Stihl HL 45 0176 Product Instruction Manual - Page 21

Adjusting the Carburetor General Information The carburetor comes from the factory with a standard setting. This setting provides an optimum fuel-air mixture under most operating conditions. Preparations N Stopping the Engine N Inspect cutting blades and clean if necessary (clean, move freely, not warped). N Check the air filter and clean or replace if necessary. N Check the spark arresting screen (not in all models, country-specific) in the muffler and clean or replace if necessary. Standard Setting HL LA N Turn high speed screw (H) counterclockwise as far as stop (no more than 3/4 turn). N Turn the low speed screw (L) carefully clockwise as far as stop, then turn it back 3/4 turn. Adjust idle speed N Carry out the standard setting. N Start and warm up the engine. Engine stops while idling N Turn the idle speed screw (LA) slowly clockwise until the engine runs smoothly - the cutting blades must not move. 233BA050 KN English Cutting blades run when engine is idling N Turn the idle speed screw (LA) counterclockwise until the cutting blades stop moving and then turn the screw about another 1/2 to 1 full turn in the same direction. WARNING If the cutting attachment continues to run when the engine is idling, have your machine checked and repaired by your servicing dealer. Erratic idling behavior, poor acceleration (despite correction to setting of LA screw). Idle setting is too lean N Turn the low speed screw (L) slowly counterclockwise (1/4 turn), no further than stop, until the engine runs and accelerates smoothly. Erratic idling behavior Idle setting is too rich N Turn the low speed screw (L) slowly clockwise (1/4 turn), no further than stop, until the engine runs smoothly and still accelerates satisfactorily. It is usually necessary to change the setting of the idle speed screw (LA) after every correction to the low speed screw (L). Fine Tuning for Operation at High Altitude A slight correction of the setting may be necessary if the engine does not run satisfactorily: HL 45 19