Case 446 User Manual

CARBURETOR
The carburetor has three simple adjustments:
1. Main iuel adjustment
2. Idle fuel adjustment
3. Idle speed adjustment
MAIN FUEL AND IDLE FUEL ADJUSTMENT
IMPORTANT : Needle valves may be damaged by turning them
in too far or forcing them against their seats.
1. Before starting the engine, adjust main fuel adjustment screw on carburetor 1·3/8 to
1·1/2 tu rns open from seat .
2.
Adjust idle fuel adjustment screw on carburetor 1 turn open from seat.
3. Run engine
to warm up to operating temperature.
4. Adjust throttle to 3,000 RPM,Load to 2800 RPM.
5.
Adjust main fuel adjustment screw to achieve maximum RPM at this throttle sett ing.
6.
Reduce load and adjust throttle setting to 1200 RPM .
7.
Adjust the idle fuel adjustment screw to achieve the maximum RPM at this throttle
setting.
DO
NOT readjust main fuel adjustment at this time . This sequence m..:st be followed
because in middle speed ranges there is interaction between the main and idle fuel
adjustments.
LOWSPEEDSET ______________ ~
SET LOW SPEED ADJUSTMENT
ON GOVERNOR
MAIN
FUEL
SO ENGINE RUNS AT 1200 RPM
LINKAGE· (0 .8 mm)
(HIGH SPEED)
IN "SLOW" POSITION
GAP
HERE AT NO
lOAD~
THROTTLE
STOP
SCREW
SIDE VIEW
f4jMENT
IDLE
ADJUSTMENT
REAR VIEW
LOW SPEED ADJUSTMENT
FIGURE 19
h CAUTION: Do not change the engine governor settings or over·
.. speed the cngillc.
IDLE
SPEED ADJUSTMENT
Put the throttle lever in the "Slow" position. Turn the slow speed ' adjustment screw
in to increase idling speed and out to decrease idling speed until 1200 RPM is obtained.
Set the throttle stop screw (located on carburetor throttle lever) with no load con ·
nected and while running at low speed setting . Turn the screw to give approximately 1/32
inch (0.8 mm) clearance between the scr ew and pin.
·
32 ·

Case 446 Specifications

General

Brand	Case
Model	446
Category	Tractor
Language	English