Autolite Model 4300 Carburetor Operation, Adjustment, and Overhaul Training

The Autolite Model 4300 Carburetor was a popular carburetor used on many Ford and Mercury vehicles from the 1950s to the 1970s. It is a single-barrel, down-draft carburetor that is known for its reliability and ease of adjustment.

Carburetor Components

The Autolite Model 4300 Carburetor consists of the following components:

Autolite Model 4300 Carburetor - Operation, Adjustment and Overhaul; Training Handbook 9503.1, 9503.2; Vol. 67 S2 L2

by William Morris

4.1 out of 5

Language	:	English
File size	:	20325 KB
Screen Reader	:	Supported
Print length	:	192 pages
X-Ray for textbooks	:	Enabled
Hardcover	:	340 pages
Item Weight	:	1.33 pounds
Dimensions	:	5.98 x 0.81 x 9.02 inches

FREE

• Carburetor body
• Float bowl
• Float
• Needle and seat
• Main jet
• Idle jet
• Air bleed
• Throttle valve
• Choke valve

Fuel Flow

Fuel flows into the carburetor through the fuel inlet and into the float bowl. The float bowl is a reservoir that holds a supply of fuel for the carburetor. The float is a hollow ball that floats on the surface of the fuel in the float bowl. As the fuel level in the float bowl rises, the float rises and presses against the needle and seat, shutting off the flow of fuel into the float bowl.

Air Flow

Air flows into the carburetor through the air cleaner and into the venturi. The venturi is a constriction in the air passage that causes the air to speed up. As the air speeds up, it creates a vacuum that draws fuel out of the main jet and into the air stream. The amount of fuel that is drawn out of the main jet is controlled by the position of the throttle valve.

Idle Speed Adjustment

The idle speed is adjusted by turning the idle speed screw. The idle speed screw is located on the side of the carburetor. Turning the idle speed screw clockwise will increase the idle speed, and turning the idle speed screw counterclockwise will decrease the idle speed.

Mixture Adjustment

The mixture is adjusted by turning the mixture screw. The mixture screw is located on the side of the carburetor, below the idle speed screw. Turning the mixture screw clockwise will lean out the mixture, and turning the mixture screw counterclockwise will richen the mixture.

Troubleshooting Common Carburetor Problems

The following are some common carburetor problems and their solutions:

• Engine runs rough at idle: This could be caused by a lean mixture, a rich mixture, or a vacuum leak.
• Engine hesitates when accelerating: This could be caused by a lean mixture, a clogged fuel filter, or a weak fuel pump.
• Engine stalls when coming to a stop: This could be caused by a lean mixture, a dirty carburetor, or a worn-out throttle shaft.

Overhaul Procedures

If the carburetor is not functioning properly, it may need to be overhauled. The following are the steps involved in overhauling an Autolite Model 4300 Carburetor:

1. Remove the carburetor from the engine.
2. Disassemble the carburetor.
3. Clean all of the carburetor components.
4. Inspect all of the carburetor components for wear or damage.
5. Replace any worn or damaged components.
6. Reassemble the carburetor.
7. Install the carburetor on the engine.

The Autolite Model 4300 Carburetor is a reliable and easy-to-adjust carburetor. By following the instructions in this article, you can learn how to operate, adjust, and overhaul this carburetor yourself.

Autolite Model 4300 Carburetor - Operation, Adjustment and Overhaul; Training Handbook 9503.1, 9503.2; Vol. 67 S2 L2

by William Morris

4.1 out of 5

Language	:	English
File size	:	20325 KB
Screen Reader	:	Supported
Print length	:	192 pages
X-Ray for textbooks	:	Enabled
Hardcover	:	340 pages
Item Weight	:	1.33 pounds
Dimensions	:	5.98 x 0.81 x 9.02 inches

FREE