Stihl MS 250C Instruction Manual page 10

English
Installing the Toolless Fuel Cap
WARNING
1
2
An improperly tightened fuel filler cap
can loosen or come off and spill
quantities of fuel. To reduce the risk of
fuel spillage and fire from an improperly
installed fuel cap, correctly position and
tighten the cap in the fuel tank opening:
Raise the grip on the top of the cap
–
until it is upright at a 90° angle.
Insert the cap in the fuel tank
opening with the exterior positioning
mark (1) lined up with the
"unlocked" symbol (2) on the fuel
tank housing.
Using the grip, press the cap down
–
firmly while turning it clockwise to
the closed position (approximately
1/4 urn). In the closed position, the
interior (4) and exterior (1)
positioning marks will align with the
"locked" symbol (3) on the fuel tank
housing.
Fold the grip flush with the top of the
–
cap and check for tightness.
8
Misaligned, Damaged or Broken Cap
WARNING
A
4
1
2
3
If the cap does not drop fully into the fuel
tank opening when the positioning
marks (1, 2) line up, or if it does not
tighten properly when turned, the base
of the cap may be prematurely rotated in
relation to the top. Such misalignment
can result from handling, cleaning or an
improper attempt at tightening.
Illustrations A and B: The base of
–
the cap is prematurely rotated to the
closed position and is not in the
correct starting position for
installation. The tank will not seal in
this configuration. Note: in
Illustrations A and B, the interior
positioning marks (1) are in line with
the exterior position marks (2).
Illustration C: The bottom of the cap
–
is in the correct starting position for
installation. Note: In Illustration C,
the interior positioning mark (1) is
under the grip and not in line with
the outer position mark (2).
To return the base of the cap to the
proper starting position for installation:
B C
1
1 1
2 2
B
A
Drop the cap into the fuel tank
N
opening (A).
Next, turn the cap counter-
N
clockwise with slight pressure until it
drops fully into the fuel tank opening
(approximately 1/4 turn) (B). This
will rotate the base of the cap into
the correct starting position for
installation (C). The exterior
positioning mark (1) on the cap will
line up with the "unlocked"
symbol (2) on the fuel tank housing.
The interior positioning mark should
be under the grip and not in line with
the outer positioning mark (1).
Then, turn the cap clockwise,
N
closing it normally.
If your fuel cap still does not tighten
properly, it may be damaged or broken.
Stop using the chain saw and take it to
your authorized STIHL dealer for repair.
Vapor Lock
WARNING
Vapor lock occurs when fuel in the fuel
line or carburetor vaporizes, causing
bubbles to block the free flow of liquid
fuel into the carburetor. Vapor lock
cannot be relieved or affected by
opening the fuel tank. Removing the fuel
filler cap without first allowing the chain
saw to cool adequately can result in fuel
C
1
2
MS 250