🏷️ Basic Information

Make:

BMW

Model:

733i / 735i

Market:

U.S. Domestic Market (USDM)

Chassis Code 733I:

E23

Chassis Code 735I:

E23

Engine Code 733I:

M30B32

Engine Code 735I:

M30B34

👋 Introduction

Positioning:

Flagship luxury sedan from BMW, competing with Mercedes-Benz S-Class and other high-end executive cars of its era.

Competitors Era:

Mercedes-Benz W126 S-Class, Audi V8 Quattro, Jaguar XJ-S.

Luxuries:

Advanced engineering, superior driving dynamics for its class, plush interiors, available advanced features like climate control and electric seating.

Engine Philosophy:

Smooth, powerful inline-six engines known for their durability and performance characteristics.

📋 Manual Details

Manual Type:

Complete Official Service and Repair Manual

Language:

English

Format:

PDF

Coverage Scope:

All models and all engines for U.S. market

Estimated Page Count:

Over 1500 pages (estimated based on typical official BMW E23 manuals)

📖 Manual Coverage

Engine:

Detailed diagnosis, repair, overhaul, and tuning for M30B32 and M30B34 inline-six engines.

Fuel System:

Bosch L-Jetronic / Motronic fuel injection system diagnosis, component testing, and repair.

Ignition System:

Ignition timing, coil testing, spark plug specifications, and electronic ignition module diagnosis.

Transmission Manual:

Repair and maintenance for Getrag 5-speed manual transmissions.

Transmission Automatic:

Diagnosis and repair for ZF 4HP22 automatic transmissions, including valve body service and fluid flush procedures.

Drivetrain:

Driveshaft, differential, and axle shaft inspection and service.

Suspension:

Front and rear suspension component replacement (struts, control arms, bushings), alignment specifications, and self-leveling rear suspension (optional).

Steering:

Power steering system diagnosis, pump and rack repair, and steering linkage components.

Brakes:

Front and rear disc brake systems, ABS (Anti-lock Braking System) diagnosis and component replacement, brake fluid specifications.

Electrical System:

Complete wiring diagrams, fuse box layouts, component testing, starter, alternator, and battery service.

Climate Control:

HVAC system diagnosis, refrigerant handling, blower motor, heater core, and A/C compressor service.

Body And Trim:

Interior and exterior trim removal and installation, door mechanisms, hood and trunk latches, and glass replacement.

Chassis:

Body structural information, corrosion protection, and underbody components.

Maintenance:

Scheduled maintenance, oil changes, filter replacements, fluid checks, tune-ups.

Troubleshooting:

Systematic diagnostic procedures for common and uncommon drivability issues, electrical faults, and mechanical problems.

Repair:

Step-by-step instructions for component removal, installation, and adjustment for all major vehicle systems.

Rebuild:

Complete engine and transmission rebuild procedures, including torque specifications, clearances, and assembly sequences.

Diagnostics:

Detailed troubleshooting charts and flowcharts for identifying the root cause of malfunctions.

Torque Specifications:

Comprehensive list of all critical torque specifications for fasteners across all major systems.

Depth Level:

Comprehensive (factory-level detail)

Documentation Type:

Official Factory Service Manual

📊 Manual Specifications

File Type:

PDF

Searchability:

Likely text-searchable (depending on source scan quality)

Printability:

Printable (designed for professional use, so high resolution expected)

Binding Description:

N/A (Digital PDF format)

Paper Description:

N/A (Digital PDF format)

⚙️ Engine Specifications

Engine Type:

Inline 6-cylinder, SOHC

Displacement:

3.2 Liters (3210 cc)

Bore X Stroke:

89.0 mm x 86.0 mm

Compression Ratio:

8.0:1 (typical)

Fuel Delivery:

Bosch L-Jetronic fuel injection

Horsepower Net 733I:

Approx. 197 hp @ 5500 rpm (US spec)

Torque Net 733I:

Approx. 210 lb-ft @ 3500 rpm (US spec)

Engine Type:

Inline 6-cylinder, SOHC

Displacement:

3.4 Liters (3430 cc)

Bore X Stroke:

92.0 mm x 86.0 mm

Compression Ratio:

8.0:1 or 8.8:1 (depending on year/spec)

Fuel Delivery:

Bosch Motronic (LE-Jetronic/Motional Electronic Ignition)

Horsepower Net 735I:

Approx. 210-218 hp @ 5500 rpm (US spec, varies by year)

Torque Net 735I:

Approx. 224-230 lb-ft @ 3500 rpm (US spec, varies by year)

Fuel Type:

Unleaded Gasoline

Fuel Octane Rating:

