David Brown 990 Implematic

The David Brown 990 Implematic is a tractor produced by David Brown. It is equipped with a 185.8 ci 3.0 L engine. The rated power output is 52 hp 38.8 kW. Transmission: 12 forward and 4 reverse. Operating weight: 4272 to 4312 pounds.

Overview

	1961 - 1980 Model year 1961-19651965-19701971-1980 Utility tractor
1961 - 1980
Model year 1961-19651965-19701971-1980
Utility tractor

Production
Manufacturer	David Brown
Utility tractor
Built in Meltham Mills, Huddersfield, England

David Brown 990 Engine
David Brown 3.0L 4-cyl diesel
Fuel tank	13.74 gal 52.0 L
Engine details ...

David Brown 990 Power
Engine	52 hp 38.8 kW
Drawbar (claimed)	43 hp 32.1 kW
PTO (claimed)	48 hp 35.8 kW
Drawbar (tested)	43.47 hp 32.4 kW
PTO (tested)	51.60 hp 38.5 kW
Performance test details ...

Mechanical
Two-wheel drive
Differential lock	mechanical rear
Steering	manual
	hydrostatic power (optional)
Differential mechanical expanding shoe brakes
Open operator station.

Hydraulics
Type	open center
Pressure	2000 psi 137.9 bar
Total flow	7.4 gpm 28.0 lpm

Tractor hitch
Rear Type	II/I

Power Take-off (PTO)
Rear PTO	transmission
	live (optional)
Clutch	dry disc
Rear PTO Type	540/1000 (1.375)
Engine RPM	540@1800 (Low)
	540@1100 (High)
	1000@2000

Dimensions & Tires
Wheelbase	76.75 inches 194 cm
Weight	4272 to 4312 pounds
Front tire	6.00-16
Rear tire	11-32
Full dimensions and tires ...

Electrical
Charging system	generator
Batteries	2
Battery volts	6

Engine

Engine Detail — 185.8 ci / 3.0 L Diesel

Manufacturer	David Brown
Fuel Type	Diesel
Configuration	4-cylinder, liquid-cooled
Displacement	185.8 ci 3.0 L
Bore/Stroke	3.625x4.50 inches 92 x 114 mm
Power	52 hp 38.8 kW
Air cleaner	oil bath
Compression	17:1
Rated RPM	2200
Operating RPM	700-2200
Starter volts	12
Oil capacity	7.8 qts 7.4 L
Coolant capacity	14.4 qts 13.6 L

Transmission

Transmission options
6-speed gear
12-speed partially synchronized

Transmission — 6 forward and 2 reverse gear

Type	gear
Gears	6 forward and 2 reverse
Clutch	279mm dry disc
Three gears (1-3) plus reverse (R) in low and high ranges.

Transmission — 12 forward and 4 reverse partially synchronized

Type	partially synchronized
Gears	12 forward and 4 reverse
Twelve-speed transmission introduced in 1963.

Dimensions

David Brown 990 Tires
Standard tires (ag)	Front: 6.00-16. Rear: 11-32

Dimensions
Wheelbase	76.75 inches 194 cm
Length	118 inches 299 cm
Width	67 inches 170 cm
Height (hood)	56 inches 142 cm
Clearance (front axle)	20 inches 50 cm
Front tread	52/56/60/64/68/72/76 inches 132/142/152/162/172/182/193 cm
Rear tread	52/56/60/64/68/72/76 inches 132/142/152/162/172/182/193 cm

David Brown 990 Weight
Operating	4272 lbs 1937 kg
	4312 lbs (live PTO) 1955 kg
Ballasted	5880 lbs 2667 kg

Tests

Nebraska Tractor Test 903
3L diesel 6-speed 2WD June 11 - 19, 1965 Link: Nebraska Tractor Test 903 file
PTO performance
Power at rated engine speed	51.60 hp 38.5 kW
Fuel use	3.4 gal/hour 12.9 l/hour
Power at rated PTO speed	48.49 hp 36.2 kW
Fuel use	3.0 gal/hour 11.4 l/hour
Drawbar performance
Max power	43.47 hp 32.4 kW
Fuel use	3.4 gal/hour 12.9 l/hour
Gear 3 used for power test.
Max pull	6,039 lbs 2739 kg
Gear 1 used for pull test.

Photos

1965 David Brown 990 Implematic, right side.