It sounds like this mower was run low on oil and the engine locked up due to lack of lubrication. This may run again with some simple steps but the life of the engine has been greatly reduced. The mower may smoke more and not have as much power if you can get it going again. The quick and dirty way to get this going is as follows...
1. Fill oil level up to normal.
2. Remove the spark plug wire
3. Turn the mower up so that you can access the blade
4. Try turning the blade by hand. If this doesn't work, try placing a board against the trailing side (not cutting side) of the blade banging on it with a hammer. The wood will protect the rest of the blade/engine from the shock of the hammer.
5. If it feels like it frees up, try to start the mower like normal except that the spark plug is still out.
6. If it turns freely, put the plug back in and try to start like normal.
7. If it starts, let it run like a minute and then change the oil.
8. Run with new oil for one mowing and change the oil again.
9. If this works, you are lucky but I have seen it work before. This has greatly reduced the life of the motor and it will likely not handle another such episode. I have seen several blow up after a while! Be careful and be sure to check the oil level frequently (every mowing if there is a lot of blue smoke -oil is burning!). Also be sure to change the oil at least once every season.
Conor
July 2009
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