Small engine primer bulb. The primer bulb draws additional fuel into the carburetor to help start the engine.
Champion spark plug (RCJ6Y). The spark plug ignites the fuel and air mixture in the engine's cylinder to power the engine. If the spark plug is has fouled (if the tip of the spark plug is burnt or damaged), the engine may not start or may run rough.
Fuel filter. If the fuel filter is clogged, it will restrict the flow of fuel to the carburetor. As a result, the engine may not start.
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.
Pump filter body
Non-Vent Fuel Cap