🏷️ Basic Information Identification Make: Mercedes-Benz Model: 500 SEL Model Code: W126 Year Range Covered: 1984-1985 Codes Chassis Code: W126 Engine Code Typical: M117 (5.0L V8) 👋 Introduction Market Position Market Segment: Full-size luxury sedan, flagship model of Mercedes-Benz for its era Target Audience: Affluent professionals, executives, discerning car enthusiasts Competitive Analysis Key Competitors: BMW 7 Series, Cadillac Eldorado/Seville, Jaguar XJ Series, Rolls-Royce Silver Spirit Key Features Distinctive Attributes: Exceptional build quality, advanced engineering, luxurious comfort, powerful V8 engine, sophisticated styling Manual Value Proposition: Enables owners and technicians to maintain and repair a complex, high-value classic vehicle with accuracy and confidence. 📋 Manual Details Coverage Areas Coverage Scope: Comprehensive service and repair Page Count Estimated Pages: Varies by publisher, typically 1000+ for factory equivalent Manual Type Type: Factory Service Manual / Workshop Manual Language Language: English (typically translated from German originals) Format Format: Print or Digital (PDF) 📖 Manual Coverage Systems Covered Engine Mechanical: Full engine overhaul, component testing, timing, sealing Engine Management: Fuel injection (K-Jetronic/KE-Jetronic), ignition system, emission controls, diagnosis Transmission Mechanical: Automatic transmission (4-speed 722.3) overhaul, adjustments, troubleshooting Transmission Electrical: Transmission control module (if applicable), sensors, solenoids Brakes: Hydraulic system, ABS (Anti-lock Braking System), brake pads, rotors, lines, calipers Suspension: Independent suspension, front and rear, shock absorbers, springs, control arms, steering linkage Steering: Power steering system, steering gearbox, linkages, diagnosis Electrical System: Wiring diagrams, charging system, starting system, lighting, accessories, fuse/relay identification Climate Control: HVAC system, A/C compressor, R12 refrigerant, heater core, blower motor, controls Body And Trim: Body panels, doors, windows, locks, interior trim, convertible top (if applicable for SEC variant, though SEL is sedan) Chassis: Frame construction, body mounts, undercoating Procedures Included Routine Maintenance: Oil changes, filter replacements, spark plugs, belts, hoses, fluid checks Diagnostic Procedures: Troubleshooting charts, symptom-based diagnostics, component testing Repair Procedures: Step-by-step instructions for all major mechanical and electrical components Rebuilding Procedures: Detailed instructions for engine, transmission, and major component rebuilds Restoration Guidance: Information applicable to refurbishing and restoring classic Mercedes-Benz vehicles Technical Depth Depth: Expert level, suitable for professional mechanics and advanced DIY enthusiasts Diagnostic Tools: Procedures often require specialized Mercedes-Benz diagnostic equipment of the era 📊 Manual Specifications File Format Digital Format: PDF (Searchable, printable pages) Print Quality Print Quality: High-resolution scans of original factory publications Binding Type Binding Type: Perfect bound or spiral bound (for print versions) Paper Type Paper Type: Durable, high-quality paper suitable for workshop environments (for print versions) ⚙️ Engine Specifications Primary Engine Engine Type: V8, SOHC (Single Overhead Camshaft) Displacement: 5.0 Liters (4973 cc) Bore X Stroke: 96.0 mm x 85.0 mm Compression Ratio: 8.0:1 (approx.) Performance Horsepower: 180-230 hp (depending on market and specific tuning) Torque: 270-320 lb-ft (depending on market and specific tuning) Fuel System Fuel Delivery: Bosch K-Jetronic or KE-Jetronic fuel injection Fuel Type: Unleaded gasoline (premium, 91 octane or higher recommended) Fluid Capacities Engine Oil Capacity: 8.5 Liters (with filter) - consult manual for exact specification (e.g., 15W-40, 10W-40) 🔧 Transmission Standard Transmission Type: 4-speed automatic Transmission Model: 722.3 (or equivalent) Optional Optional Transmission: None offered for 500 SEL in this era Features Transmission Fluid Type: ATF Dexron III or equivalent (consult manual for exact MB spec, e.g., MB 236.3) Transmission Fluid Capacity: Approximately 7.0-8.0 Liters (dry fill, varies with torque converter fill) 📐 Dimensions Exterior Length: Approx. 5020 mm (197.6 in) Width: Approx. 1790 mm (70.5 in) Height: Approx. 1420 mm (55.9 in) Wheelbase: Approx. 2935 mm (115.6 in) Weights Curb Weight: Approx. 1750-1850 kg (3850-4070 lbs) 🛡️ Safety Features Ratings Crash Test Data: Limited formal crash test data from modern standards, but known for robust chassis and passenger cell construction. Active Features Active Safety Features: ABS (Anti-lock Braking System), advanced suspension geometry, powerful disc brakes Passive Features Passive Safety Features: Reinforced passenger cell, crumple zones, energy-absorbing steering column, dual front airbags (late models/optional), seat belt pre-tensioners 💡 Technology Features Infotainment Audio System: Original Becker or Blaupunkt radios, often with cassette decks. Upgrades are common. Features: Analog climate controls, power accessories (windows, seats, mirrors), cruise control, central locking. Driver Assistance Advanced Features: ABS, cruise control, potentially headlight washers and limited slip differential (LSD) as options. Connectivity Connectivity Options: No modern connectivity features like Bluetooth or USB. Antennas are typically power-operated. 🔧 Maintenance Service Intervals Oil Change Interval: Typically 10,000-15,000 km (6,000-10,000 miles) or annually, depending on usage and oil quality. Consult manual. Transmission Service: Fluid and filter change every 40,000-60,000 km (25,000-40,000 miles). Consult manual. Major Service Intervals: Spark plugs, fuel filter, air filter, cooling system flush at specified intervals (e.g., 60,000-100,000 km). Fluid Specifications Coolant Type: Mercedes-Benz approved G48 coolant (phosphate-free, ethylene glycol based) or equivalent. Brake Fluid Type: DOT 3 or DOT 4 brake fluid (ensure high boiling point). Power Steering Fluid: Pentosin CHF 11S or equivalent approved hydraulic fluid. Known Issues Common Wear Items: Engine mounts, suspension bushings,...
Aging wiring insulation, corroded connectors, failing relays, and vacuum leaks are common sources of intermittent issues.
K Jetronic Issues:
Fuel distributor leaks, control pressure regulator (WUR) failure, and air flow meter sensor wear can affect fuel mixture.
📚 Vehicle History
Brand Heritage
Mercedes Benz Legacy:
Long-standing reputation for engineering excellence, luxury, safety, and durability.
Model Evolution
W126 Development:
Successor to the W116 S-Class, introduced in 1979, represented a significant leap in aerodynamics, safety, and comfort for its time.
500 Sel Positioning:
The 500 SEL was the high-performance, long-wheelbase version of the W126, offering enhanced rear passenger space and comfort.
Production
Production Period:
1979-1991 (W126 generation)
Manufacturing Location:
Germany (primarily Sindelfingen)
🏆 Awards & Recognition
Recognitions
Industry Accolades:
The W126 generation was widely praised for its engineering and luxury, often cited in 'Car of the Year' lists and luxury segment awards during its production run.
Ratings
Reliability Perception:
When properly maintained with quality parts, these vehicles are known for exceptional longevity. However, neglect leads to costly repairs.