🏷️ Basic Information

Make:

Mercedes-Benz

Model:

W123 280CE

Year:

1976-1985

Chassis Code:

W123

👋 Introduction

Positioning:

The W123 generation represented Mercedes-Benz's commitment to robust engineering, luxury, and durability, establishing a strong reputation in the executive sedan and coupe market. The 280CE, with its refined engine, offered a balance of performance and comfort.

Competitors:

Competed with luxury sedans and coupes from BMW (e.g., 5 Series), Audi, Jaguar, and Volvo during its production run.

Features:

Known for its build quality, comfortable ride, advanced safety features for its era (e.g., optional ABS), and sophisticated styling. The 280CE variant specifically featured the smooth M110 inline-six engine.

Audience:

Primarily mechanical technicians, but also accessible to experienced DIY enthusiasts who are familiar with general automotive practices.

📋 Manual Details

Primary Coverage:

Repair and overhaul of Mercedes-Benz W123 280CE models

Total Pages:

559

Type:

Workshop Service Manual

Language:

English

File Format:

PDF

📖 Manual Coverage

Engine:

Comprehensive coverage, including disassembly and reassembly

Fuel System:

Detailed procedures for fuel injection, carburetion (if applicable to specific engine variants), and fuel delivery

Ignition:

Ignition system components, timing, and troubleshooting

Lubrication System:

Oil pump, oil passages, lubrication schedules, and oil specifications

Exhaust:

Exhaust system components, manifold, catalytic converter (if applicable), and mufflers

Electrical System:

Wiring diagrams, charging system, starting system, lighting, and accessory electrical components

Body:

Body panels, doors, windows, interior trim, and associated hardware

Transmission:

Manual and automatic transmission overhaul, removal, and installation

Brakes:

Brake system diagnostics, repair, and component replacement (e.g., pads, rotors, calipers, lines)

Suspension:

Front and rear suspension components, alignment, and troubleshooting

Steering:

Steering gear, power steering system, and linkage components

Cooling System:

Radiator, water pump, thermostat, cooling fan, hoses, and coolant flow.

Emission Controls:

Catalytic converter operation (if equipped), exhaust gas recirculation (EGR) systems (if applicable).

Climate Control:

Heating, ventilation, and air conditioning system components, operation, and repair.

Differentials:

Rear differential maintenance and repair.

Wheel Bearings:

Front and rear wheel bearing service and replacement.

Routine Maintenance:

Tune-ups, fluid changes, filter replacements, and general servicing

Diagnostic Troubleshooting:

Step-by-step guidance for identifying and resolving common and uncommon faults

Component Removal Installation:

Detailed instructions for removing and reinstalling all major vehicle components

Assembly Disassembly:

In-depth procedures for breaking down and rebuilding major assemblies like the engine and transmission

Proprietary Component Repair:

Instructions for components manufactured by Mercedes-Benz and potentially third-party suppliers, with emphasis on understanding their function

Trouble Shooting Charts:

Diagnostic flowcharts and symptom-based troubleshooting guides.

Torque Specifications:

Detailed torque values for all critical fasteners, essential for proper assembly and safety.

Special Tool Identification:

References to and illustrations of Mercedes-Benz specific tools required for certain adjustments and repairs.

Depth:

Advanced diagnostics and comprehensive repair procedures, suitable for professional technicians and knowledgeable enthusiasts

Diagnostic Methods:

Emphasis on understanding system functions and applying logical diagnostic steps.

📊 Manual Specifications

Quality:

High-resolution PDF, ensuring clarity of text and diagrams

Searchable:

Likely text-searchable if created from digital source, enhancing usability.

Printable:

Yes

Type:

N/A (Digital PDF format)

Type:

N/A (Digital PDF format)

⚙️ Engine Specifications

Engine Code:

M110 (typically)

Configuration:

2.8L Inline-6 Cylinder, DOHC

Horsepower:

Approximately 185 PS (136 kW) depending on market and injection system (e.g., Bosch K-Jetronic)

Torque:

Approximately 23.5 kgm (230 Nm; 170 lb-ft) depending on market and injection system

Injection System:

Bosch K-Jetronic (Continuous Injection System)

Engine Management:

Mechanical fuel injection system (K-Jetronic) managed by the fuel distributor and airflow sensor.

