Mercedes W123 Repair - IFixit

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Mercedes W123 Table of Contents

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  • Diesel version models:

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Mercedes W123 Repair

The W123 chassis covers 240D's, 300D's, 300TD's, 280E's, and several other models of Mercedes coupes, sedans and wagons from model years 1977 to 1985.

Author: Nicolas Siemsen (and 5 other contributors) Create a Guide I Have This

Guides

Replacement Guides

Ash Tray

Battery Ground Cable

Brake Caliper, Front

Brake Caliper, Rear

Brake Disc, Rear

Brake Hose

Brake Line, Front Driver's Side

Brake Line, Rear

Brake Pad, Front

Brake Pads, Rear

Brake Reservoir Rubber Seals

Climate Control Unit v2

Engine Shock, Early Style Diesel

Front Seat

Front Seat Back Netting

Fuel Cap and Oil Cap Seal

Fuel Filler Neck Seal

Fuel Filter, Primary

Fuel Filter, Secondary

Fuel Injector Hard Line

Fuel Lines, Rear

Fuel Primer Pump

Fuel Return Line

Fuel Sending Unit

Glow Plug Fuse and Fuse Box, Early Style

Glow Plug, Pencil Style

High-pressure Power Steering Hose

Key head

Motor Mount

Over-voltage Protection Relay and Fuse

Power Steering Low Pressure Hose

Power Window Regulator, Rear

Radiator Hose

Short Bypass Coolant Hose

Spark plugs

Sway Bar Link

Tail/Reverse/Rear Turn Signal Bulb

Thermostat

Thermostat Housing Gasket, Diesel

Trunk Lock Vacuum Actuator

Turbo Air Cleaner Housing Bracket

Turbo Elbow Seals

Turn Signal Bulb, Front

Windshield Washer Fluid Bottle and/or Pump

Wood Trim

[Modification] Drivers Armrest

Disassembly Guides

Antenna Motor

Door Panel

Glove Box Liner

Instrument Cluster

Kick Panel

Mercedes Benz W123 Manual Mirror Disassembly

Mercedes W123 Door Sill Disassembly

Mercedes W123 Hazard Swich Disassembly

Techniques

Checking Power Steering Fluid in your Mercedes W123

Checking coolant level in your naturally aspirated diesel Mercedes W123

How to Change Mercedes W123 Power Steering Fluid and Filter

How to change Mercedes W123 coolant

How to check Mercedes W123 Fuses

How to check the Brake Fluid Level in your Mercedes W123

How to check the coolant level in your Turbo Diesel Mercedes W123

How to check the oil level in your Mercedes W123

How to clean Mercedes W123 Electric Ground contacts

How to fix Mercedes W123 "screw open" style window regulator

How to purge your Mercedes W123 diesel

Mercedes W123 disable security alarm

Mercedes W123 Basic Battery and Alternator Test Technique

Mercedes W123 Basic Diesel Blow-by Test Technique

Mercedes W123 Battery Maintenance

Mercedes W123 Brake Fluid Flush/Bleeding

Mercedes W123 Diesel Oil and Filter Change, Under Car

Mercedes W123 Diesel Pre-Purchase Inspection

Mercedes W123 Fuel Tank Strainer Maintenance

Mercedes W123 Glow Plug Test Technique

Mercedes W123 Jack Technique

Mercedes W123 Vacuum Lock System Diagnosis Technique

Mercedes W123 Wheel Removal Technique

Mercedes W123 fuel sending unit disassembly and cleaning

Repairing Mercedes W123 Door Lock Master Vacuum Switch

Repairing Mercedes W123 Door Lock Vacuum Actuator, Early Style

Repairing Mercedes W123 Fuel Door Lock Actuator

Repairing Mercedes W123 Odometer

Repairing Mercedes W123 Power Window Regulator, Rear

Repairing Mercedes W123 Window Regulator "Drill Open" Style Window Motor

Popular Forum Questions

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Tools

These are some common tools used to work on this device. You might not need every tool for every procedure.

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  Detailing Brush

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  Phillips #1 Screwdriver

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  Narwhal 6-in-1 Driver

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  Large Needle Nose Pliers

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  Metal Spudger

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  Digital Multimeter

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  Phillips #0 Screwdriver

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  Precision Utility Knife

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  iFixit Mandible Flush Cutters

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  Mako Driver Kit - 64 Precision Bits

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  Flathead 3/32" or 2.5 mm Screwdriver

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  Smart Wrench

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• 

  Nitrile Gloves 100 Box

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Background

W123 is the internal chassis-designation Mercedes-Benz used for their executive line of cars, manufactured between 1976 and 1985.

Within the W123 chassis, as it typical for Mercedes of the era, cars were named after their engine size, fuel type, and chassis sub-type.

Engine size was designated by its displacement in liters. So a 280E has a 2.8 liter inline-6 cylinder engine.

Fuel type was indicated by the trailing letter after the number. "D" stands for diesel. "E" stands for Einspritzung, which refers to fuel-injection on the gas engines. If there is no "E" or "D" then it is a carbureted gas engine.

Chassis sub-type is designated with another trailing letter after the number. "C" stands for coupe. "T" stands for touring, otherwise known as an estate or station-wagon. If there is no "T" or "C" then it is a 4-door sedan.

A few examples:

• A 240D is a 2.4 liter diesel engine sedan
• A 300TD is a 3.0 liter diesel engine station wagon
• A 200T is a 2.0 liter carbureted gas engine touring/station-wagon model that was not available in the U.S.

It's good to remember that "TD" does not stand for turbo diesel and instead designates the touring models. Turbo diesel models will have "TURBODIESEL" on the rear of the car, but there is no designation between turbo and non-turbo in the model numbers.

Early Diesel models offered in the United States, up to about 1981, were not equipped with turbochargers. Afterwards, the OM617 3.0 liter diesel engines in U.S. W123's were turbocharged (in other parts of the world a turbo charger remained an option). The OM616 2.4 liter diesel engines in the U.S. 240D remained naturally aspirated throughout their entire run. There were also several gas engines across the range. These various W123 chassis models shared many components but also have some distinct differences. Some guides will be specific to early Diesels, some to late. Others will cover all years and engine types.

The following models were available in the United States:

Gas version models:

• 230 (carborated 2.3 liter M115 I4)
• 280E (fuel-injected 2.8 liter M110 I6)
• 280CE (coupe model)

Diesel version models:

• 240D (2.4 liter OM616 I4)
• 300D (3.0 liter OM617 I5)
• 300CD (coupe model)
• 300TD (wagon model)

In the United States the larger engine cars, like the 300's, came with a long list of standard items that were options in other countries. They would come equipped with power windows, central locking, automatic climate control, and automatic transmission. Only the smaller engine cars, like the 240D, came with base-level features like manual windows and a manual transmission.

Author

with 5 other contributors

Nicolas Siemsen

Member since: 12/06/13

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79 Guides authored

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