Walbro primer bulb. The primer bulb draws additional fuel into the carburetor to make the engine easier to start. If the primer bulb is leaking, replace it.
Zama carburetor rebuild/repair kit. If the carburetor is clogged, the engine won't get enough fuel. As a result, the engine may not start or may run rough. It is often possible to repair the carburetor if it is clogged.