap it was smoking pretty good.

Answer
It certainly doesn't sound very good.  If you did break a rod, you may be able to rebuild the engine.  It just depends on what, if any, damage was done inside the block.  If you can't turn the engine over by hand, or if you can and there's a rattling noise from inside or the piston doesn't move, then the engine will need to come apart.  I'd say we rebuild about half the mid to large engines that toss rods.  Thanks, PK.