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.
Small engine primer bulb. The primer bulb draws additional fuel into the carburetor to help start the engine.
Duck bill valve
Guide bar nut hex 5/16-18
Oil pump assembly