Restoring a Mercedes 190SL Step by Step

The Mercedes 190SL is one of the most iconic roadsters of the 1950s and early 1960s. With its sleek design, durable engineering, and legendary pedigree, it’s no wonder collectors and enthusiasts dream of owning one. But for many, the real joy comes from the journey — restoring a Mercedes 190SL back to its former glory.

If you’re considering this ambitious yet rewarding project, this step-by-step guide will help you understand what’s involved and how to approach the process with precision and care to ensure restoring a Mercedes 190SL is not only fun but done right.

Step 1: Initial Assessment

Before diving into tools and parts for the Mercedes 190SL, the first step in restoring a Mercedes 190SL is to conduct a thorough evaluation of the vehicle’s condition.

• Check for rust, especially in the undercarriage, floor pans, rockers, and wheel wells.

• Inspect the frame to ensure it’s straight and has no structural damage.

• Document everything, including missing parts, areas of damage, and modifications done by previous owners.

This stage sets the tone for the rest of the project and helps you determine the time, cost, and scope of the restoration.

Step 2: Disassembly

Once the car’s condition is documented, the next step is a careful and organized disassembly.

• Label every part and bag all hardware — future you will thank you.

• Take photos at every step to use as references during reassembly.

• Store parts safely in labeled bins or containers.

The disassembly process should be meticulous, especially for a car with intricate details like the 190SL. Rushing here can result in lost or damaged components.

Step 3: Body and Frame Restoration

Restoring a Mercedes 190SL often involves extensive bodywork, especially if the car was exposed to the elements.

• Sandblast or media-blast the frame and panels to remove rust and old paint.

• Weld new metal into place where needed, focusing on structural integrity.

• Use lead or body filler sparingly to smooth panels without compromising strength.

• Prime and seal the bare metal to prevent new rust before painting.

This is the perfect time to correct body panel alignment and ensure proper gaps — things that become much harder to fix once the car is painted. Aesthetically, this step in restoring a Mercedes 190SL is essential.

Step 4: Engine and Drivetrain Rebuild

The 190SL came with a 1.9-liter inline-four engine and a four-speed manual gearbox. Rebuilding the powertrain is a critical part of restoring a Mercedes 190SL to original factory standards.

• Disassemble the engine and inspect all internal components.

• Machine and hone cylinders, and replace worn pistons, bearings, and gaskets.

• Rebuild or replace the carburetors — the original Solex units are tricky but period-correct.

• Inspect the transmission for wear, especially in synchros and gears.

• Restore the differential and driveshaft to factory spec.

Take time to source OEM parts or quality aftermarket components. If you want a concours-level restoration, originality is key.

Step 5: Suspension and Brakes

Handling and safety are often overlooked during restoration, but they’re essential to the driving experience.

• Replace bushings, ball joints, and tie rods to tighten up the suspension.

• Restore or replace shocks and springs with period-correct equivalents.

• Rebuild brake calipers and replace lines and pads for safe stopping power.

• Inspect and recondition wheel bearings and hubs.

During this stage, you can also refinish the suspension components with factory-correct coatings or powder coat them for durability.

Step 6: Electrical and Wiring

Electrical systems in classic Mercedes are relatively simple but still require attention.

• Replace the wiring harness if it’s brittle, frayed, or has been modified.

• Rebuild the original gauges or find suitable replacements.

• Test and restore lights, switches, and relays.

• Install a correct 6V or 12V battery depending on how original you want the build to be.

This is also a good opportunity to upgrade for safety, such as fusing circuits or adding a discreet cut-off switch.

Step 7: Interior Restoration

The interior is where the driver connects with the car, so attention to detail pays off.

• Restore the dash and instruments, making sure all switches and knobs are correct.

• Install new seat foam and 190SL leather covers using factory patterns.

• Refinish or replace door panels, carpets, and trim.

• Recondition the steering wheel and gear knob, ideally using original materials.

If you’re restoring a Mercedes 190SL to factory specs, research factory-correct materials and color codes to maintain authenticity.

Step 8: Paint and Final Finish

Now comes one of the most exciting steps — bringing back that showroom shine.

• Choose a period-correct color, or repaint in the car’s original hue using its data plate.

• Prep the body meticulously, including blocking, sanding, and priming.

• Apply high-quality paint and clear coat, then polish to a mirror finish.

• Ceramic coating or wax can add protection and depth to the finish.

Be sure to paint small components like mirror bases, grille inserts, and door jambs separately to avoid overspray and detail loss. This step in the cosmetics of restoring a Mercedes 190SL is very important and if not done right will make your beauty not so beautiful.

Step 9: Reassembly

This is where the project comes full circle. With all the parts restored or replaced, it’s time to put everything back together.

• Use your reference photos to ensure proper fit and orientation.

• Install glass and seals carefully to prevent leaks or misalignment.

• Reconnect the wiring harness, testing systems as you go.

• Fit the chrome trim, bumpers, emblems, and accessories.

• Mount wheels and align suspension for proper stance and handling.

This is a time-consuming stage but incredibly rewarding. Take your time and don’t rush — the details matter.

Step 10: Final Testing and Road Tuning

Before you can confidently take your car on the open road, it needs to be tested.

• Perform a complete systems check — brakes, lights, engine temps, and electrical.

• Tune the carburetors and ignition for optimal performance.

• Take short test drives, noting any noises, leaks, or performance issues.

• Make adjustments as needed and perform a final detail.

Congratulations! You’ve completed the incredible journey of restoring a Mercedes 190SL. Now it’s time to enjoy the ride.

Final Thoughts

Restoring a Mercedes 190SL is more than a mechanical project — it’s a tribute to history, design, and engineering. Whether you’re doing it yourself or coordinating with specialists, every step you take brings new life to a classic that deserves the road once again.

If you’re patient, meticulous, and passionate, the reward is more than just a beautiful car — it’s the pride of preserving a masterpiece.