🏷️ Basic Information

Make:

Mercedes-Benz

Model:

W114/W115

Year:

1973

Chassis Code:

W114/W115

👋 Introduction

Target Audience:

Mercedes-Benz W114/W115 owners, independent repair shops, classic car enthusiasts, DIY mechanics.

Segment Positioning:

Positioned as a premium mid-size sedan and coupe, bridging the gap between the smaller W115 and the larger S-Class (W108/W109).

Value Proposition:

Provides definitive, vehicle-specific information identical to what dealership technicians use, enabling accurate and efficient repair, maintenance, and diagnosis. Significantly more detailed and accurate than generic repair guides.

Digital Advantage:

Easy navigation, search functionality, ability to print specific sections, protection from physical wear and tear.

Content Detail:

Complete A-Z coverage for all models and repairs, including detailed diagrams, illustrations, and wiring schematics.

📋 Manual Details

Primary Coverage:

Service, Repair, Maintenance, Diagnosis

Model Variants Covered:

All W114 and W115 models

Estimated Page Count:

Varies by specific factory publication, but comprehensive digital versions typically offer equivalent detail to hundreds of printed pages.

Type:

Factory Service and Repair Manual

Language:

English

Format:

PDF (Digital)

📖 Manual Coverage

Engine:

Detailed diagnostics, overhaul, timing, fuel system, cooling, lubrication, ignition, starting, charging systems.

Transmission:

Manual and automatic transmission service, overhaul, fluid specifications, adjustments, clutch service.

Brakes:

Hydraulic system, calipers, drums, parking brake, fluid specifications, bleeding procedures.

Suspension Steering:

Front and rear suspension components, steering gear, power steering, alignment specifications, wheel bearings.

Electrical:

Complete wiring schematics, component testing, lighting, instrumentation, power distribution, starter, alternator.

Body Interior:

Body panels, doors, windows, locks, seats, upholstery, glass, mirrors, climate control, wipers, washers.

Fuel Emission:

Fuel delivery, carburetor/injection systems (model dependent), emission control systems, specifications.

Chassis And Body:

Frame construction, body mounting, door mechanisms, hinges, latches, hood, trunk lid, windshield, rear glass, mirrors.

Climate Control:

Heater core, ventilation system, blower motor, control linkages, and any optional air conditioning systems.

Fuel And Emission Control:

Detailed coverage of fuel tanks, lines, pumps, filters, carburetors or early fuel injection systems, and emission control devices as mandated by regulations of the era.

Drive Axle And Differential:

Service procedures for rear axle assembly, driveshaft, universal joints, and differential unit, including fluid types and capacities.

Maintenance Schedule:

Regular maintenance intervals, fluid changes, filter replacements, lubrication points.

Troubleshooting:

Diagnostic flowcharts, common problem identification, symptom-based troubleshooting.

Repair Procedures:

Step-by-step instructions for component removal, installation, and overhaul for all major systems.

Diagnostics:

Detailed procedures for diagnosing electrical and mechanical faults.

Component Replacement:

Detailed guides for replacing parts such as alternators, starters, fuel pumps, water pumps, radiator, exhaust components.

Adjustments:

Carburetor idle speed and mixture, valve clearances, ignition timing, parking brake adjustment, clutch free play.

Depth:

Comprehensive, factory-level detail suitable for professional technicians and advanced DIY enthusiasts. Covers everything from basic maintenance to complete engine rebuilds and complex electrical diagnostics.

Specifications And Data:

Includes torque specifications for critical fasteners, engine bearing clearances, piston ring gaps, valve lift, timing marks, and wheel alignment angles.

📊 Manual Specifications

Compatibility:

Windows (Vista, XP, ME, 98, NT, 2000) and Mac compatible.

File Requirements:

Requires Adobe PDF Reader and Winzip (or equivalent extraction software).

Printability:

All pages are printable; allows for enlarged image printing.

Binding:

Digital (PDF) - No physical binding.

Digital Features:

Searchable text, zoomable images, hyperlinked sections (if applicable to specific PDF creation).

⚙️ Engine Specifications

Engine Variants:

Covers gasoline (e.g., M115, M114 inline-4 and inline-6) and diesel (e.g., OM615, OM616, OM617 inline-4 and inline-5) engines.

Engine Performance Details:

Includes specifications for horsepower, torque, bore, stroke, compression ratios for various engine options.

