Stihl MS 391

2 MS 311, MS 391
Contents
12. Fuel System 68
12.1 Air Filter 68
12.2 Baffle 68
12.3 Filter Base 68
12.4 Air Guide Shroud 69
12.5 Carburetor 71
12.5.1 Leakage Test 71
12.6 Servicing the
Carburetor 72
12.6.1 Metering Diaphragm 72
12.6.2 Inlet Needle 73
12.6.3 Pump Diaphragm 74
12.6.4 Air Valve 76
12.6.5 Levers on
Throttle Shaft 76
12.6.6 Adjusting Screws 77
12.7 Carburetor
Adjustment 79
12.7.1 Basic Setting 79
12.7.2 Standard Setting 80
12.8 Carburetor Carrier 81
12.9 Intake Manifold 82
12.10 Tank Vent 83
12.10.1 Testing 83
12.10.2 Removing and
Installing 84
12.11 Fuel Intake 84
12.11.1 Pickup Body 84
12.11.2 Fuel Hose 85
12.11.3 Fuel Suction Hose 86
12.11.4 Tank Housing 87
13. Special Servicing
Tools 88
14. Servicing Aids 90