Small engine primer bulb. The primer bulb draws additional fuel into the carburetor to help start the engine.
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.
NGK Spark Plug (BPM8Y). 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.
Echo fuel pipe/vent tube
Fuel tank vent (also called a check valve). The fuel tank vent allows air to re-enter the fuel tank. If the vent is clogged, the engine may stall.
NGK Spark Plug (BPMR8Y)
Spark plug wire terminal
Spark plug boot
Chain tension adjustment gear
Flange nut 6
Chain tension adjustment gear screw