Caterpillar R3

Last Updated: July 2024

Overview

The Caterpillar R3 tractor is equipped with a 4-cylinder gasoline engine with a displacement of 350 cubic inches and liquid cooling. Key engine specifications include a bore of 4.5 inches, stroke of 5.5 inches, rated RPM of 1100, and a maximum brake horsepower of 41.99 HP at 1301 RPM. It has a gear transmission with 3 forward and 1 reverse gears. Additional details from independent testing show an Ensign Model governor, GR magneto, Ensign Model F 11/44" carburetor, and valve diameters of 1.58" inlet and 1.76" exhaust. The clutch is a single plate operated by hand lever. Track specifications are 29 clouts integral with 16x2" shoes per track with no extension rims.

Key Specifications

Transmission: Gear

Fuel Type: Gasoline

Technical Specifications

Engine

Manufacturer: Caterpillar
Model: -
Cooling Type: Liquid-cooled
Cylinder Orientation: -
Valve Configuration: -
Fuel Type: Gasoline
Induction Type: -
Cylinders: 4
Displacement (ci): 350
Bore (in): 4.5
Stroke (in): 5.5
Rated RPM: 1100
Power Output (hp): -

Transmission

Type: Gear
Forward Gears: 3
Reverse Gears: 1
Total Gears: -

Dimensions

Length (in): -
Width (in): -
Height (in): -
Operating Weight (lb): -

Power Take-Off (PTO)

PTO Type: -
PTO Speed 1 (rpm): -
PTO Speed 2 (rpm): -
PTO Speed 3 (rpm): -

Miscellaneous

Chassis: -
Drive Type: -
Steering Type: -
Coolant Capacity (qts): -
Front Tire Diameter (in): -
Front Tire Width (in): -
Rear Tire Diameter (in): -
Rear Tire Width (in): -
Front/Rear Rim Diameter (in): -
Tire Type: -
Manufacture - End Year: -
Hitch Type: -
Hitch Category: -
Hitch Position: -
Hitch Capacity (lb): -
Operator Station Type: -
Starter Type: -
Brake Type: -
Hydraulic System Type: -

Test Results

Nebraska Tractor Test Laboratory - Test Date: September 26 to October 15, 1931

Maximum Power and Fuel Consumption

Maximum Power (Brake Horsepower Test): 41.99 HP at 1301 rpm
Fuel Consumption at Maximum Power: 1.933 Gal/hr with a brake specific fuel consumption (BSFC) of 0.46 lb/HP.hr
Rated Load Test: 37.51 HP at 1304 rpm with 4.147 Gal/hr fuel consumption

Drawbar Performance

Power (Second Gear, Rated Load Test): 27.80 HP with a drawbar pull of 4180 lbs and a speed of 2.49 mph
Fuel Consumption: 1.034 Gal/hr with a drawbar fuel efficiency of 6.89 lb/HP.hr

Torque and Engine Performance

Engine Speed for Maximum Power: 1301 rpm
Water Temperature at Maximum Power: 182°F

Hydraulic Performance

The test report did not include data specific to hydraulic performance metrics for the Caterpillar R3 model.

Overall Efficiency

Fuel Efficiency at Rated Load (Brake Horsepower Test): 0.46 lb/HP.hr
Overall Fuel Consumption (Varying Load Test): 0.601 Gal/hr with fuel efficiency of 6.89 lb/HP.hr

NTTL. (1934). Test 227: Caterpillar Model R3. Nebraska Tractor Test Laboratory. University of Nebraska-Lincoln. Retrieved from https://digitalcommons.unl.edu/tractormuseumlit/834