🏷️ Basic Information Identification Make: BMW Model: 3 Series Generation: E21 Production Years: 1975-1983 Codes Chassis Code: E21 👋 Introduction Market Position Positioning: The BMW E21 established the modern compact executive sedan segment, offering a balance of sporty driving dynamics and premium build quality. Competitive Analysis Competitors: Mercedes-Benz W123, Audi 80/Fox, Alfa Romeo Alfetta, Volvo 240 Series Key Features Driving Dynamics: Rear-wheel drive, independent suspension, near-perfect weight distribution, driver-focused cockpit. Design: Iconic Hofmeister kink, upright kidney grille, clean lines, excellent visibility. 📋 Manual Details Coverage Areas Primary Coverage: Mechanical, Electrical, Bodywork, Maintenance, Repair Engine Coverage: M10, M20 (4-cylinder and 6-cylinder variants) Transmission Coverage: 4-speed Manual, 5-speed Manual (Getrag 245), 3-speed Automatic (ZF 3HP18, ZF 3HP22) Page Count Estimated Pages: 500-1000+ Manual Type Type: Comprehensive Service and Repair Manual Language Language: English (assumed, based on typical manual offerings for this model) Format Format: Digital (PDF) 📖 Manual Coverage Systems Covered Engine Mechanical: Engine overhaul, cylinder head, pistons, crankshaft, camshaft, timing, lubrication system Fuel System: Carburetor (Zenith, Solex, Weber), Fuel injection (Bosch L-Jetronic, K-Jetronic) Ignition System: Distributor, ignition coil, spark plugs, timing adjustment Cooling System: Radiator, water pump, thermostat, hoses, fan Exhaust System: Manifold, catalytic converter (later models), muffler, pipes Transmission Mechanical: Clutch, gearbox overhaul, gear selection mechanism Drivetrain: Driveshafts, universal joints, differential Suspension: Front struts, rear trailing arms, springs, shock absorbers, bushings Steering: Steering rack, tie rods, steering column Brakes: Front discs, rear drums, master cylinder, brake lines, parking brake Electrical System: Wiring diagrams, battery, alternator, starter, lighting, gauges, fuses, relays Body And Chassis: Body panel removal, door mechanisms, interior trim, glass, rust repair Heating And Ventilation: Blower motor, heater core, ventilation controls Procedures Included Maintenance: Oil changes, filter replacements, spark plug replacement, coolant flush, belt adjustments Troubleshooting: Diagnostic procedures for common faults, symptom-based troubleshooting guides Repair: Component replacement, major overhaul procedures, specific repair instructions Assembly Disassembly: Detailed steps for dismantling and reassembling all major vehicle systems Diagnostics: Electrical system testing, fuel system pressure testing, engine compression testing Painting: Surface preparation, paint application guidelines, touch-up procedures Technical Depth Depth: Comprehensive, covering basic maintenance to full engine and transmission rebuilds Detail Level: Detailed step-by-step instructions with torque specifications and diagrams 📊 Manual Specifications File Format Format: PDF (Portable Document Format) Searchable: Yes (typically, for well-produced digital manuals) Print Quality Printability: Printable by section or in full Binding Type Binding: N/A (Digital Format) Paper Type Paper Type: N/A (Digital Format) ⚙️ Engine Specifications Primary Engine Engine Code 1: M10 (M10B18, M10B20) Engine Code 2: M20 (M20B20, M20B23) Performance 1 Displacement 1: 1.8L (1766cc) and 2.0L (1990cc) for M10 Horsepower 1: 90-105 hp for M10 variants Torque 1: 140-170 Nm for M10 variants Performance 2 Displacement 2: 2.0L (1990cc) and 2.3L (2316cc) for M20 Horsepower 2: 105-143 hp for M20 variants Torque 2: 165-205 Nm for M20 variants Fuel System Fuel Delivery: Carbureted (e.g., Zenith 35/40 INAT, Solex 40 ADDHE) or Bosch K-Jetronic fuel injection Engine Design Configuration: Inline-4 (M10), Inline-6 (M20) Block Material: Cast Iron Head Material: Aluminum Alloy 🔧 Transmission Standard Transmission Type: 4-speed Manual Optional Transmission Type Optional: 5-speed Manual (Getrag 245), 3-speed Automatic (ZF 3HP18/3HP22) Features Gear Ratios 5Spd: Specific ratios vary by model, but typical 5-speed ratios are available in the manual. Clutch Type: Single dry plate, hydraulically actuated 📐 Dimensions Exterior Length: Approx. 4360 mm (171.7 in) Width: Approx. 1625 mm (64.0 in) Height: Approx. 1380 mm (54.3 in) Wheelbase: Approx. 2563 mm (100.9 in) Weights Curb Weight: Approx. 1100-1250 kg (2425-2755 lbs), depending on engine and equipment Gross Vehicle Weight: Varies by model, typically around 1600-1700 kg 🛡️ Safety Features Ratings Crash Test Data: Limited official crash test data available for this era, but known for robust chassis construction. Active Features Active Safety: Four-wheel disc brakes (later models, common on 6-cyl), power-assisted brakes (optional) Passive Features Passive Safety: Crumple zones, reinforced passenger cell, padded dashboard and steering wheel, seat belts. 💡 Technology Features Infotainment Infotainment System: Basic analog radio, cassette player (optional). No digital infotainment. Driver Assistance Driver Assistance Features: None by modern standards; focus is on mechanical feedback and driver control. 🔧 Maintenance Service Intervals Oil Change Interval: Typically every 5,000-10,000 km (3,000-6,000 miles) or 6-12 months, depending on driving conditions and oil type. Timing Belt Chain: M10 and M20 engines use timing chains, generally requiring inspection rather than scheduled replacement, though tensioners and guides may need attention. Coolant Flush: Every 2-3 years or 30,000-40,000 km. Fluid Specifications Engine Oil: API SG/SH or higher, SAE 20W-50 or 10W-40 (check specific model/year for recommendations). Coolant: Ethylene glycol-based antifreeze, typically a 50/50 mix with distilled water. Brake Fluid: DOT 3 or DOT 4 (check manual for exact specification). Transmission Fluid Manual: API GL-4, SAE 75W-90 or 80W-90 gear oil. Transmission Fluid Automatic: Dexron II or equivalent. Differential Fluid: API GL-5, SAE 80W-90 gear oil. Known Issues Rust Prone...