TM 5-4240-501-14&P
indicating fuel is flowing into regulator. Put soap suds on
the outlet again. Then slowly turn adjusting screw at
bottom of secondary regulator counterclockwise until a
bubble forms at the outlet. Then turn adjusting screw in
(clockwise) slowly until soap bubbles on outlet no longer
form. Hold adjusting screw at this point and tighten
locknut. Press primer button to allow fuel to flow.
Release and again put soap suds on outlet to make
certain the fuel shuts off. Repeat several times. If
bubble should form after primer button is released, the
adjusting screw should be turned in until flow stops and
soap bubble does not break or enlarge. Loosen fuel line
between regulators. Reassemble secondary regulator to
carburetor with short rubber fuel line in place. Tighten
fuel line, Fig. 110.
Adjusting Carburetor, L.P. Fuel System
See Fig. 110.
Loosen locknut on load needle screw and turn needle
screw in until it seats. Do not force; open 2-1/2 turns.
Turn idle needle in until it seats, then open one turn. If
engine will not be required to idle, leave idle needle
closed. Depress the primer button momentarily, then
start engine, run engine to allow it to warm up before
final adjustment. With engine running at normal
operating speed, turn the load needle screw in slowly
(clockwise) until engine starts to miss (lean mixture).
Then turn load screw out slowly past the point of best
operation until engine begins to run unevenly (rich
mixture). Then turn load screw in just enough so engine
will run smoothly. Hold load screw and tighten locknut.
Hold throttle at idle position, then release throttle.
Engine should accelerate quickly and smoothly.
If engine will be required to run at idle, turn the idle
speed adjusting screw on throttle until engine runs at
proper idle speed for engine model. See Check Chart.
Hold throttle at this point and turn the idle slowly in or out
until engine runs at maximum idle speed. Then re-adjust
idle speed screw until proper idle speed is obtained.
Allow throttle to open. Engine should accelerate quickly
and smoothly. If not, re-adjust load screw, usually to a
richer mixture. To stop engine, turn off fuel supply valve
at fuel cylinder.
CARBURETION
L.P. Fuel and Kerosene
Fig. 110 - Adjusting Carburetor, L.P. Fuel System
Starting Engine
To start engine, do not use choke, but depress primer
button momentarily, then start engine immediately. In
cold weather, it may be necessary to partially close the
carburetor choke valve to permit the engine to run
smoothly until the engine warms up.
Cleaning L.P. Gas Filter (Optional)
Unscrew filter head from filter body. Remove element
assembly from the head. Fig. 111. Wash the element in
commercial solvent cleaner or
gasoline.
If
the
accumulated dirt is gummy, we suggest a short soaking
period in solvent cleaner. The element should then be
rinsed in clean gasoline and blown with compressed air.
ALWAYS USE REVERSE FLOW FROM THE INSIDE
OUT. NEVER USE COMPRESSED AIR ON THE
OUTSIDE SURFACE OF THE ELEMENT. NEVER DIP
ELEMENT
IN
"BRIGHT
DIP"
OR
OTHER
ACID
SOLUTION.
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