Stihl KM 94 R Instruction Manual - Page 19

English Engine Management Adjusting the Carburetor Spark Plug Exhaust emissions are controlled by the design of the fundamental engine parameters and components (e.g. carburation, ignition, timing and valve or port timing) without the addition of any major hardware. The carburetor has been set at the factory to provide an optimum fuel-air mixture under most operating conditions. Adjusting idle speed Engine stops while idling N Turn the idle speed screw (LA) slowly clockwise until the engine runs smoothly - the attachment must not run. Attachment runs when engine is idling N Turn the idle speed screw (LA) slowly counterclockwise until the attachment stops running. WARNING If the attachment continues to run when the engine is idling, have your machine checked and repaired by your servicing dealer. 0208BA036 KN 0208BA037 KN If engine is down on power, difficult to start or runs poorly at idling speed, first check the spark plug. Fit a new spark plug after approx. 100 operating hours or earlier if the electrodes are badly eroded. Wrong fuel mix (too much engine oil in the gasoline), a dirty air filter and unfavorable running conditions (mostly at part throttle etc.) affect the condition of the spark plug. These factors cause deposits to form on the insulator nose which may result in trouble in operation. Removing the spark plug 2 1 N Turn screw (1) in cap (2) until cap can be removed N Lay down cap KM 94 R 17