Positioning:
Essential resource for owners and independent mechanics of the Mercedes-Benz W123 generation, offering factory-level technical information.
Comparison To Print:
Provides the convenience of instant digital access and printability, often at a lower cost than traditional printed manuals.
Instant Access:
Immediate download upon purchase, allowing users to start working without delay.
Comprehensiveness:
Offers complete information on maintenance, diagnostics, and repair, directly from manufacturer data.
User Support:
Customer support offered for any difficulties in finding information within the manual.
Digital Advantage:
Emphasizes the benefits of digital manuals for environmental friendliness and efficiency.
Covered Years:
1981, 1982, 1983, 1984, 1985, 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993
Estimated Page Count:
Varies based on specific engine/body style, but generally extensive for a full service manual.
Type:
Service and Repair Manual
Format:
Digital (ZIP archive, likely PDF or similar, printable)
Engine:
Comprehensive coverage including diagnostics, maintenance, repair, rebuilds for gasoline and diesel variants.
Fuel System:
Carburetor and fuel injection systems (Bosch K-Jetronic, diesel injection pumps).
Transmission:
Manual and automatic transmission service, repair, and fluid specifications.
Drivetrain:
Front suspension, rear axle, driveshafts, differentials.
Brakes:
Hydraulic system, ABS (if equipped), disc and drum brake service, component replacement.
Steering:
Power steering system, steering column, linkages.
Suspension:
Front and rear suspension components, shock absorbers, springs, alignment.
Electrical System:
Wiring diagrams, lighting, ignition system, starter, alternator, battery, fuses, relays.
Body:
Bodywork repair, panel replacement, doors, windows, locks, glass replacement.
HVAC:
Heating, ventilation, and air conditioning system service and repair.
Interior:
Dashboard, upholstery, trim, seat adjustment.
Maintenance:
Routine maintenance, oil changes, filter replacements, fluid checks and top-offs.
Diagnostics:
Troubleshooting guides, symptom-based diagnostics, fault code interpretation (if applicable).
Repair:
Step-by-step repair procedures for all major mechanical and electrical components.
Disassembly Assembly:
Detailed instructions for component removal and reinstallation.
Rebuilding:
Engine and transmission rebuild procedures.
Adjustments:
Valve adjustments, idle speed adjustments, timing adjustments.
Cleaning:
Cleaning procedures for various components.
Depth:
Comprehensive, covering basic maintenance to complete engine/transmission overhauls and advanced diagnostics.
Diagrams Illustrations:
Includes detailed diagrams, schematics, and illustrations for clarity.
Expert Knowledge:
Leverages skilled mechanics' know-how for practical solutions.
Common Gasoline Engines:
M102 (2.0L, 2.3L I4), M110 (2.8L I6), M123 (2.5L I6)
Common Diesel Engines:
OM615 (2.0L, 2.2L I4 diesel), OM616 (2.4L I4 diesel), OM617 (3.0L, 3.0L Turbo I5 diesel)
Horsepower Range:
Approximately 70 hp (diesel) to 180 hp (petrol, depending on engine and tuning).
Torque Range:
Varies significantly by engine; diesel engines are known for strong low-end torque.
Gasoline Injection:
Bosch K-Jetronic continuous injection system on many later models.
Diesel Fuel System:
Bosch inline fuel injection pumps or distributor injection pumps.
Manual Transmission Options:
4-speed and 5-speed manual transmissions were available.
Automatic Transmission Options:
3-speed and 4-speed automatic transmissions (e.g., 722.1, 722.3).
Automatic Features:
Often featured torque converters and modes like 'Economy' and 'Power'.
Body Styles:
Sedan (W123), Coupe (C123), Estate/Wagon (S123), Limousine (V123).
Wheelbase:
Varies by body style (e.g., Sedan: approx. 2795 mm, Estate: approx. 2850 mm).
Curb Weight Range:
Approximately 1300 kg to 1700 kg, depending on engine and body style.
Crash Test History:
While formal crash test ratings like modern NCAP were not prevalent, the W123 was renowned for its robust construction and safety features for its era.
Braking System:
Four-wheel disc brakes on many models, optional ABS on later versions.
Construction:
Reinforced passenger cell, crumple zones, safety glass.
Steering Column:
Collapsible steering column.
Original Features:
Basic analog radio, cassette player (optional), mechanical odometer, basic climate control.
Original Features:
Power steering, cruise control (optional), ABS (optional on later models).
Original Features:
Limited to basic antenna input for radio.
Oil Change Interval:
Typically every 5,000-10,000 km or annually, depending on engine type and oil used (check manual for specifics).
Filter Replacement:
Air filter, fuel filter, oil filter typically replaced during regular servicing.
Engine Oil:
Varies by engine; common specifications include SAE 10W-40 or 15W-40 for diesel, and SAE 10W-40 or 20W-50 for gasoline. API service categories like SF, SG. Specific viscosity and API rating crucial.
Coolant:
Ethylene glycol-based antifreeze with corrosion inhibitors, typically mixed 50/50 with distilled water. MB Specification 325.0.
Transmission Fluid Auto:
Dexron II or equivalent is often specified for automatic transmissions (e.g., MB Specification 236.3).
Brake Fluid:
DOT 3 or DOT 4 glycol-based brake fluid. MB Specification 331.0.
Power Steering Fluid:
Typically hydraulic fluid meeting MB Specification 236.3 (Dexron II equivalent).
Common W123 Issues:
Rusting (especially wheel arches, sills, door bottoms), vacuum line issues (central locking, climate control), injector pump seal leaks (diesel), idle control problems (gasoline).
Engine Longevity:
Diesel engines are exceptionally durable if properly maintained, often exceeding 500,000 km.
Mercedes Benz Legacy:
Part of Mercedes-Benz's reputation for engineering excellence, durability, and build quality.
W123 Development:
Evolved from the W114/W115 series, focusing on improved aerodynamics, safety, and powertrain options.
Production Years:
1976-1985 (original production). The manual covers models up to 1993, reflecting the longevity and continued operation of these vehicles.
Key Variants:
Famous for its diesel engines (especially the OM617 turbo diesel) and its reputation for reliability.
