Owner's Manual

MS 251, MS 251 C
English
7
position for installation. Then, twist
the cap clockwise, closing it
normally.
N If your cap still does not tighten
properly, it may be damaged or
broken; immediately stop use of the
unit and take it to your authorized
STIHL dealer for repair.
See also the "Fueling" chapter in your
Instruction Manual for additional
information.
Before Starting
Take off the chain guard (scabbard) and
inspect the saw for proper condition and
operation. (See the maintenance chart
near the end of the instruction manual.)
WARNING
Always check your power tool for proper
condition and operation before starting,
particularly the throttle trigger, throttle
trigger lockout, stop switch and cutting
tool. The throttle trigger must move
freely and always spring back to the idle
position. Never attempt to modify the
controls or safety devices.
WARNING
Never operate your power tool if it is
damaged, improperly adjusted or
maintained, or not completely or
securely assembled.
WARNING
Check that the spark plug boot is
securely mounted on the spark plug – a
loose boot may cause arcing that could
ignite combustible fumes and cause a
fire.
For proper assembly of the bar and
chain follow the procedure described in
the chapter "Mounting the Bar and
Chain" of your instruction manual.
STIHL Oilomatic chain, guide bar and
sprocket must match each other in
gauge and pitch. Before replacing any
bar and chain, see the chapter entitled
"Specifications" in the instruction
manual and the section "Kickback" and
the "ANSI B 175.1-2000 chain saw
chain saw kickback standard" below.
WARNING
Proper tension of the chain is extremely
important. In order to avoid improper
setting, the tensioning procedure must
be followed as described in your
manual. Always make sure the
hexagonal nut(s) for the sprocket cover
is (are) tightened securely after
tensioning the chain in order to secure
the bar. Never start the saw with the
sprocket cover loose. Check chain
tension once more after having
tightened the nut(s) and thereafter at
regular intervals (whenever the saw is
shut off). If the chain becomes loose
while cutting, shut off the engine and
then tighten. Never try to adjust the
chain while the engine is running!
Keep the handles clean and dry at all
times; it is particularly important to keep
them free of moisture, pitch, oil, fuel mix,
grease or resin in order for you to
maintain a firm grip and properly control
your power tool.
Starting
WARNING
To reduce the risk of fire and burn
injuries, start the engine at least 10 feet
(3 m) from the fueling spot, outdoors
only.
Start and operate your saw without
assistance. For specific starting
instructions, see the appropriate section
of the instruction manual. Proper starting
methods reduce the risk of injury.
WARNING
To reduce the risk of injury from chain
contact and / or reactive forces, the
chain brake must be engaged when
starting the saw.
WARNING
Do not drop start. This method is very
dangerous because you may lose
control of the saw.
There are two recommended methods
for starting your chain saw.
With the first recommended method, the
chain saw is started on the ground.
Make sure the chain brake is engaged
(see "Chain Brake" chapter in your
instruction manual) and place the chain
001BA113 KN