🏷️ Basic Information Identification Make: BMW Model: 3 Series Chassis Code: E21 Product Name: BMW 3 Series E21 1975-1983 Service Repair Manual Generation Generation Code: E21 Codes Engine Codes Covered: M10 family (e.g., M10B18, M10B20, M10B23) 👋 Introduction Market Position Historical Context: The E21 was BMW's first foray into the compact executive sedan segment, establishing the iconic 3 Series lineage. It replaced the aging Neue Klasse and set the standard for sporty handling and build quality in its class. Competitive Analysis Competitors: Primarily competed with cars like the Mercedes-Benz W201 (later known as the 190E), Audi 80, Alfa Romeo Alfetta, and Opel Rekord. Key Features Design Philosophy: Characterized by BMW's signature Hofmeister kink in the rear window, a driver-focused cockpit, and robust mechanical engineering. Known for its excellent weight distribution and engaging driving dynamics. Manual Benefit: Enables owners and technicians to perform a wide range of repairs and maintenance, reducing labor costs and ensuring proper upkeep of this classic BMW. Manual Benefit Value Proposition: An indispensable tool for preserving the performance and longevity of the BMW E21. Provides the same level of detail found in official BMW service documentation. 📋 Manual Details Coverage Areas Vehicle Model Years Covered: 1975, 1976, 1977, 1978, 1979, 1980, 1981, 1982, 1983 Engine Variants Covered: All E21 3 Series engine variants, primarily 4-cylinder M10 engines Market Regions Covered: Global (comprehensive, as per BMW's standard) - implicitly covers US, European, and other markets where E21 was sold. Page Count Estimated Page Count: Estimated 1000+ pages (typical for comprehensive service manuals of this era and scope) Manual Type Type: Service and Repair Manual Language Language: English Format Format: PDF (Downloadable) 📖 Manual Coverage Systems Covered Powertrain: Engine mechanical (including complete disassembly and reassembly), fuel system, ignition system, cooling system, exhaust system, lubrication system, engine control system. Drivetrain: Manual transmission, automatic transmission, clutch, drive shafts, universal joints, differential, rear axle, front suspension, rear suspension, steering system (including power steering). Brakes: Hydraulic brake system (front discs, rear drums or discs depending on model), parking brake system, brake control systems. Electrical: Complete electrical system, including starting system, charging system (alternator, regulator), lighting, ignition system, instrumentation, diagnostics, wiring diagrams, fuses, relays, battery. Chassis And Body: Body panels, doors, hood, trunk lid, glass, mirrors, interior trim, seats, seat belts, HVAC (heating, ventilation, and air conditioning), windshield wipers and washers, door locks, instrument panel. Emission Control: Emission control systems and specifications relevant to the model years covered. Procedures Included Maintenance: Regular maintenance, tune-ups, fluid changes, filter replacements, inspections, lubrication. Diagnostics: Troubleshooting procedures for common and uncommon issues, diagnostic charts, symptom-based troubleshooting, electrical system diagnostics. Repair: Step-by-step repair instructions for all major mechanical, electrical, and body components, including complete engine rebuilds, transmission overhauls, suspension component replacement, brake system repairs. Overhaul: Detailed procedures for complete disassembly and reassembly of major components like engines and transmissions. Adjustments: Procedures for adjusting carburetors, ignition timing, valve clearances, clutch linkage, etc. Technical Depth Depth: Comprehensive. Covers everything from basic fluid checks to full engine and transmission rebuilds, including detailed technical specifications and tolerances. Target Audience: Professional mechanics and experienced DIY enthusiasts. 📊 Manual Specifications File Format Format: PDF Compatibility: All PC based Windows operating systems, Mac, Linux Print Quality Printability: Fully printable, allowing users to print specific sections or the entire manual. Resolution: High resolution, ensuring clarity of text, diagrams, and photographs. Binding Type Binding: N/A (Digital PDF format, not a physical book) Paper Type Paper Type: N/A (Digital PDF format, not a physical book) Software Requirements Required Software: WinZip (or similar unzipping utility) and Adobe PDF Reader (or compatible PDF viewer). ⚙️ Engine Specifications Primary Engine Engine Family: M10 Engine Configurations: Inline-4 cylinder (SOHC) Performance Horsepower Range: Approximately 75 hp to 125 hp, depending on specific engine variant (e.g., 316, 318, 320i, 323i). Torque Range: Approximately 105 Nm to 180 Nm, depending on specific engine variant. Fuel System Fuel Delivery: Carbureted (e.g., Solex, Zenith) or Bosch K-Jetronic fuel injection (for 'i' models). Fuel Type: Unleaded gasoline (as emissions regulations evolved) Cooling System Cooling Type: Liquid-cooled Lubrication Oil Type Recommendation: Refer to manual for specific oil viscosity (e.g., 20W-50, 15W-40, 10W-40 depending on climate and engine condition). Modern equivalents like 5W-30 or 10W-40 are often suitable with correct API rating. Engine Mechanical Bore Stroke: Varies by engine (e.g., 320i: 80.0 mm x 99.0 mm) 🔧 Transmission Standard Type: 4-speed manual transmission (standard on most models). Optional Type: 3-speed ZF automatic transmission (optional on most models). Features Clutch Type: Single dry plate, hydraulically operated. Fluid Specifications Manual Transmission Fluid: API GL-4 or GL-5, SAE 75W-90 or 80W-90 gear oil. Automatic Transmission Fluid: Dexron-III or equivalent (GM specification). 📐 Dimensions Exterior Length: Approx. 4360 mm (171.7 in) Width: Approx. 1610 mm (63.4 in) Height: Approx. 1380 mm (54.3 in) Weights Curb Weight: Approx. 1150 - 1300 kg (2535 - 2866 lbs),...