TM 5-4240-501-14&P
Fig. 105 - Assemble Fuel Pump
Install main nozzle using blunt screw driver to prevent
damage to slot and metering hole. Place bowl on
carburetor and install bowl nut and washer. Install one
(1) pump valve spring on spring boss, Fig. 106, and then
place diaphragm on carburetor. Put pump spring cup
and pump spring on diaphragm, Fig. 105. Place a pump
valve spring on spring boss in pump body, Fig. 106, and
place pump body on carburetor. Place damping
diaphragm, pump gasket and pump cover on pump body
and install three (3) screws. A fuel pump repair kit is
available, see illustrated parts list for part number.
Fig. 106 - Pump Spring Location
(Valve Flap Bent Down for Clarity)
Place choke shaft in carburetor body and slide in choke
valve with notch out and dimple down toward float bowl,
Fig. 107A. Install two (2) screws using a screw driver.
Slide in throttle shaft and then slide in throttle plate with
two (2) dimples facing toward the idle valve. When valve
is installed correctly, the dimples will be down and the
number on the plate visible with the throttle in the closed
or idle position, Fig. 107B. Install the idle and-high speed
needle valves.
CARBURETION
Cross-Over Flo-Jet
Fig. 107A-
Fig. 107B-
Carburetor Adjustments
INITIAL ADJUSTMENT - Turn idle and needle valves
clockwise until they just close, Fig. 108.
CAUTION: Valves may be damaged by turning hem in
too far.
Now
open
high
speed
needle
valve
ll/2
turns
counterclockwise and idle valve one turn. This initial
adjustment will permit the engine to be started and
warmed up prior to final adjustment.
Fig. 108 - Carburetor Adjustment
NOTE: Carburetor adjustments should be made with the
air cleaner on engine.
FINAL ADJUSTMENT PROCEDURE
Idle Valve Mixture
Place governor speed control lever in "IDLE" position.
Set idle speed adjusting screw to obtain 1750 R.P.M.
minimum while holding throttle lever again screw. Turn
idle valve in until R.P.M. slows or misses (clockwise -
lean mixture), then turn it out past smooth idling point
until engine runs unevenly (rich mixture). Now turn idle
valve to the midpoint between rich and lean so the
engine runs smoothly. Release throttle lever.
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