🔧 Transmission

Type:

4-speed manual transmission (often standard in some markets)

Type:

4-speed or 5-speed automatic transmission (e.g., 722.1 or 722.3)

Features:

Torque converter lock-up in automatics for improved fuel efficiency

Fluid Capacity Auto:

Approximately 7-8 liters for automatic transmissions. (Consult manual for exact capacity).

📐 Dimensions

Coupe Wheelbase:

Approximately 2795 mm (110.0 in)

Coupe Length:

Approximately 4735 mm (186.4 in)

Coupe Width:

Approximately 1790 mm (70.5 in)

Coupe Height:

Approximately 1420 mm (55.9 in)

Curb Weight:

Approximately 1450-1550 kg (3197-3417 lbs) depending on equipment

Gross Vehicle Weight Rating:

Not specified, but generally in the range of 1900-2000 kg.

🛡️ Safety Features

Era Ratings:

While formal crash test ratings as we know them today were less standardized, the W123 was renowned for its robust safety cell, crumple zones, and high build integrity.

Features:

Optional Anti-lock Braking System (ABS) became available on later models.

Features:

Reinforced passenger compartment, collapsible steering column, impact-absorbing interior materials, padded dashboard.

💡 Technology Features

Features:

Basic analog radio, often with cassette player options. Climate control systems, typically with manual or semi-automatic air conditioning. Power windows and central locking were available options.

Features:

Limited by modern standards; features like cruise control were available on higher trims or as options. Optional ABS on later models.

Features:

None by modern standards. Analog systems only.

🔧 Maintenance

Oil Change:

Typically every 5,000-10,000 km (3,000-6,000 miles) or 6-12 months, depending on driving conditions and oil type used. Consult manual for exact specifications.

Tune Up Interval:

Spark plugs, ignition timing, and fuel system checks typically every 20,000-40,000 km (12,000-25,000 miles).

Engine Oil:

API SG or higher, SAE 15W-40 or 10W-40 recommended for most conditions. Specific Mercedes-Benz specifications like MB 227.1 or 228.1 may apply. (Consult manual for precise grade).

Coolant:

Ethylene glycol based antifreeze/coolant, mixed 50/50 with distilled water. MB-Approval 325.0 or equivalent.

Transmission Fluid Auto:

Dexron II or equivalent. (Specific MB-Approval like MB 236.2 may apply).

Brake Fluid:

DOT 3 or DOT 4.

Power Steering Fluid:

Hydraulic fluid, often Dexron II or equivalent. (Consult manual for specific MB-Approval).

Gear Oil Manual:

GL-4 or GL-5 rated gear oil, SAE 75W-90 or 80W-90 recommended. (Consult manual for exact specifications).

Common Problems:

Potential for rust in common W123 areas (wheel arches, door bottoms, window frames), aging fuel lines (especially with modern fuels), vacuum line degradation affecting climate control and engine functions, and wear in suspension bushings and ball joints.

Electrical Issues:

Fraying wiring harnesses, aging vacuum-actuated systems (HVAC, central locking), and corroded electrical connectors.

📚 Vehicle History

Heritage:

Mercedes-Benz has a long-standing heritage of engineering excellence, luxury, and pioneering automotive safety and technology.

Evolution:

The W123 succeeded the W114/W115 series and was produced from 1975 to 1986 (sedan/wagon), with the coupe (C123) starting in 1977. The 280CE model was a key part of the coupe lineup, offering a more powerful and refined option.

Design Philosophy:

The W123 was designed with an emphasis on longevity, reliability, and occupant safety, a hallmark of Mercedes-Benz engineering during this period.

Production Period:

1976-1985 (for W123 280CE coverage in this manual)

Manufacturing Locations:

Primarily Germany, with some assembly in other global locations.

🏆 Awards & Recognition

Recognition:

The W123 series, including the 280CE, consistently received acclaim for its build quality, durability, and comfort, often cited in automotive media as a benchmark for its era. It's frequently recognized by classic car enthusiasts for its timeless design and engineering integrity.