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HOMESERVICE MANUALSMERCURY1966COMET NOT AVAILABLE, 3.3L ENG VIN T, NOT AVAILABLE TRANSREPAIR AND DIAGNOSISENGINE PERFORMANCEFUEL DELIVERYFORD (AUTOLITE) 4-BARREL MODELS 4300DESCRIPTIONNOTES

1966 Mercury Comet Not Available, 3.3L Eng VIN T, Not Available Trans

Ford (AUTOLITE) 4-Barrel Models 4300: Description: Notes

1966 Mercury Comet Not Available, 3.3L Eng VIN T, Not Available TransSECTION Notes

Model 4300 carburetors are new design 3-piece body (air horn, main body, throttle body) 4-barrel carburetors with single fuel bowl for all barrels (concentric bowl with double float). Primary section has "idle air by-pass system" for idle speed adjustment (no throttle stopscrew) and a thermostatic type hot idle compensator (located on top of air horn between secondary barrels). Secondary section has spring-loaded air valves (located above secondary throttle valves) and are linked to a hydraulic dashpot to prevent air valve flutter or erratic operation. Secondary throttle valves are mechanically operated by the primary throttle linkage. This carburetor has the usual conventional fuel systems.

CARBURETOR ADJUSTMENT SPECIFICATIONS

Ford Carb. Number

Idle Speed (Engine RPM)

Float Level

Fuel Bowl Vent Valve

Choke Valve Pull-down

Fast Idle Cam Clearance

Unloader Setting

Automatic Choke Setting

Hot ⁽¹⁾

Fast ⁽²⁾

Primary Valve

Auxiliary Valve

C6AF-9510-BU

475

1200

25/32"

1/16"

.110-.130"

.080-.100"

.135"

Index

C7AF-9510-A

575

1200

25/32"

1/16"

.200-.220"

.090-.110"

.135"

Index

C7AF-9510-B

475

1200

25/32"

1/16"

.110-.130"

.080-.100"

.135"

Index

C7AF-9510-F

600

1400

25/32"

1/16"

.190-.210"

.090-.110"

.135"

Index

C7AF-9510-J

475

1200

25/32"

1/16"

.110-.130"

.080-.100"

.135"

Index

C7AF-9510-K

550

1500

25/32"

1/16"

.190-.210"

.090-.110"

135"

Index

C7AF-9510-L

625

1300

25/32"

1/16"

.200-.220"

.090-.110"

.135"

Index

C7AF-9510-M

550

1500

25/32"

1/16"

.190-. 210"

.090-.110"

.135"

Index

C7AF-9510-AC

600

1200

25/32"

1/16"

.190-.210"

.090-.110"

.135"

Index

C7AF-9510-AD

575

1400

25/32"

1/16"

.190-.210"

.090-.110"

.135"

Index

C7AF-9510-AE

575

1200

25/32"

1/16"

.200-.220"

.090-.110"

.135"

Index

C7AF-9510-AF

475

1200

25/32"

1/16"

.110-.130"

.080-.100"

.135"

Index

C7AF-9510-AG

625

1500

25/32"

1/16"

.190-.210"

.090-.110"

.135"

Index

C7AF-9510-AH

550

1500

25/32"

1/16"

.190-.210"

.090-.110"

.135"

Index

C7AF-9510-AV

475

1200

25/32"

1/16"

.070"

.110-.130"

.080-.100"

.135"

Index

C7AF-9510-AY

550

1500

25/32"

1/16"

.070"

.110-.130"

.080-.100"

.135"

Index

C7AF-9510-BH

550

1200

25/32"

1/16"

.070"

.090-.110"

.070-.090"

.100"

Index

C7AF-9510-BJ

475

1200

25/32"

1/16"

.070"

.090-.110"

.070-090"

.100"

Index

C7DF-9510-C

625

1400

25/32"

1/16"

.140-.160"

.090-.110"

.135"

Index

C7DF-9510-D

550

1600

25/32"

1/16"

.090-.110"

.090-110"

135"

Index

C7DF-9510-L

600

1400

25/32"

1/16"

.140-.160"

.090-.110"

.135"

Index

C7DF-9510-M

525

1600

25/32"

1/16"

.090-.110"

.135"

Index

C7MF-9510-A

575

1200

25/32"

1/16"

.200-.220"

.090-110"

135"

Index

C7MF-9510-B

550

1500

25/32"

1/16"

.190-.210"

.090-.110"

.135"

Index

C7MF-9510-C

625

1300

25/32"

1/16"

.190-.210"

.090-.110"

.135"

Index

C7MF-9510-D

550

1500

25/32"

1/16"

.190-.210"

.090-.110"

.135"

Index

C7MF-9510-E

550

1200

13/16"

1/16"

.160-.180"

.130-.150"

100"

Index

C7OF-9510-H

550

1500

25/32"

1/16"

.190-210"

.090-.110"

.135"

Index

C7OF-9510-S

475

1400

25/32"

1/16"

.190-.210"

.090-.110"

.135"

Index

C7OF-9510-AH

550

1200

25/32"

1/16"

.070"

.090-.110"

.070-.090"

..........

Index

C7OF-9510-AJ

475

1200

25/32"

1/16"

.070"

.090-.110"

.070-090"

..........

Index

XF-177753

550

1500

25/32"

1/16"

.110-.130"

.090-.110"

.135"

Index

⁽¹⁾	Headlights ON. Air Conditioner ON. Automatic Transmission in DRIVE.

⁽²⁾	With fast idle speed screw on kick-down step of fast idle cam.

RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.
• Brakes feel soft, pull hard to one side, or make grinding noises.
• The engine overheats, stalls repeatedly, or misfires under load.
• You are missing required tools, torque specs, or safe lifting equipment.
• You are not confident in the next step or safety outcome.