Premium (91+ AKI recommended)

🔧 Transmission

Transmission Type Standard 733I:

4-speed automatic (ZF 4HP22)

Transmission Type Standard 735I:

4-speed automatic (ZF 4HP22)

Transmission Type Optional:

5-speed manual (Getrag 265)

Transmission Fluid Type:

ATF Dexron III (or equivalent specification, consult manual for exact BMW part number)

Automatic Transmission Modes:

Standard, Economy (S/E switch)

📐 Dimensions

Length:

Approx. 5024 mm (197.8 in)

Width:

Approx. 1798 mm (70.8 in)

Height:

Approx. 1400 mm (55.1 in)

Wheelbase:

Approx. 2830 mm (111.4 in)

Curb Weight:

Approx. 1700-1800 kg (3748-3968 lbs) depending on equipment

Gross Vehicle Weight Rating:

Approx. 2200 kg (4850 lbs)

Trunk Volume:

Approx. 500 Liters (17.7 cu ft)

🛡️ Safety Features

Crash Test Data Availability:

Limited specific data for this era, but designed to meet US safety standards of the time.

ABS:

Standard on most models, especially later E23 iterations.

Traction Control:

Rarely available, if at all, on these specific models. Primarily ABS.

Airbags:

Driver's airbag standard from mid-production, passenger airbag optional/later addition.

Seatbelts:

3-point inertia-reel seatbelts front and rear, often with pre-tensioners.

Headlights:

Halogen headlights, often with integrated fog lamps in front valance.

💡 Technology Features

Audio System:

Original BMW Bavaria C or similar premium cassette player/radio. Often paired with quality speaker systems.

Climate Control:

Automatic climate control (optional on some models, standard on higher trims) with digital displays and sensor inputs.

Cruise Control:

Standard on most models.

Power Features:

Power windows, power door locks, power seats (often with memory), power mirrors, power sunroof.

Connectivity Options:

Limited by era; primarily analog systems. Optional on-board computer (check manual for details) and early diagnostics.

🔧 Maintenance

Oil Change Interval:

Typically every 5,000 - 7,500 miles or 6-12 months, depending on driving conditions. Consult manual for specific recommendation based on oil type used.

Spark Plug Replacement:

Intervals vary (e.g., 20,000-30,000 miles for standard plugs, potentially longer for platinum). Manual will specify.

Coolant Flush:

Typically every 2-3 years or 30,000 miles. Manual will specify coolant type.

Timing Belt Chain:

M30 engines utilize a timing chain, which is designed to last the life of the engine but may require tensioner replacement over time. Manual will detail inspection points.

Engine Oil Type:

SAE 15W-40 or 10W-40, API SG or higher. Consult manual for exact BMW specification (e.g., BMW High Performance SAE 15W-40).

Engine Oil Capacity:

Approx. 6.5 Liters (6.9 US Quarts) with filter change.

Coolant Type:

Ethylene Glycol based antifreeze, typically blue or green. BMW coolant (G48) or equivalent. Manual will provide specific BMW part number.

Brake Fluid Type:

DOT 3 or DOT 4, low viscosity, high boiling point brake fluid.

Common Failures 733I 735I:

Cooling system (radiator, hoses, water pump), fuel delivery (fuel pump, injectors), ABS control module issues, door seal degradation, climate control blower motor failure, occasional head gasket issues on high mileage engines.

Maintenance Tips:

Regular oil changes with quality oil, attention to cooling system integrity, and proactive replacement of rubber components (hoses, bushings) are crucial for longevity.

📚 Vehicle History

Brand Legacy:

BMW (Bayerische Motoren Werke AG) is renowned for its 'Ultimate Driving Machine' ethos, emphasizing performance, engineering excellence, and driver engagement.

E23 Introduction:

The E23 generation of the BMW 7 Series debuted in 1977 as the successor to the E12. The 733i was introduced in 1977, with the 735i replacing it in 1980 (or later, depending on market introduction for the update).

E23 Facelift:

Received a significant facelift around 1983, incorporating updated aerodynamics, interior refinements, and engine management (Motronic for the 735i).

E23 Successor:

The E23 was succeeded by the E32 7 Series generation in 1986.

Production Years:

1977-1986 (for E23 platform)

Manufacturing Location:

Dingolfing, Germany

🏆 Awards & Recognition

Vehicle Reputation:

The E23 7 Series was critically acclaimed for its engineering, build quality, and driving refinement, solidifying BMW's position in the luxury sedan market.

Manual Value:

Highly valuable for owners and mechanics, providing in-depth, factory-accurate information essential for maintaining these classic German luxury vehicles.