Mercedes C300 Convertible Hood Refurbishment

This Mercedes C300 Convertible came in for a hood clean, reproof and super-wax protective coating, plus Krytox rubber treatment and a drain flush. Gary walks through what he found before starting and why each part of the job matters.

What the roof showed before we started

The most obvious marks were zigzag lines running across the fabric. These come from jet-washing -- the nozzle moves across the surface and if it is too close it removes dirt but also disturbs the fabric weave, leaving those tracks. Most of them were expected to clean up; one area was slightly deeper but still within what a good clean and coating would settle down.

Fold lines were visible at the crease points. Gary notes these appear on a brand new roof within a week or two of use; they are normal and not something a clean removes. There was one weak area at a fold where, if left with grit sitting in the crease, the fabric would eventually have worn through. Caught at this stage, the clean removes the grit and the coating protects it; left another five years it would have needed a new roof.

The rubbers felt crusty to the touch. There were also chemical marks on the chrome and coated-aluminium trim -- the result of strong chemicals used in automatic car washes. Those chemicals bleach chrome and also strip any wax from the paintwork; Gary notes that ceramic or graphene coatings resist them, but this car had neither, so the damage had already been done. The marks were polished back as far as possible with a metal polish product.

Why the rubbers and drains matter

This Mercedes has three roof drains. People assume a convertible leak comes from the roof itself; Gary says it is invariably the rubbers or the drains. Rubbers perish and let water past; blocked drains send water down inside the A-pillar and fill the foam under the carpet before you notice anything. By the time your feet are wet you likely have 5 to 20 litres under the carpet. All three drains were flushed clear; all the rubbers were treated with Krytox.

The result

Hood clean, reproof and super-wax coating applied. Gary's description after: feels like a brand new roof -- nice and fluffy, not stiff. The weak fold area is no longer a concern now the grit is out and the coating is protecting it. A new hood on this car would be around £2,000; a clean and reproof every couple of years means the roof should last as long as the car. The customer was given a printed invoice as a service record to keep with the car's history.

See our convertible roof cleaning and restoration page for the full clean and reproof service, and cabriolet hood protection for coating options.