🏷️ Basic Information

Make:

BMW

Model:

3 Series (E21)

Engine Variants Covered:

315 (M10B16), 318i (M10B18), 320i (M20B20), 323i (M20B23)

E Code:

E21

Chassis Code:

E21

👋 Introduction

Target Audience:

BMW owners seeking to perform their own maintenance and repairs, automotive technicians, classic BMW enthusiasts.

Value Proposition:

Provides factory-exact information, equivalent to dealership service manuals, enabling cost savings and accurate repairs. Offers comprehensive coverage of multiple engine variants within the E21 chassis.

Manual Advantage:

Vehicle-specific, not generic. Instant download eliminates shipping costs and waiting times. Searchable and printable pages for practical workshop use.

📋 Manual Details

Comprehensive Coverage:

Engine overhaul and rebuilding, brakes, sunroof, timing belt replacement, trouble codes, wiring diagrams, troubleshooting and diagnostics, computer diagnostic trouble tree charts, engine performance, front end and alignment procedures and specifications, suspension, transmission removal and installation, air conditioning service and capacities, transmission in-car servicing, computer diagnostic codes, firing orders, detailed specifications on every model covered, factory maintenance schedules and charts, serpentine belt routings with diagrams, timing belt service procedures, brake servicing procedures, driving concerns, complete torque specifications, U-joint and CV-joint service procedures, repair procedures, complete wiring diagrams, vacuum diagrams.

Estimated Page Count:

Likely several hundred pages, typical for a complete factory service manual.

Type:

Service and Repair Manual

Language:

English

Format:

PDF

📖 Manual Coverage

Mechanical Systems:

Engine mechanical, cooling system, fuel system, exhaust system, drivetrain, suspension, steering, brakes, chassis.

Electrical Systems:

Ignition system, starting and charging system, lighting system, instrumentation, wiring diagrams, electronic control units (ECUs) for fuel injection and ignition (where applicable).

Body And Interior:

Sunroof operation and repair, body panels, interior trim, climate control (including A/C).

Maintenance Procedures:

Scheduled maintenance, fluid changes, filter replacements, belt inspections and replacements, ignition timing adjustment, valve clearance adjustment.

Repair Procedures:

Engine rebuilds, transmission service (in-car and removal/installation), brake caliper and pad replacement, suspension component replacement, steering rack overhaul, driveshaft and U-joint service, sunroof mechanism repair.

Diagnostic Procedures:

Trouble code interpretation, diagnostic trouble tree charts, symptom-based troubleshooting, electrical system diagnostics, engine performance analysis.

Depth Of Coverage:

Factory-level detail, suitable for professional technicians and advanced DIY enthusiasts. Covers complete overhaul and rebuilding procedures.

📊 Manual Specifications

Digital Format:

PDF (Portable Document Format)

Printability:

All pages printable, allowing users to print specific sections or the entire manual. High-resolution images and diagrams.

Binding:

Not applicable (Digital PDF)

Paper Quality:

Not applicable (Digital PDF)

Required Software:

Adobe PDF Reader, WinZip (for extraction if compressed).

Zoom Functionality:

YES (Zoom in/out for detailed viewing of diagrams and text)

Download Type:

Instant Download

Operating Systems:

Compatible with all versions of Windows (including Vista 32/64, XP, ME, 98, NT, 2000) and Mac.

⚙️ Engine Specifications

Engine Types E21:

M10 (4-cylinder, carbureted and fuel-injected) and M20 (6-cylinder, fuel-injected).

Engine Performance Details:

Covers engine performance tuning, diagnostics, and repair. Specific horsepower and torque figures for 315 (M10B16), 318i (M10B18), 320i (M20B20), and 323i (M20B23) are detailed.

Fuel System Coverage:

Carburetor systems (for 315) and Bosch L-Jetronic fuel injection systems (for 'i' models). Includes fuel pump testing, injector service, and fuel pressure specifications.

Timing Belt And Chain:

Detailed procedures for timing belt replacement (for M10 engines) and timing chain maintenance/replacement (for M20 engines), including correct timing marks and tensioning.

Oil Specifications:

Covers oil capacities and recommended viscosities (e.g., SAE 20W-50, 10W-40 depending on climate) and oil filter part numbers.

🔧 Transmission

Standard Transmission:

Typically a 4-speed or 5-speed manual transmission.

Optional Transmission:

Automatic transmission (e.g., ZF 3HP18 or 3HP22) available on some models.

Transmission Service:

Covers removal and installation, clutch replacement, transmission fluid types and capacities, and in-car servicing procedures.

📐 Dimensions

Wheelbase E21:

Approx. 2,565 mm (100.9 inches) for most E21 models.

Curb Weight Range:

Varies by model and engine, typically between 1,150 kg and 1,350 kg (2,535 lbs to 2,976 lbs).

🛡️ Safety Features

Safety Ratings Era:

Reflects safety standards of the late 1970s and early 1980s. Specific crash test data from that era may be limited but structural integrity and basic safety features are covered.

Active Safety:

Disc brakes (front and rear on most models), independent front suspension, servo-assisted brakes.

Passive Safety:

Safety steering column, padded dashboard, three-point seat belts (standard on front seats).

💡 Technology Features

Infotainment Systems E21:

Basic AM/FM radio with optional cassette player. Manual covers radio removal/installation and speaker wiring.

Driver Assistance Features:

No advanced electronic driver assistance systems typical of modern vehicles. Focus is on mechanical and electrical systems.

Connectivity Features:

None.

🔧 Maintenance

Typical Oil Change Interval:

Approximately 5,000 - 7,500 miles (8,000 - 12,000 km) or 6-12 months, depending on driving conditions. Manual provides detailed factory recommendations.

Coolant Type:

Ethylene glycol-based coolant, typically a 50/50 mix with distilled water. Specific BMW coolant part numbers may be listed.

Brake Fluid Type:

DOT 3 or DOT 4 brake fluid.

Transmission Fluid Type:

Depends on transmission type (manual or automatic). Manual transmissions typically use GL-4 gear oil. Automatics use specific ATF fluids (e.g., Dexron II).

Common E21 Issues:

Rust (especially around wheel wells, rocker panels, and sunroof), aging rubber components (bushings, hoses), fuel distributor issues on early injected models, headlight switch failure, vacuum leaks.

Tune Up Specifications:

Includes spark plug gap settings, ignition timing (base and advance), idle speed adjustments, and fuel mixture adjustments (where applicable).

📚 Vehicle History

Bmw Sporting Sedan:

The E21 continued BMW's tradition of producing sporty and driver-focused sedans, building on the success of the preceding 02 series.

E21 Introduction:

Introduced in 1975 as the successor to the BMW 2002. The E21 was BMW's first compact executive car to be officially marketed as the 3 Series. Introduced the iconic shark-nose design.

Production Years E21:

1975-1983

Manufacturing Locations:

Primary production in Munich, Germany, with potential assembly in other BMW plants worldwide.

🏆 Awards & Recognition

Automotive Press Reviews:

The E21 was generally praised for its driving dynamics, responsive handling, and build quality, earning positive reviews from automotive journalists of its time for its sporting character.