🏷️ Basic Information Identification Make: BMW Model: 3-series Chassis Code: E21 Year: 1975 Generation Generation Code: E21 (First Generation) Codes Vin Code: 4th digit (engine type), 5th digit (model series) 👋 Introduction Market Position Target Audience: BMW owners, independent repair shops, automotive enthusiasts seeking detailed information Competitive Analysis Value Proposition: Vehicle-specific, factory-level repair data, replacing generic information for accurate and efficient repairs. Key Features Convenience: Single PDF manual, easy navigation, selective printing, protection against physical wear and tear Accuracy: Exact same information used by dealership technicians 📋 Manual Details Coverage Areas Coverage Summary: All models and all repairs A-Z for the 1975 BMW 3-series (E21) Page Count Estimated Page Count: Highly Detailed (likely several hundred pages based on scope) Manual Type Type: Service and Repair Manual Language Language: English Format Digital Format: PDF 📖 Manual Coverage Systems Covered Engine Mechanical: Complete engine overhaul, disassembly, assembly, component specifications Engine Control System: Ignition timing, carburetor adjustment, fuel injection systems (if applicable to 1975 models) Fuel System: Fuel tank, fuel pump, fuel lines, carburetor service and specifications Emission Control: Emissions system components, diagnosis, and adjustments Cooling System: Radiator, water pump, thermostat, cooling fan, coolant specifications Lubrication System: Oil pump, oil filter, oil pan, lubrication specifications, oil change intervals Ignition Starting Charging: Battery, alternator, starter motor, ignition coil, spark plugs, distributor, ignition system troubleshooting Automatic Transmission: Automatic transmission service, fluid types, troubleshooting, repair procedures Manual Transmission: Manual transmission service, clutch operation, lubrication, repair procedures Drivetrain: Transfer case (if applicable), propeller shaft, drive shafts, universal joints, differential service and specifications Suspension: Front and rear suspension components, alignment specifications, shock absorbers, bushings Wheels Tires: Wheel bolt patterns, tire pressure specifications, wheel bearing service Brake Control System: Brake fluid specifications, bleeding procedures, master cylinder, brake booster Brakes: Front and rear brake systems (disc/drum), caliper/wheel cylinder service, brake pad/shoe replacement, rotor/drum specifications Parking Brake: Parking brake mechanism, adjustment, and service Steering Column: Steering column assembly, ignition switch, steering lock Power Steering: Power steering system components, fluid, troubleshooting (if equipped) Air Conditioning: A/C system components, refrigerant types, service, and troubleshooting (if equipped) Supplemental Restraint System: Airbag system components, diagnosis, and safety precautions (though less prevalent on 1975 models, coverage may exist for early systems or warnings) Seat Belts: Seat belt operation, adjustment, and replacement Engine Immobilizer: Engine immobilizer system (may not be applicable to 1975 models, but included in description) Cruise Control: Cruise control system operation, adjustment, and troubleshooting (if equipped) Wiper Washer: Wiper motor, linkage, washer pump, fluid reservoir, blade replacement Door Locks: Door lock mechanisms, actuators, key cylinders, central locking (if applicable) Meter Audio Visual: Instrument cluster, gauges, tachometer, speedometer, radio (if equipped), speaker system Horn: Horn operation, wiring, replacement Windshield Glass Mirror: Windshield replacement, sealants, mirror adjustment and replacement Instrument Panel: Instrument panel removal, installation, and illumination Seats: Seat adjustment mechanisms, upholstery, seat belt anchor points Engine Hood Door: Hood and door hinges, latches, alignment, weatherstripping Exterior Interior: Body panels, trim, bumpers, interior trim panels, headliner, carpet Electrical System: Comprehensive wiring diagrams, fuse box layout, lighting systems, accessory circuits Multiplex Can Communication: Multiplex systems and CAN communication (less likely to be extensive for a 1975 model, but listed in description) Procedures Included Maintenance: Scheduled maintenance, fluid changes, filter replacements, inspections Diagnostics: Troubleshooting common problems, diagnostic flowcharts, symptom-based troubleshooting Repair: Step-by-step repair instructions for all covered systems, component replacement, adjustments Overhaul: Complete engine and transmission overhaul procedures Rebuilding: Rebuilding of major components like carburetors, brake calipers, starter motors Installation: Installation of replacement parts and accessories Alignment: Wheel alignment procedures and specifications Technical Depth Depth Of Information: Factory-level detail, suitable for professional technicians and advanced DIY enthusiasts Diagrams Illustrations: Extensive use of diagrams, illustrations, and photographs for clarity Wiring Schematics: Complete and detailed wiring schematics for all electrical systems Specifications: Detailed technical specifications for all components and systems 📊 Manual Specifications File Format Compatibility: Windows Vista (32/64), XP, ME, 98, NT, 2000, and Mac compatible Requirements: Adobe PDF Reader and Winzip (free online) Print Quality Printability: All pages are printable; option to blow up images and print enlarged copies Binding Type Binding: Digital PDF (no physical binding) Paper Type Paper Type: N/A (Digital) ⚙️ Engine Specifications Primary Engine Engine Families: M10 (4-cylinder inline) Performance Typical Displacement: 1.8L (M10B18), 2.0L (M10B20), 2.3L (M10B23 - Alpina) Horsepower Range: Approximately 90-125 hp depending on engine variant Torque Range: Approximately 105-135 lb-ft depending on engine variant Fuel System Carburetion: Solex, Zenith, or Pierburg carburetors (single or twin-choke configurations) Fuel Type: Unleaded gasoline (as regulations shifted) 🔧 Transmission Standard Standard Transmission: 4-speed manual gearbox Optional Optional Transmission: 3-speed ZF automatic transmission Features Clutch Type: Single dry plate, diaphragm spring clutch 📐 Dimensions Exterior Body Styles: 2-door sedan, 4-door sedan Wheelbase: Approx. 97.2 inches (2469 mm) Length: Approx. 165.7 - 168.5 inches (4209 - 4280 mm) depending on variant Width: Approx. 64.8 inches (1646...