Leo, it sounds like your engine needs a good overall service.
Im sure you would like it to start reliably and run well for this growing season and more to come.
If that engine came to me, I would flush out the fuel tank, clean the carby, clean the air filter, clean the spark plug or replace it, clean the magnet faces & magneto armature faces and reset them, clean all excess carbon from the head.
Plus check the things Grumpy has said & more.......
Joe earlier on offered to service it for you.
If you want to service it yourself step by step we can do that to.
