International Harvester Company INTERNATIONAL Cub Cadet 73 Operator's Manual page 12

FUEL SYSTEM
Carburetor and fuel strainer
I. Governor control rod
Z Idle odjustment screw
3. Throttle stop screw
4. High speed adjustment screw
Mlust. 10
(International Cub Cadet 73 Tractor)
5« Fuel shut*oH valve
6» Sediment bowl
7. Fuel line
6. Air cleaner
lllust. 10A
(Intemotionol Cub Codet 106, 107, 126, 127,
ond 147 Tractors)
Adjusting the Idle Adjustment Screw
After the high speed adjustment screw is
adjusted, it may be necessary to readjust the
idle adjustment screw (IHusts 10 ond 10A), as
each affects the other.
Close the idle adjustment screw to its seat
by turning it clockwise; then open it one turn.
Start the engine and operate it at fast idling
speed (without any load) until thoroughly warm.
While the engine is running at fast idle
speed, it is advisable to screw in the throttle
stop screw(Mlusts. 10 ond 10A)a few turns to keep
the engine from stopping when the throttle
lever is moved to the fully retarded "SLOW"
position. The engine will then be idling at a
fairly high speed and the throttle stop screw
can be backed out a little at a time until the
desired idle speed is obtained.
If the engine misses or rolls while backing
out the throttle stop screw, the idle adjustment
screw may be adjusted in or out until the en¬
gine operates smoothly. Speed up the engine
for a few seconds; then recheck the idle ad-
justment, A slight adjustment in or out will
give the smoothest idle.
Adjusting the High*Speed Adjustment Screw
Turn the high speed adjustment screwdllusts.
ID and 10A) counter-clockwise approximately two
turns from the closed position and start the
engine.
After the engine has reached normal oper¬
ating temperature, accelerate the engine and
check its response.
Place the engine under load and turn the high
speed adjustment screw (lllusts. 10
and
10A)to the
leanest mixture that will allow satisfactory
acceleration and steady governor operation.
If the engine misses and backfires under
load, the high speed mixture is too lean. The
high speed adjustment screw must be turned
counter-clockwise 1/4 turn at a time until the
condition is corrected.
If the engine shows a sooty exhaust and is
alugglsh under load, the high speed mixture is
too rich. The high speed adjustment screw
must be turned clockwise
1/4
turn at a time
until the condition is corrected.
10