Carter M4503 Mechanical Fuel Pump

Carter M4503 Mechanical Fuel Pump

The Carter M4503 is a mechanical fuel pump built for OE-style fit, form, and function on a wide range of classic Chevrolet, GMC, Buick, Oldsmobile, and Pontiac applications. It is a practical replacement for carbureted vehicles that need steady fuel delivery and correct threaded outlet connection details.

• Mechanical fuel pump for carbureted air and fuel delivery systems
• Inlet type: hose, with 1 inlet and 1 threaded outlet
• Outlet fitting thread size: 1/2-20 UNF
• Minimum flow rating: 25
• Operating pressure range: 3 to 5.5
• Gasket or seal included for installation
• 2 mounting holes for OE-style attachment
• Cross-references Airtex 40446 and Delphi MF0051 for the same application

Fitment Coverage

Compatible with many classic GM vehicles, including Fits 1975 Chevrolet C10, N/A; Fits 1967-1975 Chevrolet C10 Suburban, N/A; Fits 1967-1974 Chevrolet Camaro, N/A; Fits 1970-1974 Pontiac Firebird, N/A; and Fits 1971-1975 GMC Jimmy, N/A. The M4503 also covers additional Chevrolet, GMC, Buick, Oldsmobile, and Pontiac models across 1965-1978, including Chevrolet Bel Air, Impala, Nova, and GMC van applications.

Product Details

Carter M4503 is engineered as a direct mechanical replacement for vehicles that rely on a cam-driven fuel pump. The hose-style inlet and threaded outlet support common factory-style fuel line layouts, while the included gasket or seal helps complete the installation. This part number, M4503, is a strong match for restorations and maintenance on Chevrolet C10, Camaro, and Pontiac Firebird fuel systems where correct pressure and flow matter.

Common Problems This Pump Can Address

• Hard starting caused by weak fuel delivery
• Fuel starvation under normal driving conditions
• Low fuel pressure at the carburetor
• Fuel leaks at a worn pump gasket or seal
• Poor drivability from an aging mechanical pump

Installation Notes

Verify the vehicle uses a mechanical pump and confirm the sheet metal pump with crimped style requirement noted in the fitment data before installation. Check inlet hose size, outlet thread size, and fuel line routing against the original setup. Because mounting hardware is not listed as included, reuse or source the correct hardware as needed for the application.

Quality Assurance

Carter Fuel Systems focuses on OE fit, form, and function with broad vehicle coverage and application-specific solutions. The M4503 follows that approach with a mechanical design and fitment coverage for many classic GM platforms, including Chevrolet C10, Camaro, and Pontiac Firebird applications.