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

► Remove the fuel tank cap.
NOTICE
■ Bright light, sunlight and extreme tempera‐
tures can cause the fuel mix to separate much
faster. The saw can be damaged if it is used
with a fuel mix that has become separated.
►
Thoroughly mix the fuel.
► Do not use fuel mix that has been stored for
more than 30 days.
► Fill the tank to within no more than 15 mm
of the brim, taking care not to spill any fuel.
► If the grip on the fuel tank cap has dropped
into the closed position: Raise the grip until it
is vertical.
2
3
1
0000-GXX-2935-A1
1
4
► Place the cap in the filler opening so that mark
(1) lines up with mark (2).
► Press the cap down and rotate it clockwise as
far as stop.
The cap snaps into place. The mark (1) is in
line with mark (4) and points to mark (3).
► Check to see if the fuel tank cap can be pulled
upwards and off.
► If the fuel tank cap cannot be pulled upwards
and off: Fold the grip flush with the top of the
cap.
The fuel tank is closed.
If the fuel tank cap can be pulled upwards and
off, perform the following steps:
► Place the fuel tank cap in the filler opening – in
any position.
0000-GXX-3136-A1
1
2
ABC
► Press the cap down and rotate it clockwise as
far as stop.
► Press the cap down and rotate it counterclock‐
wise until mark (1) points to mark (2).
► Now try again to close the fuel tank.
► If the fuel tank still cannot be closed properly:
Do not use the chainsaw and contact a STIHL
dealer for assistance.
The chainsaw is not in a safe condition.
9 Starting and Stopping the
Engine
9.1 Starting the Engine
1
2
3
0000-GXX-A391-A0
► Engage the chain brake (2).
► Pull off the chain guard (scabbard).
► Depress the decompression valve (1).
► Move the Master Control lever (3) to posi‐
tion
.
0000-GXX-2936-A0
► Hold the chainsaw firmly in one of three ways:
–
Place the saw on level ground. Hold the
saw firmly on the ground with your left hand
on the handlebar – your thumb should be
under the handle. Put the toe of your right
boot into the rear handle and press down.
–
Place the saw on level ground. Hold the
saw firmly on the ground with your left hand
on the handlebar – your thumb should be
under the handle. Put the heel of your right
boot into the rear handle and press down.
–
Hold the saw firmly with your left hand on
the handlebar – your thumb should be under
the handle. Hold the rear handle tightly
between your legs, just above the knees.
English 9 Starting and Stopping the Engine
14 0458-759-0121-D. VA0.A21.