If an engine fails to start, the failure can be associated with several issues. These include oil that has deteriorated, a fuel that has overstayed, a dirty spark plug or air filter, among others. The engine comes with a manual that guides on how to troubleshoot to restore its functions. These include replacing the fuel if it is stale, filling the fuel tank in case the tank is empty, replacing the plug, the kill switch, or the air filter, among others.