Small Engines need just as much care as an automobile. The number one procedure to help extend the life or your lawn mower is to change the oil at the proper times. You should change the sparke plug and get the blade sharpened each year. Clean the air filter or change the air filter every year. A two cycle engine needs special care. the fuel lines and tank fuel filter need to be changed every two years. The fuel lines get brittle and break at the two year period.
One of the problems that a two cycle engine has when it comes to weed eaters and chainsaws is the exaust system clogs over time. This happens when too much oil is mixed with the fuel. Carbon builds up in the exaust port and plugs the ports. Keep oil fuel mixture at the right ratio.