Check the oil level very carefully.
If the carb is flooding the fuel will flow into the cylinder & ultimately into the sump .
This both dilutes the oil and raises the oil level.
Running with too high an oil level will cause the engine to smoke badly.
Running with too thin oil will also cause the engine to smoke badly.
IT will also make the engine hard to start.
IT would be immensely helpful if you told us the actual engine numbers so we know exactly what you are dealing with.
Also "Difficulty Starting" is a useless term to help us to diagnose your problems.
Like walking into the doctors and saying "I feel sick"
The doctor can then take some readings ( pulse, temp etc ) but we are left with nothing but what you tell us.
Starting with a thorough tune up would be a good idea
The engine manual can be found here, it is a free download
http://www.mymowerparts.com/pdf/