Stihl MS 311 Product Instruction Manual - Page 50

English The following intervals apply to normal operating conditions only. If your daily working time is longer or operating conditions are difficult (very dusty work area, resinrich wood, tropical wood, etc.), shorten the specified intervals accordingly. If you only use the saw occasionally, extend the intervals accordingly. before starting work after finishing work or daily after each refueling stop weekly monthly every 12 months if problem if damaged if required Cooling inlets Clean X Cylinder fins Clean X X Preseparator port and carburetor body Clean "Carb preheat" shutter and preheating port Clean (winter operation only) Carburetor Check idle adjustment - chain must not rotate X X Readjust idle Spark Plug Readjust electrode gap Replace after every 100 operating hours All accessible screws and nuts (not adjusting screws) 3) Retighten Sparl arresting screen4) in muffler Check Clean or replace Combustion chamber Decoke after first 139 hours of operating, then every 150 hours Check X Chain catcher Replace Safety labels Replace 1) STIHL recommends a STIHL servicing dealer. 2) see chapter on "Chain Brake" 3) Firmly tighten down the cylinder base screws of professional saws (3.4 kW or more) after 10 to 20 hours of operation. 4) not in all versions, market-specific X X X X X X X X X X 48 MS 311, MS 391