TM 5-4310-227-15
d. Adjustment.
Caution:
Operating the unit with dirty
(1) Obtain the initial adjustment as fol-
fuel and no fuel strainer in the system can
lows:
result in engine stoppage and damage to the
(a) Close the idle adjustment needle
carburetor.
valve (7).
3-37. Carburetor
Caution: Do not tighten the nee-
a. Removal.
dle valve. If force is applied, dam-
(1) Loosen the screw (32, fig. 2-7) that
age to the valve and carburetor
secures the air cleaner bracket (30)
body will result.
to the carburetor (36).
(2) Disconnect the fuel pump-to-carbure-
(b) From the closed position, open the
idle adjustment needle valve three-
tor tube (9) from the elbow (8).
(3) R e m o v e the governor control rod
quarters of a turn.
(c) Close the high speed adjustment
valve (10). Observe the caution in
control and choke (para 3-40).
(4) Remove the two bolts (5) and lock-
(a) above.
(d) From the closed position, open the
washers (6) that secure the carbure-
high-speed adjustment valve one
tor (36) to the intake manifold (4).
turn.
Remove the carburetor and gasket.
(2) Start the engine (para 2-26).
(5) Remove the carburetor fuel inlet el-
bow (8).
(3) When the engine is warm, place the
b. Cleaning, Inspection, and Repair.
g o v e r n o r adjusting lever (15, fig.
(1) C l e a n the carburetor with a clean
c l o t h dampened with an approved
(4) A d j u s t the idle adjustment needle
cleaning solvent.
v a l v e (7, fig. 2-7) to a point just
(2) Inspect the carburetor for loose or
above where the engine will stall.
missing mounting bolts between the
(5) Place the governor adjusting lever in
upper and lower sections.
the operating position.
(3) Inspect the carburetor for cracks and
(6) Slowly close the high-speed adjust-
breaks. Test the throttle for excessive
ment valve (10) until the engine be-
play and freedom of movement.
gins to falter. Slowly open the high-
(4) Inspect the mounting gasket for serv-
speed adjustment valve until the en-
iceability. Replace all missing or de-
gine runs smoothly.
fective parts. Replace a defective car-
Note. The high-speed adjustment valve
buretor.
does not require frequent adjustment.
c. Installation.
Once the proper adjustment has been ob-
(1) Install the carburetor fuel inlet elbow
tained, do not readjust the valve unless
(8).
the adjustment has been disturbed.
(2) Position the carburetor (36) on the
air cleaner bracket (30) and secure
the carburetor and gasket to the in-
a. Removal and Disassembly.
take manifold (4) with the two lock-
washers (6) and bolts (5).
(1) Remove the engine air cleaner (para
(3) Install the governor control rod (para
3-6) .
(2) Disconnect the engine breather line
and choke (para 3-40).
(10, fig. 3-2) from the air cleaner
(4) Conned the fuel pump-to-carburetor
bracket breather line elbow (12).
tube (9) to the elbow (8).
(3) Remove the capscrew (18) that se-
(5) Tighten the screw (32) that secures
cures the air cleaner bracket (17) to
the air cleaner bracket (30) to the
the bracket clip (20).
carburetor.