Fuel System Coverage:

Details on Solex, Zenith, or Bosch fuel injection systems (depending on specific model and market), fuel pumps, filters, and pressure specifications.

Diesel Engine Details:

OM615 (2.0L, 2.2L), OM616 (2.4L), OM617 (3.0L) naturally aspirated diesel engines, known for their durability and fuel efficiency.

Gasoline Engine Details:

M115 (2.0L, 2.3L inline-4), M114 (2.5L inline-6), M110 (2.8L inline-6, introduced later) gasoline engines.

🔧 Transmission

Manual Transmission Options:

Details for 4-speed and 5-speed manual transmissions common in W114/W115 models.

Automatic Transmission Options:

Coverage for the Mercedes-Benz 3-speed automatic transmission (e.g., 720) with torque converter.

Transmission Fluid Specs:

Specific automatic transmission fluid (ATF) types and capacities, manual transmission gear oil specifications.

Gear Ratios:

Manual and automatic transmission gear ratios are provided for different model configurations.

📐 Dimensions

Wheelbase:

W114: 2800mm (110.2 in); W115: 2750mm (108.3 in)

Length:

Approx. 4740 mm (186.6 in)

Width:

Approx. 1750 mm (68.9 in)

Height:

Approx. 1420 mm (55.9 in)

Curb Weight:

Varies significantly by engine and equipment, typically ranging from 1300kg to 1500kg (2866 lbs to 3307 lbs).

🛡️ Safety Features

Safety Features Design:

While formal crash ratings of the modern era are not applicable, the W114/W115 featured a robust safety cage, crumple zones, and safety glass.

Active Safety Systems:

Disc brakes on front wheels, optional power-assisted steering, safety-designed steering column.

Passive Safety Features:

Laminated front windshield, side-impact protection beams in doors, padded dashboard and steering wheel hub.

💡 Technology Features

Audio System:

Factory provision for AM/FM radio and potentially cassette player. Manual covers their installation and basic troubleshooting.

Cruise Control:

Optional cruise control systems were available; manual details their operation and service.

Connectivity Features:

Not applicable in the modern sense. Focus is on mechanical and electrical systems.

🔧 Maintenance

Oil Change Interval:

Typically every 5,000 km (3,000 miles) or 6 months, depending on driving conditions. Check manual for exact specifications.

Tune Up Interval:

Spark plugs, points, and condenser typically checked/replaced every 10,000-20,000 km (6,000-12,000 miles).

Engine Oil Type:

API SF/CD or SG/CD rated oils, viscosity dependent on climate (e.g., 10W-40, 20W-50). Consult manual for precise recommendations.

Coolant Type:

Ethylene glycol-based antifreeze/coolant. Specific mix ratio and type detailed in manual.

Brake Fluid Type:

DOT 3 or DOT 4 hydraulic brake fluid (specified by Mercedes-Benz).

Power Steering Fluid:

Specific hydraulic fluid or ATF as per Mercedes-Benz specifications for power steering systems.

Common Wear Items:

Brake system components (calipers, master cylinder), fuel system components (especially in older, unrestored vehicles), suspension bushings, exhaust systems, vacuum hoses.

Diesel Specific Issues:

Glow plug system reliability, injector pump maintenance.

Electrical System Concerns:

Aging wiring harnesses, corrosion in connectors, and the reliability of older electrical components (e.g., headlight relays, ignition modules).

📚 Vehicle History

Mercedes Benz Legacy:

Part of Mercedes-Benz's legacy of building durable, well-engineered, and luxurious vehicles. The W114/W115 was a successful model that brought Mercedes-Benz quality to a broader market segment.

W114 W115 Development:

Introduced in 1968, these models replaced the W110 'Fintail' series. The W114 designated the more powerful 6-cylinder models, while W115 designated the 4-cylinder and diesel variants. Both shared a common body shell design.

Chassis Design Influence:

The W114/W115 chassis introduced a more modern unibody construction with an integrated subframe for the engine and front suspension, a departure from older body-on-frame designs.

Production Period:

1968-1976

🏆 Awards & Recognition

Model Reputation:

The W114/W115 is widely recognized for its build quality, reliability, and comfortable ride, establishing a strong reputation for Mercedes-Benz in its segment. Often referred to as the 'Stroke Eight'.