Stihl MS 440 Service Manual

73MS 440, MS 440 C
The limiter caps have to be
removed from the adjusting screws
only if it is necessary to replace the
high speed screw (H) or low speed
screw (L), clean the carburetor or
carry out the basic setting.
Perform the two following
operations:
: Turn the limiter cap of high speed
screw (H) counter-clockwise as
far as stop until the limiter cap
lugs are in line with the carburetor
openings.
: Turn the limiter cap of low speed
screw (L) clockwise as far as
stop. Turn the limiter cap back
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176RA326
one quarter turn until its lugs are
in line with the carburetor
openings.
Note:
: The lugs of the limiter caps are at
a right angle to the screwdriver
slot.
: Insert puller 5910 890 4500 into
the middle of the limiter caps and
press down lightly, turning
counterclockwise at the same
time, until the limiter caps can be
lifted out of the carburetor body.
The basic setting must be made first
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176RA327
after removing the limiter caps!
Proceed as follows:
– Open the high speed screw H
one full turn.
– Open the low speed screw L
one full turn.
– Set the idle speed to 2,500 rpm
with the low speed screw L
– Fit the limiter caps if a tachometer
is not available (see step 6).
Precision adjustment
– Check air filter and clean or
replace it if necessary.
– Check the spark arresting screen
if installed and clean or replace it
if necessary.
– Check chain tension.
– Warm up the engine.
Adjust idle speed with a tachometer.
Adjust specified engine speeds
within tolerance of +/- 200 rpm.
1. Adjust engine speed with idle
speed screw (LA) to 3,300 rpm.
2. Turn low speed screw (L)
clockwise or counterclockwise
to obtain maximum engine
speed.
If this speed is higher than
3,700 rpm, abort the procedure and
start again with step 1.
3. Use the idle speed screw (LA)
to set engine speed again to
3,300 rpm.
4. Set the engine speed to
2,500 rpm with the low speed
screw (L).
5. Set the maximum speed to
13,500 rpm with the high speed
screw H.
6. Install new limiter caps, noting
that the stop lugs on the limiter
caps must line up with the
openings in the carburetor.
Used limiter caps must not be
reused as they may be damaged.
Always use new limiter caps!
12.4.2 Basic Setting
(carburetor with limiter
cap)

Stihl MS 440 Specifications

General

Displacement	70.7 cc
Chain Pitch	3/8"
Ignition system	Electronic
Starter	Recoil starter
Vibration reduction	Anti-vibration system
Weight (without bar and chain)	6.4 kg
Fuel tank volume	0.73 L
Oil Capacity	0.36 L
Guide Bar Length	40-63 cm
Guide Bar Length (recommended)	40-71 cm (16-28 in)