International Harvester Farmall A, AV, B, BN & U-2 Power Unit Service Manual 1939-1953

International Harvester Farmall A, B & U-2 Power Unit Documentation

• Covers 1939–1953 International Harvester Farmall A, AV, B, BN, International A tractors, and U-2 Power Unit, documenting engine, drivetrain, and chassis specifications
• Third-party publication originating from eBay seller Polar558, providing technical data and diagrams for maintenance and internal assembly reference
• Contains 80 detailed illustrations including exploded views of the engine, carburetor, governor, transmission, and differential assembly
• Downloads to your account within seconds of checkout
• Re-download the file any time, no expiration
• Full-text search finds any part number in seconds
• Suitable for printing individual sections for shop-floor use
• This 1939–1953 service documentation remains the primary technical archive for restoring and maintaining the International Harvester A/B series tractor range

Engine and Fuel System Architecture

This 71-page technical publication details the maintenance and assembly parameters for the 4-cylinder wet-sleeve engine used across the Farmall A, B, and U-2 Power Unit range. The documentation covers complete engine teardown procedures, including specifications for connecting rods, bearings, crankshaft tolerances, and valve train geometry. Fuel system content focuses on the Zenith and Marvel Schebler carburetor units, providing detailed breakdown and reassembly data alongside jet identification charts for various fuel types, including gasoline, kerosene, and distillate options.

Drivetrain, Electrical, and Dimensional Data

Transmission and Specification Highlights

Technical data within the publication includes detailed transmission speed charts, electrical wiring schematics for starter and generator systems, and comprehensive cooling system capacities. The transmission section highlights bevel gear adjustment procedures, including tooth contact patterns for proper pitch line intersection. Cylinder head bolt torque is documented at 65 ft. lb. in the engine specification tables. The intake valve stem clearance is specified at 0.0015–0.0035 inches in the valve guide data section. Cooling system capacity for these units is documented at 3-3/8 gallons.

Note: This page is a contents overview for the manual. It does not provide repair or diagnostic instructions. An official-format service publication covering the 1939–1953 International Harvester Farmall A, AV, B, BN, International A, and U-2 Power Unit, documenting complete engine, chassis, electrical, and fuel-system specifications for these classic tractors.