🏷️ Basic Information Identification Make: Mercedes-Benz Model: 450 SEL Chassis Code: W116 Generation Generation Designation: First Generation W116 👋 Introduction Market Position Positioning: The Mercedes-Benz W116 series represented the pinnacle of luxury and engineering in its era, targeting affluent buyers seeking comfort, performance, and prestige. The 450 SEL was the long-wheelbase variant, emphasizing rear passenger space and luxury appointments. Competitive Analysis Competitors: Competed with other high-end luxury sedans of the period such as the Rolls-Royce Silver Shadow, Bentley T-Series, Jaguar XJ, and Cadillac Eldorado. Key Features Features: Renowned for its robust build quality, sophisticated suspension, powerful V8 engine, and advanced safety features for its time, including a crumple zone design. 📋 Manual Details Coverage Areas Applicable Years: 1973, 1974, 1975, 1976, 1977, 1978, 1979, 1980 Page Count Estimated Page Count: Extensive (Exact count not specified, but implies comprehensive coverage) Manual Type Type: Service Repair Workshop Manual Language Language: English Format Format: PDF Download 📖 Manual Coverage Systems Covered Engine Mechanical: Complete overhaul, troubleshooting, diagnostics, specifications Engine Electrical: Ignition system, starting and charging, ECU (if applicable), wiring diagrams Emission Control: Components, testing, and servicing of emission control systems Fuel System: Fuel injection (Bosch K-Jetronic likely), fuel pump, injectors, lines, tank Clutch System: Disc, pressure plate, release bearing, hydraulics (for manual transmission) Manual Transaxle: Gearbox overhaul, shifting mechanisms, lubrication Automatic Transaxle: Transmission servicing, hydraulic system, torque converter, control adjustments Driveshaft Axle: U-joints, CV joints, differential, axle shafts, wheel bearings Suspension System: Front and rear suspension components, springs, shock absorbers, bushings, alignment Steering System: Power steering pump, gearbox, steering linkage, column, adjustments Restraint System: Seat belts, pre-tensioners (if applicable), airbag systems (if equipped) Brake System: Hydraulic system, calipers, rotors, pads, lines, parking brake, ABS (if applicable) Body Interior Exterior: Panel replacement, trim, doors, windows, upholstery, seals Body Electrical: Lighting, instrumentation, power accessories, central locking, wiring diagrams HVAC: Heating, ventilation, air conditioning system components, refrigerant, servicing Procedures Included Maintenance: Routine service, oil changes, filter replacements, tune-ups, fluid checks Troubleshooting: Diagnostic procedures for common and uncommon faults Repair: Step-by-step repair instructions for all major systems Diagnostics: Detailed diagnostic trees and symptom-based troubleshooting Specifications: Torque values, clearances, fluid capacities, electrical specifications Wiring Schematics: Comprehensive electrical diagrams for all vehicle systems Body Work: Body panel repair, rust mitigation, interior trim installation/removal. Electrical Diagnostics: Detailed troubleshooting guides for electrical circuits, component testing, and common wiring faults. Tune Up: Ignition timing, spark plug replacement, fuel mixture adjustment (for K-Jetronic), idle speed control. Wheel Alignment: Specifications and procedures for front and rear wheel alignment. Air Conditioning Service: Refrigerant handling, component replacement (compressor, receiver/drier, expansion valve), leak detection. Torque Specifications: All critical engine, chassis, and body fasteners with detailed torque values. Troubleshooting Guides: Systematic approach to diagnosing common problems with clear step-by-step instructions. Technical Depth Depth: Comprehensive: Covers basic maintenance to full mechanical and electrical system overhauls, intended for professional mechanics and skilled DIYers. Scope: Covers everything from basic fluid changes and filter replacements to in-depth engine and transmission rebuilds, including diagnostics for electronic and mechanical systems of the era. 📊 Manual Specifications File Format Quality: High quality PDF, viewable on PC/Mac, phones, e-readers Print Quality Printability: Fully printable, allowing users to print specific pages as needed. Binding Type Binding: N/A (Digital PDF format) Paper Type Paper Type: N/A (Digital PDF format) ⚙️ Engine Specifications Primary Engine Engine: M117.982 (4.5L V8 SOHC) Performance Horsepower: Approximately 180-225 hp (SAE Gross, depending on market and emission controls) Torque: Approximately 230-270 lb-ft (SAE Gross) Fuel System Fuel Delivery: Bosch K-Jetronic mechanical fuel injection Displacement Displacement Cc: 4520 cc Bore Stroke Bore X Stroke Mm: 92.0 mm x 85.0 mm Compression Ratio Ratio: 8.0:1 (typical for US market) Cooling System Coolant Type: Mercedes-Benz Spec 320 (or equivalent antifreeze/water mix) 🔧 Transmission Standard Transmission Type: 3-speed Automatic (722.103, 722.118) Optional Transmission Type Optional: 4-speed Manual (available in some markets, less common) Features Fluid Type Automatic: Dexron II or equivalent (MB Spec 236.3) 📐 Dimensions Exterior Wheelbase Mm: 3050 mm (120.1 in) Length Mm: 5000 mm (196.9 in) Width Mm: 1790 mm (70.5 in) Height Mm: 1480 mm (58.3 in) Weights Curb Weight Kg: 1800-1900 kg (approx.) Gross Vehicle Weight Kg: 2350 kg (approx.) 🛡️ Safety Features Ratings Crash Test Performance: While formal crash ratings as we know them today didn't exist, the W116 was designed with advanced safety principles for its era, including a reinforced passenger cell and crumple zones. Active Features Active Safety: Four-wheel disc brakes, advanced suspension geometry for stable handling, power steering. Passive Features Passive Safety: Reinforced passenger compartment, energy-absorbing steering column, padded interior surfaces, seat belts. 💡 Technology Features Infotainment Infotainment System: Basic radio with analog tuner, often with cassette player. Speaker systems were typically modest by modern standards. Driver Assistance Driver Assistance Features: None by modern standards. Focus was on mechanical and structural safety. Connectivity Connectivity Features: Not applicable for this...