Let’s be honest, owning a classic car isn’t always sunshine and roses. In fact, venture into the realm of automobiles over two decades old, and you’re stepping into a world distinctly different from modern vehicles. Cars from the pre-2000s, especially those clocking over 200,000 miles, often come with a unique set of challenges. Think deteriorated seals, elusive parts, and a general reluctance to run smoothly. Mechanical and electronic systems from past eras can test even the most seasoned mechanics. This reputation certainly precedes the lauded, and sometimes maligned, W123 Mercedes-Benz. And perhaps, paradoxically, it’s exactly what makes them so appealing.
The W123 Mercedes-Benz chassis holds a legendary status among car aficionados. Its timeless design, robust engine, refined interior, and overall sophisticated aura have cemented its place as a highly desirable German classic. These iconic German saloons, coupes, and wagons are celebrated for their enduring quality. However, like any vehicle of a certain age, they can present a significant undertaking for even the most dedicated DIY mechanic.
This brings us to my recent acquisition: a 1983 Benz 300d. For a long time, I’ve been captivated by the W123 chassis, and after an eight-month search, I finally found a 36-year-old specimen practically in my neighborhood. Despite its quirks and imperfections, it has already become my favorite car. Yes, I know, predictable for a classic car enthusiast.
Let’s delve into the specifics. The Benz 300D, part of the W123 Mercedes-Benz series, was produced from November 1975 to January 1986. During this period, Mercedes manufactured four-door saloons, five-door wagons, and two-door coupes, all built on the same robust unibody platform. Engine options ranged from efficient 2 and 3-liter diesels (turbocharged from 1980 onwards) to a powerful 2.8-liter gasoline inline-six. In its heyday, this was the epitome of executive luxury, costing around $70,000 in today’s currency. I managed to acquire mine for considerably less, primarily because it comes with a few… character-building opportunities.
The positives first: it’s painted in a cheerful, though faded, yellow; the engine feels strong with reasonable blowby; the interior and exterior are in decent shape with no accident history; and remarkably, rust is minimal, at least, from what I’ve observed so far.
However, as you might anticipate, the list of areas needing attention is somewhat more extensive.
Practically every seal and gasket in the drivetrain requires replacement. The oil stains beneath the car speak volumes. The previous owner, it seems, surrendered to the vacuum system’s complexities and leaks, resulting in temperamental door locks and a transmission that shifts with the subtlety of a heavy-duty truck. The turbocharger is crying out for a rebuild or replacement, evidenced by oily inlet tubes on the air cleaner and oil dripping from the outlet manifold onto the passenger-side motor mount. The differential is weeping gear oil, and the rear passenger-side CV boot has split at both ends. Hopefully, a complete axle replacement won’t be necessary, but time will tell. The brakes are dangerously worn. A concerning knock and rotational whirr emanate from the driver’s side front suspension, intensifying with steering lock – potentially a ball joint or wheel bearing issue. Investigation is needed. And, almost unbelievably, a broken seat spring has pierced through the driver’s seat, delivering unexpected discomfort, a sensation far less desirable than raw horsepower.
I am by no means a seasoned professional mechanic, especially when it comes to driveway projects. Weekend wrencher might even be a generous description. Yet, this car has ignited a passion in me. Perhaps it’s the undeniable presence of the Benz 300D, or the resilient charm of this faded yellow classic, that fuels my determination to restore it closer to its former glory. I’ve already invested time and resources in replacing fluids and filters, witnessing firsthand the dramatic impact clean fuel filters can have on a diesel engine. Initially, this nearly 3,500 lb German sedan struggled on inclines. Post new NAPA pre-filter and Mann main filter, it now pulls like a train. Small victories are indeed gratifying.
A significant vacuum issue, hindering manual gear changes in the four-speed automatic transmission, has been resolved. An original vacuum line to the valve cover switch was plugged with a deck screw. While such a fix might be overlooked for something like the EGR system, for a vacuum-controlled transmission, it’s critical. Shifting is still somewhat rough, but I believe a VCV adjustment and some attention to the Bowden cable might yield noticeable improvements.
Starting the Benz 300D is generally fine, although the initial start-up isn’t its forte. The first start of the day results in a low and uneven idle, likely remedied by a long-overdue valve adjustment. Additionally, the tachometer is non-functional – a common ailment in these models, potentially fixable with an amplifier hack or a costly replacement. Further exploration is required.
The remaining tasks are the typical replacements and repairs expected with a nearly 40-year-old vehicle. Some might argue I’ve chosen an elaborate and expensive way to expand my mechanical skills, and they might be right. But what better way to learn than by working on a stylish vintage Benz 300D that possesses both character and a touch of school bus charm? Wish me luck as the journey continues.
