Instruction Manual
Table Of Contents
- STIHL MS 661 C-M
- 1 Introduction
- 2 Guide to Using this Manual
- 3 Overview
- 4 Safety Precautions
- 5 Preparing the Saw for Operation
- 6 Assembling the Saw
- 7 Engaging and Disengaging the Chain Brake
- 8 Mixing Fuel and Refueling the Chainsaw
- 9 Starting and Stopping the Engine
- 10 Checking the Saw
- 11 Operating the Saw
- 12 After Finishing Work
- 13 Transporting
- 14 Storing
- 15 Cleaning
- 16 Maintenance
- 17 Repairing
- 18 Troubleshooting
- 19 Specifications
- 20 Bar and Chain Combinations
- 21 Spare Parts and Accessories
- 22 Disposal
- 23 EC Declaration of Conformity

NOTICE
■ The engine may overheat if is operated in win‐
ter mode at temperatures above +10 °C.
► Change setting to summer mode.
► Shut off the engine and engage the chain
brake.
1
0000-GXX-A383-A0
2
► Remove the filter cover (1).
► Pull out the shutter (2).
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3
3
► Push the shutter (2) into the guides (3) as far
as it will go.
You will feel it engage.
► Fit the filter cover (1).
11.2 Setting to summer mode
The shutter must be set to summer mode when
working at temperatures above +10 °C.
► Shut off the engine and engage the chain
brake.
0000-GXX-A381-A0
1
2
► Remove the filter cover (1).
► Pull out the shutter (2).
0000-GXX-A384-A0
3
3
► Push the shutter (2) into the guides (3) as far
as it will go.
You will feel it engage.
► Fit the filter cover (1).
11.3 Calibrating the Saw
The chainsaw adjusts itself automatically for opti‐
mum performance during operation. Calibration
enables the saw to be adjusted faster for opti‐
mum performance.
► If the outside temperature is below -10°C or
the engine is cold:
► Start the engine and disengage the chain
brake.
► Warm up the engine by opening and closing
the throttle for about 1 minute.
► Shut off the engine.
1
min
AB C
s> 30 s30-60 s
0000-GXX-3825-A0
►
Move the Master Control lever to position .
► Engage the chain brake.
► Start the engine without depressing the throttle
trigger.
The engine runs and the Master Control lever
remains in position
.
► Run the engine for at least 30 seconds but no
more than 60 seconds (A) without depressing
the throttle trigger.
WARNING
■ If the chain brake is disengaged, the chain
may rotate This can result in serious injuries.
► Hold the chainsaw as described in this
instruction manual.
► Do not touch the rotating saw chain.
► Disengage the chain brake.
11 Operating the Saw English
0458-759-0121-D. VA0.A21. 17