🏷️ Basic Information Identification Make: David Brown Model: AD4-25 Model Variant: CAD4-30 Product Type: Factory Service Repair Manual 👋 Introduction Market Position Vehicle Segment: Agricultural Tractor (Engine Focus) Competitive Analysis Manual Advantage: Offers definitive factory-level repair and maintenance information, crucial for the longevity and performance of David Brown engines. Key Features Completeness: Official factory documentation ensures accuracy and completeness for all repair and maintenance tasks. Usability: PDF format allows for targeted printing of specific sections or the entire manual, with searchable text for quick information retrieval. 📋 Manual Details Coverage Areas Primary Focus: Engine Service and Repair Page Count Estimated Pages: Hundreds Manual Type Type: Service and Repair Manual Language Language: English Format Format: PDF Download 📖 Manual Coverage Systems Covered Engine Mechanical: Full overhaul, disassembly, assembly, inspection, and repair of all internal engine components (pistons, rings, connecting rods, crankshaft, camshaft, valves, timing gears). Engine Fuel System: Carburetor adjustment, overhaul, and troubleshooting; fuel pump operation and service; fuel filter replacement. Engine Ignition System: Spark plug specifications, ignition timing, coil and distributor testing. Engine Cooling System: Radiator, water pump, thermostat, and coolant hose service and replacement. Engine Lubrication System: Oil pump operation, oil filter service, oil pressure checks, and lubrication diagrams. Engine Exhaust System: Muffler, exhaust pipe, and manifold inspection and replacement. Procedures Included Preventive Maintenance: Recommended service intervals, oil change procedures, filter replacement, and general inspection points. Troubleshooting: Systematic diagnostic guides for common engine problems, including misfires, starting issues, power loss, and overheating. Repair Procedures: Step-by-step instructions for component removal, installation, and repair for all major engine systems. Specifications: Detailed torque specifications, clearances, tolerances, and measurements for engine components. Technical Depth Depth: Comprehensive, covering everything from basic fluid checks to complete engine rebuilds and advanced diagnostics. 📊 Manual Specifications File Format File Type: PDF Print Quality Resolution: High-resolution, suitable for clear printing of diagrams and text. Binding Type Binding: N/A (Digital Download) Paper Type Paper Recommendation: Standard paper for printing; glossy paper recommended for diagrams. ⚙️ Engine Specifications Primary Engine Engine Model: AD4 series Engine Type: Diesel, 4-cylinder Bore: 94.0 mm (3.70 in) Stroke: 110.0 mm (4.33 in) Displacement: 3.0 Liters (182.8 cu in) Compression Ratio: Approx. 17.5:1 (verify with specific engine variant) Performance Horsepower Ad4 25: Approx. 25 HP (at rated RPM) Horsepower Cad4 30: Approx. 30 HP (at rated RPM) Fuel System Fuel Type: Diesel Injection System: Direct Injection (typically via Lucas CAV or similar) Governor: Mechanical (variable speed control) 🔧 Transmission Standard Type: Manual Gearbox (specific configurations vary by tractor model) Optional Features: PTO (Power Take-Off), Hi-Lo gear splitter (depending on tractor model) Features Fluid Type: Tractor Hydraulic Fluid / Universal Tractor Transmission Oil (UTTO) - Specific grade to be confirmed in manual 📐 Dimensions Exterior Note: Engine dimensions are internal to the tractor chassis and vary significantly by tractor model. Manual focuses on engine internal specifications. 🛡️ Safety Features Ratings Note: Safety ratings are typically applied to the complete tractor, not just the engine. Manual may cover safe operating procedures related to the engine. Active Features Engine Safety: Engine safety cut-offs, temperature monitoring (if equipped). Passive Features Engine Shielding: Heat shields, guards for moving parts (belts, fans). 💡 Technology Features Infotainment Note: N/A for this era of agricultural machinery; focus is on mechanical functionality. Driver Assistance Note: N/A for this era of agricultural machinery; focus is on mechanical functionality. Connectivity Note: N/A for this era of agricultural machinery; focus is on mechanical functionality. 🔧 Maintenance Service Intervals Oil Change Interval: Typically 100-250 hours, depending on operating conditions and oil type (refer to manual for specific recommendations). Air Filter Cleaning: Regular inspection and cleaning/replacement based on dust levels and operating hours. Fuel Filter Replacement: As per manual recommendations, often tied to hours or as needed for fuel quality. Fluid Specifications Engine Oil Type: API CD or CE rated diesel engine oil, SAE 10W-30 or 15W-40 depending on climate (verify in manual). Engine Oil Capacity: Approx. 6.0 Liters (6.3 US Quarts) - including filter (verify in manual). Coolant Type: Ethylene Glycol based antifreeze mixture (typically 50/50 with distilled water). Known Issues Common Wear Items: Valve seats, piston rings, injector tips, water pump seals. Typical Failures: Overheating due to cooling system neglect, fuel system contamination, worn injection pump timing. Troubleshooting Tips Starting Problems: Check battery, glow plugs, fuel delivery, and injection timing. Power Loss: Inspect air filter, fuel filters, exhaust restriction, and valve clearances. 📚 Vehicle History Brand Heritage Manufacturer: David Brown Tractors Ltd. Origin Country: United Kingdom Model Evolution Engine Introduction: The AD4 engine series was a workhorse for David Brown in the mid-to-late 20th century, powering many of their popular tractor models. Variants: AD4-25, AD4-30, and other variations based on tuning and application. Production Production Period: Mid-1960s to late 1970s (approximate for engine variants within tractor lines) 🏆 Awards & Recognition Recognitions Note: Tractor models equipped with...