International Harvester 666

The International Harvester 666 is a tractor produced by International Harvester. It is equipped with a 291 ci 4.8 L engine. The rated power output is 75 hp 55.9 kW. Transmission: Torque-Amplifier. Operating weight: 6780 to 7420 pounds.

Overview

	1972 - 1976 Row-Crop tractor
1972 - 1976
Row-Crop tractor

Production
Manufacturer	International Harvester
Row-Crop tractor
Built in Rock Island, Illinois, USA
Total built	9,367
Original price	$11,875
Torque amplifier was an option. In 1973, the hydrostatic version of the 666 was renamed the 70 Hydro.

International Harvester 666 Power
Engine (gross)	75 hp 55.9 kW
Drawbar (claimed)	57 hp (gear) 42.5 kW
	54 hp (hydro) 40.3 kW
PTO (claimed)	65 hp (gear) 48.5 kW
	69 hp (hydro) 51.5 kW
Drawbar (tested)	58.01 hp 43.3 kW
PTO (tested)	69.61 hp 51.9 kW
Performance test details ...

Mechanical
Two-wheel drive
Power steering
Dry disc brakes
Open operator station. Two-post ROPS or canopy optional. Cab available with air-conditioning.

Hydraulics
Type	open center
Pump flow	12 gpm 45.4 lpm

Tractor hitch
Rear Type	II
Type	IH Fast Hitch

Power Take-off (PTO)
Rear PTO	independent
Rear PTO Type	540 (1.375)

Dimensions & Tires
Wheelbase	103 inches 261 cm
Weight	6780 to 7420 pounds
Front tire	7.50-16
Rear tire	15.5-38
Full dimensions and tires ...

Electrical
Charging system	alternator
Battery volts	12

References
Farm Equipment Reference Catalog published in 1972, by International Harvester

Engine

Engine options
International Harvester 5.1L 6-cyl diesel
International Harvester 4.8L 6-cyl gasoline

Engine Detail — 312 ci / 5.1 L Diesel

Manufacturer	International Harvester D312
Fuel Type	Diesel
Configuration	6-cylinder, liquid-cooled
Displacement	312 ci 5.1 L
Bore/Stroke	3.875x4.410 inches 98 x 112 mm
Power (gross)	75 hp 55.9 kW
Fuel system	direct injection
Air cleaner	dual stage dry
Compression	17:1
Rated RPM	2000
Starter volts	12
Coolant capacity	21 qts 19.9 L

Engine Detail — 291 ci / 4.8 L Gasoline

Manufacturer	International Harvester C291
Fuel Type	Gasoline
Configuration	6-cylinder, liquid-cooled
Displacement	291 ci 4.8 L
Bore/Stroke	3.75x4.39 inches 95 x 112 mm
Power (gross)	75 hp 55.9 kW
Air cleaner	dual stage dry
Compression	7.5:1
Rated RPM	2000
Starter volts	12
Coolant capacity	21 qts 19.9 L

Transmission

Transmission options
5-speed
hydrostatic
10-speed two-speed power shift

Transmission — sliding gear

Transmission	sliding gear
Gears	5 forward and 1 reverse

Transmission — infinite forward and reverse hydrostatic

Type	hydrostatic
Gears	infinite forward and reverse

Transmission — Torque-Amplifier

Transmission	Torque-Amplifier
Type	two-speed power shift
Gears	10 forward and 2 reverse
Clutch	dry disc

Dimensions

International Harvester 666 Tires
Ag front	7.50-16
Ag rear	15.5-38

Dimensions
Wheelbase	103 inches 261 cm
Length	161 inches 408 cm
Width	87 inches 220 cm
Height (steering wheel)	77 inches 195 cm
Shipping weight	6780 lbs (gas gear) 3075 kg
	7420 lbs (diesel hydro) 3365 kg
Clearance (front axle)	21 inches 53 cm
Clearance (drawbar)	14 inches 35 cm
Front tread	50 to 74 inches 127 to 187 cm
Front tread	56 to 80 inches 142 to 203 cm
Rear tread	50 to 96 inches 127 to 243 cm

Tests

Tractor Tests
NTTL 1151: 312 diesel Torque Amplifier 2WD
NTTL 1152: gasoline Torque Amplifier 2WD
NTTL 1154: gasoline hydrostatic 2WD
NTTL 1155: diesel hydrostatic 2WD

Nebraska Tractor Test 1151
312 diesel Torque Amplifier 2WD November 3 - 14, 1973 Link: Nebraska Tractor Test 1151 file
PTO performance
Power at rated engine speed	66.29 hp 49.4 kW
Fuel use	4.7 gal/hour 17.8 l/hour
Drawbar performance
Max power	58.01 hp 43.3 kW
Fuel use	4.6 gal/hour 17.4 l/hour
Gear 3-Direct used for power test.
Max pull	8,012 lbs 3634 kg
Gear 2-TA used for pull test.

Nebraska Tractor Test 1152
Gasoline Torque Amplifier 2WD November 5 - December 3, 1973 Link: Nebraska Tractor Test 1152 file
PTO performance
Power at rated engine speed	66.30 hp 49.4 kW
Fuel use	12.0 gal/hour 45.4 l/hour
Drawbar performance
Max power	57.29 hp 42.7 kW
Fuel use	5.7 gal/hour 21.6 l/hour
Gear 3-Direct used for power test.
Max pull	7,981 lbs 3620 kg
Gear 2-TA used for pull test.

Nebraska Tractor Test 1154
Gasoline hydrostatic 2WD November 14 - December 3, 1973 Link: Nebraska Tractor Test 1154 file
PTO performance
Power at rated engine speed	69.61 hp 51.9 kW
Fuel use	6.9 gal/hour 26.1 l/hour
Power at rated PTO speed	64.10 hp 47.8 kW
Fuel use	5.8 gal/hour 22.0 l/hour
Drawbar performance
Max power	53.86 hp 40.2 kW
Fuel use	7.7 gal/hour 29.1 l/hour
Max pull	8,427 lbs 3822 kg

Nebraska Tractor Test 1155
Diesel hydrostatic 2WD November 14 - December 3, 1973 Link: Nebraska Tractor Test 1155 file
PTO performance
Power at rated engine speed	69.51 hp 51.8 kW
Fuel use	5.6 gal/hour 21.2 l/hour
Power at rated PTO speed	65.41 hp 48.8 kW
Fuel use	5.3 gal/hour 20.1 l/hour
Drawbar performance
Max power	53.10 hp 39.6 kW
Fuel use	5.6 gal/hour 21.2 l/hour
Max pull	8,310 lbs 3769 kg

Photos

International Harvester 666 tractor photo