Market Position:
The David Brown 780 was a versatile and popular utility tractor during its production run, serving agricultural and industrial needs. This parts catalog is crucial for owners and mechanics maintaining these robust machines.
Target Audience:
Farm owners, tractor mechanics, agricultural repair shops, parts suppliers, and historical vehicle enthusiasts.
Competitive Landscape:
Competed with similar models from manufacturers like Fordson, Massey Ferguson, and International Harvester in the mid-horsepower utility tractor segment.
Key Features:
The 780 model was known for its robust construction, reliable diesel engine, and adaptable PTO and hydraulic systems, making it suitable for a wide range of farm operations.
Covered Systems:
Engine, transmission, drivetrain, hydraulics, steering, braking system, electrical system, chassis, front axle, rear axle, PTO, linkage, operator controls, operator station, bodywork, implements mounting points.
Engine Components:
Cylinder head, block, pistons, crankshaft, camshaft, valves, oil pump, water pump, fuel system components (injectors, pumps), exhaust system parts.
Transmission Components:
Gears, shafts, bearings, synchronizers, clutch assembly, PTO gearbox, differential assembly.
Hydraulic System Components:
Hydraulic pump, control valve, lift arms, draft control components, hydraulic cylinders, fluid reservoir, filter elements.
Steering System Components:
Steering column, steering box, tie rods, king pins, front axle components.
Braking System Components:
Brake discs or drums, calipers or shoes, master cylinder, brake pedal linkage, hydraulic lines.
Electrical System Components:
Starter motor, alternator, battery, wiring harnesses, lighting components (headlights, taillights), switches, instrumentation (fuel gauge, temperature gauge).
Chassis And Bodywork Components:
Frame components, drawbar, fenders, operator platform, seat mounting, radiator grille, fuel tank, battery box.
Included Procedures:
Parts identification, assembly diagrams, sub-assembly breakdowns, component listing with part numbers, exploded views for visual reference.
Assembly Diagrams:
Detailed diagrams showing the correct assembly order and relationships of components for various systems.
Part Number Identification:
Explicit listing of original equipment manufacturer (OEM) part numbers for every component illustrated.
Technical Depth:
Detailed parts breakdown for repair, replacement, and inventory management. Essential for accurate parts ordering and understanding component relationships.
Precision Level:
High precision in component identification and referencing, essential for ordering correct replacement parts.
Usage Context:
Primarily for parts ordering, inventory management, and understanding the construction of the tractor. Not a diagnostic or repair manual in terms of step-by-step procedures, but critical for acquiring the necessary parts for those procedures.
Engine Model:
Likely a David Brown diesel engine (specific model designation varies by variant, e.g., AD4/380, AD4/400).
Displacement:
Typically in the range of 3.5 to 4.0 liters, depending on the specific engine variant.
Horsepower Range:
Around 50-60 PTO horsepower (estimated).
Torque Output:
Estimated torque figures would be available in specific engine variant documentation, but would support heavy draft work.
Injection System:
Likely direct injection, potentially with rotary or inline fuel pumps from manufacturers like CAV or Simms.
Wheelbase:
Varies by specific 780 model variant (e.g., standard, narrow, low clearance).
Overall Length:
Approximately 10-12 feet (3-3.6 meters) depending on hitch configuration.
Overall Width:
Around 5-6 feet (1.5-1.8 meters) depending on tire size and axle width.
Operating Weight:
Approximately 4,000 - 4,500 lbs (1800 - 2000 kg) depending on configuration.
Tire Sizes:
Commonly fitted with rear tires around 13.6-28 or 14.9-28 and front tires around 6.00-16 or 7.50-16.
Safety Considerations:
As a tractor of its era, safety features are basic. Emphasis is on operator responsibility and proper use of the machine. The catalog would identify safety-related parts like brake components, steering linkages, and guards.
Active Safety Components:
Brake system components, steering system components, lighting and signaling parts.
Passive Safety Components:
Guards for PTO shafts and moving parts, operator platform structure, fenders.
Typical Engine Oil Change Interval:
Often around 100-250 operating hours, depending on operating conditions and oil type used.
Typical Hydraulic Oil Change Interval:
Typically every 500-1000 operating hours.
Engine Oil Specification:
SAE 10W/30 or 15W/40 diesel engine oil (API CD or CCMC D2/D3 classification recommended).
Hydraulic Oil Specification:
TO-2 or equivalent multi-purpose tractor hydraulic fluid (e.g., 10W-30 or 20W-30 tractor oil).
Transmission Fluid Specification:
Likely same as hydraulic oil specification (TO-2 or equivalent).
Gearbox Oil Specification:
Likely shared with transmission and hydraulics; check manual for specific GL specifications if separate.
Engine Coolant Type:
Ethylene glycol based antifreeze/coolant, typically a 50/50 mix with water.
Common Wear Items:
Clutch components, brake linings, hydraulic pump seals, engine valve guides, starter motor, electrical wiring degradation.
Potential Issues:
Hydraulic system leaks, minor electrical faults, starter motor issues, potential for rust on bodywork due to age and exposure.
Common Maintenance Tasks:
Regular engine oil and filter changes, hydraulic fluid and filter changes, checking and topping up coolant, greasing pivot points, checking tire pressures, inspecting brake function.
Filter Part Numbers:
Specific part numbers for engine oil filters, fuel filters, and hydraulic filters would be detailed within the catalog.
Brand Heritage:
David Brown Tractors, a British manufacturer, has a long history of producing robust and reliable agricultural machinery, known for their distinctive red paint schemes.
Model Evolution:
The 780 was part of David Brown's product line in the 1960s and early 1970s, evolving from earlier models and paving the way for later Case-David Brown integrated designs after the acquisition.
Production Period:
Likely produced from the mid-1960s through the early-to-mid 1970s.
Manufacturing Location:
United Kingdom (historically, Meltham, Yorkshire).
