Stihl BR 500 - Adjusting the Carburetor; User Adjustment

25BR 500, BR 550, BR 600
– Use a new screw and coat it with
Loctite.
: Fit the throttle shutter (1) and
tighten it down moderately,
b 3.4
Check that the stamped digits
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(arrow) face up.
– Check that the notch in the
throttle shutter lines up with the
bores (arrows) in the carburetor
body.
: Loosen the screw (1) slightly.
– Center the throttle shutter so that
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it moves freely.
: Tighten down the screw (1).
– Check that shutter still moves
freely.
Install all other parts in the reverse
sequence.
Standard setting
Do not remove the limiter caps to
carry out the standard setting.
– With this carburetor it is only
possible to correct the setting of
the high speed screw (H) and low
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speed screw (L) within fine limits.
Make the following adjustments:
– Turn the high speed screw (H)
counterclockwise as far as stop.
– Turn the low speed screw (L)
counterclockwise as far as stop.
– Check the air filter and replace it
if necessary, b 6.1
If the air filter is dirty, install a new
one – do not clean.
– Check adjustment of throttle
cable, b 9.3.2
– Check the spark arresting screen
(if fitted), b 7.6
– Start the engine and allow it to
warm up.
– Adjust engine idle speed.
6.4 Adjusting the Carburetor
6.4.1 User Adjustment
RA_452_00_01_02.book Seite 25 Donnerstag, 16. Februar 2012 11:52 11