1. Carburetor Adjustments
The carburetor is adjusted at the factory and under
normal operating conditions will not require
readjusting. If readjustment is necessary because
of fuel and air conditions, the following procedure is
recommended:
a. Turn high speed adjustment screw (D, Fig. 4)
counter-clockwise two turns from closed position
and start engine.
b. After engine has reached normal operating
temperature, accelerate and check response.
Place engine under full load and adjust high
speed adjustment screw for leanest mixture that
will still allow satisfactory acceleration and
Figure 2
steady governor operation.
K141 Engine with Dry Type Air Cleaner
c. If engine misses and backfires under full load,
high speed mixture is too lean. The high speed
A - "STOP" Button
D - Fuel Shut-off Valve
adjustment
screw
must
be
turned
B - Choke Lever
E - Starter Pulley
counterclockwise 1/4 turn at a time until
C - Dry Type Air Cleaner
F - Cooling Air Screen
condition is corrected.
d. If engine shows sooty exhaust and is sluggish
The paper element should be handled with care to
under full load, high speed mixture is too rich.
avoid perforations. Removing the dirt with compressed
The high speed adjustment screw must be
air can rupture the paper element.
turned clockwise 1/4 turn at a time until
condition is corrected.
The time between changes will vary with air
conditions. Check to ensure that gasket surfaces of
e. Final check of high speed adjustment; operate
element are not bent or damaged in any way. Gasket
engine under full load and make any corrections
surfaces must seal tightly at top and bottom of cleaner
necessary for smooth operation.
shell to prevent foreign matter from entering the
f. Idle adjustment screw
(A, Fig. 4)
carburetor.
adjustments should be made at the same time
as high speed adjustment screw adjustments, as
Whenever air cleaner is removed, cover air intake
each effects the other.
hole to prevent dirt from falling into air horn or
carburetor. The gasket between air horn and carburetor
g. The final idle adjustment should be made at an
must fit tightly to prevent unfiltered air from entering
engine speed of not less than 1000 RPM.
carburetor.
Adjust until smoothest idle is obtained.
FUEL SYSTEM
Warning:
Service difficulties with fuel systems usually originate
Do not use force on high speed
from improper carburetor adjustments or dirt in one of
adjustment screw or idle mixture
the components. If gum forms in the components it
screw---they will be damaged.
will be necessary to completely disassemble and
thoroughly clean the carburetor.
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