🏷️ Basic Information

Make:

BMW

Model:

3 Series

Chassis Code:

E21

Model Year:

1977

Generation Code:

E21

Generation Years:

1975-1983

👋 Introduction

Vehicle Segment:

Compact Executive Sedan/Coupe, a pioneering model for BMW's sports sedan image.

Key Selling Points:

Sporty handling, refined engineering, premium build quality, and a driver-focused experience.

Primary Competitors:

Mercedes-Benz W123, Alfa Romeo Alfetta, Audi 80, Ford Capri, Opel Rekord.

Manual Advantage:

Vehicle-specific, factory-level detail, replacing the need for generic information or dealer service.

Digital Format Benefits:

Portability, searchability, printable sections, and resistance to physical wear and tear.

📋 Manual Details

Vehicle Models Covered:

All 1977 BMW 3 Series (E21) models

Repair Scope:

A-Z, all repairs

Estimated Page Count:

Likely extensive, typically 500+ pages for full factory manuals of this era.

Manual Type:

Factory Service and Repair Manual

Language:

English

Digital Format:

PDF

File Compatibility:

Windows (Vista 32/64, XP, ME, 98, NT, 2000), Mac

📖 Manual Coverage

Engine Mechanical:

Complete engine overhaul, component disassembly, inspection, and reassembly for various engine variants of the E21.

Fuel System:

Carburetor service (e.g., Solex, Zenith) and injection system (e.g., Bosch K-Jetronic) diagnosis, repair, and adjustments, fuel pumps, lines, and filters.

Ignition System:

Distributor, coil, spark plugs, ignition timing, electronic ignition components diagnosis and repair.

Cooling System:

Radiator, water pump, thermostat, hoses, coolant specifications, and leak diagnosis.

Lubrication System:

Oil pump, oil pan, oil filter, oil specifications, and oil change procedures.

Emission Control:

Catalytic converter systems (if applicable for export models), air injection, exhaust gas recirculation (EGR) diagnosis and repair.

Transmission Manual:

Clutch assembly, manual gearbox overhaul, gear shifting mechanisms, fluid specifications, and repair.

Transmission Automatic:

Automatic transmission diagnosis, fluid checks, adjustments, and component repair (if equipped).

Drivetrain:

Driveshaft, universal joints, differential, axle shafts, wheel bearings, and lubrication.

Suspension:

Front and rear suspension components (struts, control arms, bushings, ball joints), alignment specifications, and shock absorber replacement.

Steering:

Steering rack/box, tie rods, steering column, steering wheel, power steering system (if equipped), and alignment.

Brakes:

Front and rear brake systems (disc/drum), brake pads/shoes, calipers/wheel cylinders, master cylinder, brake lines, fluid specifications, parking brake, and ABS (if applicable for later models).

Electrical System:

Battery, alternator, starter motor, lighting system, gauges, switches, fuses, relays, and body electrical components.

Body Exterior:

Body panel repair, doors, hood, trunk lid, windows, mirrors, bumpers, and trim.

Body Interior:

Seats, dashboard, instrument panel, carpeting, door panels, headliner, and trim.

HVAC:

Heating system, ventilation, air conditioning (if equipped), blower motor, and climate controls.

Maintenance Procedures:

Regular scheduled maintenance, fluid changes, filter replacements, tune-ups, and inspections.

Diagnostic Procedures:

Troubleshooting guides, symptom-based diagnostics, component testing, and fault code interpretation (if applicable).

Repair Procedures:

Detailed, step-by-step instructions for all mechanical, electrical, and body repairs.

Wiring Schematics:

Complete and detailed electrical wiring diagrams for all vehicle systems.

Torque Specifications:

Precise torque values for all critical fasteners during assembly and disassembly.

Special Tools:

Identification and usage instructions for specialized tools required for certain procedures.

Technical Depth:

Comprehensive, from basic maintenance to complete engine and transmission rebuilds, including diagnostics and electrical troubleshooting.

📊 Manual Specifications

File Format Type:

Adobe PDF

Searchability:

Likely text-searchable if created from a digital source, enabling quick information retrieval.

Printable Pages:

All pages are printable, allowing users to print only necessary sections.

Image Resolution:

High-quality, allowing for enlargement of diagrams and illustrations for clarity.

Binding Type:

Digital (PDF), no physical binding.

Paper Type For Printing:

User-dependent (standard paper, workshop grade paper).

⚙️ Engine Specifications

Engine Variants 1977:

Typically M10 engine variants: 316 (1.6L), 318 (1.8L), 320/4 (2.0L Inline-4). Later in E21 production, 6-cylinder engines were introduced (e.g., 320/6, 323i).

Example 320I Displacement:

1990 cc (M10B20 engine)

Example 320I Horsepower:

Approx. 109 hp (DIN) / 102 hp (SAE) depending on market and specific engine tune.

