Hi,
Because of the seasonal nature of the use of these types of equipment, suspect a dirty carb and bad fuel.
Peace,
Clarke

First of all check or replace spark plug,then check fuel supply and fuel filter.Consider replacing both.
Also make sure you add no more than 2.6 ounces of oil(Preferably Synthetic) to 87 Octane fuel.
When you have started it finally,its time to remove carbon,and change or replace air filter.
There is a product called "Power Foam",an Amsoil Product that will clean the carburator,combustion chamber,
And exhaust system.When finished the engine will pick up 200-300 rpms on the top end and start like new again.
Any further questions please call:360-281-7283
Sam The Amsoil Man

Don't know why he would want to add oil to his fuel .

He suggested it was a"2-Cycle engine !