FS 110, FS 110 R
English
37
The carburetor comes from the factory 
with a standard setting.
This setting provides an optimum fuel-air 
mixture under most operating 
conditions.
With this carburetor it is only possible to 
adjust the high speed and low speed 
screws within fine limits. 
Standard Setting
N Shut off the engine.
N Mount approved cutting tool or 
attachment.
N Check the air filter and clean or 
replace as necessary.
N Check that the throttle cable is 
properly adjusted – readjust if 
necessary – see chapter on 
"Adjusting the Throttle Cable".
N Check the spark arresting screen 
and clean or replace as necessary.
N Carefully turn both adjusting screws 
counterclockwise as far as stop: 
– The high speed screw (H) is 3/4 turn 
open. 
– The low speed screw (H) is 3/4 turn 
open.
N Start and warm up the engine.
N Adjust idle speed with the idle speed 
screw (LA) so that the cutting 
attachment does not move.
Fine Tuning
A slight correction of the setting of the 
high speed screw (H) may be necessary 
if engine power is not satisfactory when 
operating at high altitude, sea level or 
after changing the working tool.
Rule of thumb:
Turn the high speed screw (H) about 
one quarter of a turn for every 3300 ft 
(1000 m) change in altitude.
Conditions for adjustment
N Carry out the standard setting 
without disturbing the high speed 
screw (H).
N Warm up the engine for about 3 
minutes.
N Open the throttle wide.
At high altitude
N Turn the high speed screw (H) 
clockwise (leaner), no further than 
stop, until there is no further 
noticeable increase in engine 
speed.
At sea level
N Turn the high speed screw (H) 
counterclockwise (richer), no further 
than stop, until there is no further 
noticeable increase in engine 
speed.
It is possible that maximum engine 
speed may be reached with the standard 
setting in each case.
Readjust idle
It is usually necessary to change the 
setting of the idle speed screw (LA) after 
every correction to the low speed 
screw (L).
N Warm up the engine for about 3 
minutes.
Adjusting the Carburetor