I have a Cub Cadet self propelled 21" push mower that is a bear to start. I just changed the spark plug, cleaned out the air filter and it has fresh gas and plenty of the correct kind of oil.
My husband and my 17 year old son can start it after 3 or 4 attempts, but I do not have enough strength to pull sharply on the rope. I have noticed that there is 8 or 9 inches or play in the rope before it engages. Is this too much slack and does not allow the flywheel to turn adequately? It seems like it catches but then it doesn't start. Small puff of grey smoke when my husband finally starts it for me. I have heard you can take off the cover and recoil the rope to remove the slack, but the spring unwinds and it usually takes 2 people to get it back together. Worth a try?
Thanks
Jeanette

8" of play is not causing the hard start so I would not bother messing with that spring. How long since its been turnedand has anyone ever adjusted the mixture? If all else fails you could let Sears or a pro tune it up and clean the carb.