Every Mercedes-Benz has a series of drains in the body to allow water egress - water will accumulate in your car under normal conditions and whenever you wash your car. Even if your car is garaged the drains will still become blocked after a period of time with road grime, leaf litter and dirt/dust. Ensuring your body drains are clear will help prevent corrosion and mold/mildew. The attached PDF shows the location of the various body drains for common classic Mercedes-Benz models. Use compressed air, pipe cleaners or a flexible plastic rod to clear the drains, taking care not to scratch the area around the drains or expose any metal.