Stihl BG 55 Product Instruction Manual - Page 21

43 English Engine Management Adjusting the Carburetor 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. Carburetor with Idle Speed Screw (LD) The carburetor comes from the factory with a standard setting. This setting provides an optimum fuel-air mixture under most operating conditions. Standard Setting 295BA046 KN 295BA022 KN N Take the filter (3) out of the filter housing (4). N Install a new filter. As a temporary measure you can knock it out on the palm of your hand or blow it out with compressed air - do not wash. Replace any damaged parts. N Fit the filter (3) in the filter housing (4). N Fit the filter cover (2) so that it snaps into position. BG 55, BG 65, BG 85, SH 55, SH 85 - LD + N Check the air filter and clean or replace as necessary. N Warm up the engine. N Carefully screw the idle speed screw (LD) counterclockwise (lefthand thread) down onto its seat. Then open it two full turns clockwise (standard setting). 19