CLEANING AND INSPECTION - TM-10-3930-607-150077

FUEL

away from casting without tipping. Use plug extractor

5. Float Axle: Replace if any wear can be visually

for the accelerating jet channel plugs.

Remove

detected on the bearing surface.

corrosion, dirt or gum from the four passages after the

6. Fuel Valve Seat and Needle Assembly: Replace

plugs are removed by using an 1/8" drill with the cutting

fuel valve seat and needle because both parts wear, and

tip ground blunt to avoid damaging the casting. Clean

may cause improper float level.

fuel bowl thoroughly with cleaning solution and rinse in

Idle Adjusting Needle and Spring: Inspect point

solvent. Remove the two throttle plate screws (43) and

of needle. This must be smooth and free of ridges.

remove the throttle plate (42) and throttle shaft lever

8. Throttle Plate: Inspect plate for burrs or

assembly (23).

damaged edges. Never clean a throttle plate with a

buffing wheel or a sharp instrument.

NOTE

9. Throttle Shaft and Lever: Replace shaft and

Threaded ends of throttle plate

lever assembly if the shaft is badly worn or if lever is

screws are riveted and must be filed

loose on shaft.

flat before removal to avoid breakage

10. Vacuum Cylinder Assembly and Power Jet

or stripping of threads in shaft. Use

Valve: Replace these parts because extent of wear

caution in this operation to avoid

cannot be determined by visual inspection. Wear can

scarring the side of the throttle body

result in poor idling and power jet action.

bore or the throttle plate. Do not

11. Choke Plate Assembly: Inspect for bends,

attempt to remove the idle port plug

burrs, or damaged edges. See that poppet valve is in

from side of throttle body.

good condition and works freely.

12. Choke Plate Shaft and Lever Assembly: Check

D. CLEANING AND INSPECTION

bearing surfaces for wear. See that shaft is straight and

that lever is tight on shaft.

1. Clean all metal parts thoroug hly with carburetor

13. Air Intake Assembly: Inspect machined surfaces

cleaning solution and rinse in solvent.

of air intake for dents, warpage or other damages.

2. Blow out all passages in the air intake assembly,

14. Air cleaner must fit tight or dirt will get into the

fuel bowl assembly and throttle body.

engine.

3. Be sure all carbon deposits have been removed

15. Fuel Bowl: Examine for loose discharge nozzle

from throttle bore and idle port. It is advisable to

bushing.

Examine inside bottom of bowl and all

reverse the flow of compressed air in all passages to

passages for evidence of corrosion (Metallic oxides) or

insure removal of all dirt. Never use a wire or drill to

gum deposits.

clean out Jets.

16. Gaskets: Replace all gaskets and fibre washers

4. Float Assembly: Replace float assembly if

every time the carburetor is disassembled.

loaded with gasoline, damaged, or if float axle bearing is

worn excessively. Inspect top side of float hinge for

wear where it contacts fuel valve needle.

B-40