[cooperino]

Originally Posted by C&O2-10-4

Recently my CCC 3240 would backfire when I shut it down, ( I do throttle down before I turn it off); anyway I was mowing the other day for several hours and all of a sudden it just quit, I believe I heard a pop when that happened. I can't get it started, could I have a bent engine valve ? cannot see anything wrong, no oil, or crack in the engine block.

C&O2-10-4

Now to actually help the OP....

You should of course make sure you have fuel and its getting to carb. Check spark both cylinders. If both are present I would pull one plug at a time and see if you have compression. If you don't have a compression gauge you should still be able to feel the pressure coming out off park plug hole.

If this was as an abrupt stop as you say it was and you heard a pop other than the backfire sound there may be a bent/broken valve or a blown gasket.