REMOVAL - TM-10-3930-644-14-P0227

TM 10-3930-644-14&P

When the engine has obtained normal operating

9. Use a small screwdriver and force throttle shaft

temperature the choke valve must be fully

packing retainer from throttle body. Remove

opened to assure maximum power and

packing and retainer cup.

economy. In addition, extended use of the

choke results in more gasoline being supplied to

10. Remove nozzle plug, power jet, nozzle gasket

the engine than can be burned.

A large

and O-ring and remove nozzle from bottom of

percentage of the unburned gasoline is lost

bowl.

through the exhaust system. The remainder of

the raw gasoline is forced between the pistons

11. Remove choke valve screws and remove choke

and cylinder walls, washing away the protective

valve from choke shaft. Remove choke shaft.

oil film and increasing engine wear. It then

enters the crankcase where it dilutes the engine

12. Remove screws attaching choke bracket to fuel

oil.

bowl neck and remove bracket.

Remove

packing from bracket.

Any adjustments that are necessary on the

carburetor should never be attempted until the

E. INSPECTION AND REPAIR

engine has obtained its normal operating

temperature and the choke valve has been

1. Inspect float valve for grooved condition and

placed in the wide open position.

damage. If valve is damaged, replace float

valve and float valve seat.

C. REMOVAL

2. Replace idle adjusting needle if grooved or

1. Disconnect choke wire and throttle cable from

damaged.

carburetor.

Disconnect governor rod from

carburetor. Loosen clamps and disconnect air

3. Replace throttle shaft and lever assembly if

cleaner hose from carburetor.

looseness is noted between shaft and throttle

body.

2. Close fuel shutoff cock at fuel tank. Disconnect

Fuel Inlet line from carburetor.

4. Replace all packings and gaskets.

3. Remove two nuts and lockwashers securing

5. A repair kit is available for the carburetor. It is

carburetor to manifold. Remove carburetor and

recommended that kit parts be installed in place

gasket. Remove studs from carburetor only if

of old parts whenever the carburetor is

necessary.

overhauled.

D. DISASSEMBLY

F. REASSEMBLY

1. Install new packing and retainer on throttle shaft

1. Remove drain plug and drain fuel bowl.

and lever assembly. Insert shaft in carburetor

Remove four screws attaching throttle body (Fig.

and tap lightly until retainer is flush with casting

4-6) to fuel bowl.

face.

2. Raise throttle body and separate gasket from

2. Install throttle valve on shaft with identification

fuel bowl flange. Carefully lift throttle body from

mark on valve facing flange face of carburetor.

full bowl, being careful not to damage float

Tap valve lightly to center in throttle bore.

assembly.

Tighten screws securely.

3. Remove float axle shaft and remove float from

3. Install economizer jet and idle jet.

throttle body.

4. Install idle adjusting needle and spring. T rn

4. Remove float valve from throttle body. Remove

needle all the way in to seat then back off

bowl gasket and venturi.

approximately one turn for preliminary setting.

5. Remove float valve seat and seat gasket.

5. Place a new gasket on float valve seat and

install float valve seat and float valve.

6. Remove economizer jet and idle jet.

6. Place new. throttle body to fuel bowl gasket on

7. Remove idle adjusting needle and spring.

throttle body and install venturi.

8. Remove throttle valve screws, throttle valve and

throttle shaft and lever assembly .

R-123-1

3-62