Target Audience:
Mercedes-Benz W123 owners, independent repair shops, classic Mercedes enthusiasts
Differentiation:
Official dealership-level repair data, not generic DIY guides
Uniqueness:
Covers all W123 variants and models within the specified year range
Authority:
Authoritative source for maintenance, service, and repair procedures
Scope:
Comprehensive: All models, all repairs A-Z
Estimated Page Count:
Varies by specific edition, typically 500+ pages
Type:
Service and Repair Manual
Format:
Digital (e.g., PDF) or Printed
Engine Service And Repair:
Detailed procedures for all gasoline and diesel engines
Transmission Service And Repair:
Manual and automatic transmission overhaul and repair
Fuel And Emission Systems:
Carburetor and fuel injection systems, emissions controls
Electrical System:
Wiring diagrams, starter, alternator, ignition, lighting, accessories
Brake System:
Hydraulic systems, ABS (if applicable to later models), brake component replacement
Suspension And Steering:
Front and rear suspension, power steering, alignment specifications
Body And Chassis:
Body panel repair, structural integrity, chassis components
Heating And Air Conditioning:
HVAC system diagnosis and repair
Routine Maintenance:
Oil changes, filter replacements, fluid checks, tune-ups
Diagnostic Troubleshooting:
Systematic fault finding and repair procedures
Component Replacement:
Step-by-step guides for major component removal and installation
Engine Rebuilding:
Detailed specifications and procedures for engine overhaul
Electrical Diagnostics:
Using wiring diagrams for troubleshooting
Torque Specifications:
Precise tightening specifications for all critical fasteners
Depth:
Vehicle Specific, Technician Level
Accuracy:
Factory-level accuracy and detail
Searchability:
Likely searchable text if digital PDF
Digital Format Advantages:
Easy searchability, instant access, printable pages
Illustrations:
High-quality diagrams, schematics, and photographs
Binding:
Durable binding for frequent use (for print versions)
Paper Quality:
Durable, shop-grade paper stock (for print versions)
Available Engines Overview:
Wide range of inline-4 and inline-6 gasoline (M115, M123, M110) and diesel (OM615, OM616, OM617) engines
2.4L Diesel (Om616):
Displacement: 2.4 liters, Power: ~70 hp, Torque: ~134 Nm
3.0L Diesel (Om617):
Displacement: 3.0 liters, Power: ~80-88 hp (turbocharged variants available later), Torque: ~173-192 Nm
2.0L Gasoline (M115):
Displacement: 2.0 liters, Power: ~94 hp, Torque: ~150 Nm
2.8L Gasoline (M110):
Displacement: 2.8 liters, Power: ~137-185 hp (dual overhead cam), Torque: ~221-250 Nm
Acceleration Characteristics:
Designed for durability and comfort, not outright performance; varies significantly by engine and transmission
Gasoline Fuel Delivery:
Carburetor (e.g., Solex, Zenith) for earlier models, Bosch K-Jetronic fuel injection for later gasoline models
Diesel Fuel Delivery:
Bosch inline injection pumps
Standard Transmission:
4-speed or 5-speed manual transmission
Optional Transmission:
3-speed or 4-speed automatic transmission (e.g., 722.1, 722.3 series)
Automatic Transmission Features:
Selectable modes (e.g., 'S' for Standard, 'E' for Economy)
Body Styles:
Sedan (4-door), Sedan (2-door), Estate/Wagon (T-model), Coupe (C123), often referred to as 'CE'
Overall Length:
Varies by body style, e.g., Sedan approx. 4720-4788 mm
Overall Width:
Varies by body style, e.g., Sedan approx. 1790 mm
Wheelbase:
Varies by body style, e.g., Sedan approx. 2795 mm
Cargo Capacity Wagon:
Generous for its era, particularly the T-model variant
Curb Weight:
Approximately 1400-1700 kg depending on engine and body style
Historical Safety Context:
Considered very safe for its era, with robust chassis construction
Braking System Design:
Four-wheel disc brakes on many models, with power assistance
Body Structure:
Reinforced passenger compartment, crumple zones
Steering Column:
Collapsible steering column
Original Infotainment:
Basic radio (mono or stereo), cassette player in some higher trims
Advanced Features For Era:
Power steering, cruise control (optional on some models), central locking (vacuum operated)
Connectivity Features:
N/A (pre-digital era)
Oil Change Interval:
Typically every 5,000-10,000 km or annually, depending on engine and oil type
Major Service Milestones:
Key checks and replacements at 20,000 km, 40,000 km, 80,000 km intervals
Engine Oil Specification:
Refer to manual for specific API service classifications (e.g., API SG for gasoline, CD for diesel) and viscosity grades (e.g., SAE 10W-40, 15W-40)
Coolant Specification:
Mercedes-Benz Approved Antifreeze/Coolant Concentrate (e.g., G48)
Automatic Transmission Fluid:
ATF Dexron III or equivalent (refer to specific transmission model)
Brake Fluid Specification:
DOT 3 or DOT 4
Common W123 Issues:
Rust (wheel arches, sills, door bottoms), injector pump seal leaks (diesel), vacuum door lock system issues, oil cooler leaks, climate control (if fitted)
Example Oil Filter Part Number:
Mann-Filter HU 718/1 K or equivalent (engine dependent)
Example Air Filter Part Number:
Mann-Filter C 2420 or equivalent (engine dependent)
Mercedes Benz Reputation:
Renowned for engineering excellence, durability, and build quality
Predecessor:
Mercedes-Benz W114/W115 (Stroke Eight)
Successor:
Mercedes-Benz W124 E-Class
Production Plants:
Mainly Bremen, Germany; also South Africa, Argentina, and others
Total Production Units:
Over 1.6 million units across all body styles
Market Impact:
Highly successful model that solidified Mercedes-Benz's reputation in the executive sedan market