Example 320I Torque:

Approx. 160 Nm (118 lb-ft) at ~3500 rpm.

Fuel Delivery Typical:

Carburetor (e.g., Solex 32/36 or Zenith 35/40) for 316/318/320/4, Bosch K-Jetronic fuel injection for 320i.

Ignition Type:

Typically distributor-based ignition with breaker points or early electronic ignition systems.

Cooling System Type:

Water-cooled, pressurized system with a thermostat and fan.

🔧 Transmission

Standard Transmission Type:

4-speed manual transmission was common.

Optional Transmission Type:

3-speed or 4-speed automatic transmission (e.g., ZF 3HP14/3HP22) available on some models.

Clutch Type:

Single dry plate clutch.

Final Drive Type:

Rear-wheel drive with a limited-slip differential (LSD) available as an option on performance models.

📐 Dimensions

Body Styles:

2-door sedan, 2-door coupe (often referred to as 'sedan' as well for the E21 generation due to its pillarless design).

Wheelbase:

Approx. 2570 mm (101.2 in).

Length:

Approx. 4360 mm (171.7 in).

Width:

Approx. 1610 mm (63.4 in).

Height:

Approx. 1380 mm (54.3 in).

Curb Weight Range:

Approx. 1100 - 1300 kg (2425 - 2866 lbs), depending on engine and equipment.

Wheel Bolt Pattern:

4x100 mm.

Wheel Offset Et:

Typically ET18 to ET25.

🛡️ Safety Features

Crash Test Era:

Pre-modern era of standardized crash testing; relied on internal BMW safety development.

Braking System:

Front disc brakes, rear drum brakes standard on most models. Some later E21s or specific markets might have had rear discs.

Steering Assist:

Manual steering standard; power steering was an optional extra.

Seat Belts:

Lap and shoulder belts (3-point) in the front, lap belts in the rear.

Body Structure:

Designed with a strong safety cage, crumple zones, and reinforced pillars (though fewer than modern standards).

Windshield:

Laminated safety glass.

💡 Technology Features

Infotainment System:

Basic analog radio, often AM/FM stereo. Cassette player optional or dealer-installed later.

Speaker Configuration:

Typically 2 or 4 speakers.

Cruise Control:

Optional on some models, typically mechanical or vacuum-actuated.

Speed Sensitive Steering:

Not available.

Connectivity Features:

None (pre-digital era). Antennas for radio reception.

Instrument Cluster:

Analog gauges including speedometer, tachometer, fuel level, engine temperature, and oil pressure warning light. Some models had additional warning lights.

🔧 Maintenance

Oil Change Interval Typical:

Every 5,000-7,500 miles (8,000-12,000 km) or annually.

Tune Up Interval:

Spark plugs, points (if applicable), and distributor cap/rotor typically every 15,000-25,000 miles (24,000-40,000 km).

Coolant Change:

Every 2-3 years or as recommended by fluid type.

Engine Oil Specification:

API SF or SG rated oils, typically SAE 10W-40 or 20W-50 depending on climate. Consult specific manual for exact viscosity.

Coolant Specification:

Ethylene glycol based antifreeze mixed 50/50 with distilled water. Always use BMW-approved or equivalent coolant.

Manual Transmission Fluid:

GL-4 rated gear oil, e.g., SAE 75W-90 or 80W-90.

Automatic Transmission Fluid:

Dexron II or equivalent ATF.

Brake Fluid Specification:

DOT 3 or DOT 4 brake fluid.

Common E21 Issues:

Rust (especially around wheel arches, sills, and subframes), aging rubber bushings, fuel distributor issues on K-Jetronic, electrical connectors degradation, ignition system components (points, condenser, coil).

Typical Repairs:

Bushings replacement, fuel line replacement, fuel injector service, brake caliper rebuilds, radiator replacement.

📚 Vehicle History

Bmw Sporty Image:

The E21 solidified BMW's reputation for building driver-oriented cars with excellent handling and build quality, transitioning from the Neue Klasse.

E21 Introduction:

Introduced in 1975 as the successor to the BMW 02 Series, it was BMW's first compact executive car with a monocoque body and MacPherson strut front suspension.

E21 Design:

Known for its clean, simple design language, often attributed to Paul Bracq, and its distinctive 'shark nose' front.

E21 Engine Progression:

Initially launched with 4-cylinder engines, 6-cylinder engines (M20 series) were introduced in later model years (e.g., 320/6, 323i) which significantly boosted performance.

Production Period:

1975–1983

Manufacturing Locations:

Mainly Dingolfing, Germany; also assembled in other countries through CKD kits.

Total Production Units:

Approximately 724,000 units.

🏆 Awards & Recognition

E21 Reputation:

Widely recognized for its driving dynamics and contributing to BMW's 'Ultimate Driving Machine' slogan.

Automotive Press Reviews:

Consistently praised by automotive journalists for its handling, braking, and build quality, establishing BMW as a performance leader in its class.