Stihl MS 661 C-M User Manual

2 MS 661, MS 661 C-M
Contents
10. AV Elements 80
10.1 Stop Buffer at
Clutch Side 80
10.2 Antivibration Element
on Oil tank /
Tank Housing 80
10.3 AV Element on
Fuel Tank 81
10.4 AV Element on
Handlebar 83
10.4.1 Stop Buffer at
Ignition Side 83
10.5 Handlebar 83
10.5.1 Handlebar / Wrap
Around Handlebar with
Heating 85
11. Control Levers 88
11.1 Switch Shaft 88
11.1.1 Removing and
Installing 88
11.2 Throttle Trigger /
Lockout Lever 90
11.3 Throttle Rod 91
11.3.1 Choke Rod
Models without
M-Tronic 93
12. Chain Lubrication 94
12.1 Pickup Body 94
12.2 Oil Suction Hose 94
12.3 Oil Pump 94
12.3.1 Adjusting Uprated
Oil Pumps 96
12.4 Valve 96
13. Fuel System 97
13.1 Air filter 97
13.2 Baffle 97
13.3 Filter Base 97
13.4 Carburetor 98
13.4.1 Leakage Test 101
13.5 Servicing the
Carburetor 101
13.5.1 Disassembling and
Cleaning the
Carburetor 101
13.5.2 Assembling the
Carburetor 102
13.5.3 Metering Diaphragm 102
13.5.4 Inlet Needle 103
13.5.5 Pump Diaphragm 104
13.5.6 Lever on
Throttle Shaft 105
13.5.7 Lever on
Choke Shaft 106
13.5.8 Lever on Choke Shaft /
Switch Unit,
Models with M-Tronic 106
13.6 Adjusting the Carburetor,
Models with M-Tronic 107
13.7 Adjusting the Carburetor,
Models without
M-Tronic 107
13.7.1 Adjusting Screws 107
13.8 Adjusting the
Carburetor 109
13.8.1 Basic Setting 109
13.8.2 Setting 109
13.8.3 Standard Setting 110
13.9 Manifold 111
13.9.1 Impulse Hose 112
13.10 Tank Vent 113
13.10.1 Testing 113
13.10.2 Removing and
Installing 113
13.11 Fuel Intake 114
13.11.1 Pickup Body 114
13.11.2 Fuel Suction Hose in
Tank Housing 114
13.11.3 Fuel Suction Hose on
Carburetor 115
13.11.4 Tank Housing 115
14. Heating System 118
14.1 Carburetor Heating 118
14.1.1 Testing the Complete
System 118
14.1.2 Testing the Heating
Element 118
14.1.3 Thermostatic Switch 119
14.2 Carburetor Heating
System Troubleshooting
Chart 120
14.3 Handle and Carburetor
Heating System 121
14.3.1 Troubleshooting 121
14.4 Heater Switch 122
14.5 Heating Element in
Rear Handle 123
14.6 Heating Element in
Handlebar 124
14.7 Generator 124
14.7.1 Handle Heating and
Generator Trouble-
shooting Chart 126
14.7.2 Test Connections and
Test Values 128
14.8 Heating Element
Connecting Wires 130
14.8.1 Connecting Wire
between Rear Handle
and Handlebar 130
14.8.2 Connecting Wire
between Rear Handle
and Generator 131
15. Special Servicing
Tools 134
16. Servicing Aids 136

Stihl MS 661 C-M Specifications

General

Idle speed	- RPM
Motor type	2-stroke motor
Chain pitch	3/8 \
Blade length	800 mm
Product color	Black, Grey, Orange
Automatic oiling	Yes
Engine displacement	91.1 cm³
Power source	Gasoline
Sound power level	118 dB
Vibration emission	6.9 m/s²
Sound pressure level	105 dB

Weight and Dimensions

Weight	7400 g