TIDYING UP
Grant continues to eke out the potential of his SLK by re-painting the stiffening bars and the cabin’s soft-touch surfaces 1999 MERCEDES-BENZ 230SLK
The R170 SLK does not enjoy the finest reputation for rust resistance; certain areas suffer if neglected, including the unique chassis stiffening bars or subframe connectors. These run from the front and rear portions to the central sections to reduce flex. It was while replacing the fuel pump ( CCW, 10 March) that the poor condition of the offside rear strut became clear.
All four bars secure to the floor alongside the sill panels at one end and travel diagonally to the centre with the front attaching just behind the engine, while the rear locates inside the forward edge of the spare wheel well. Rear bars vary slightly in length but the fronts are identical and 12 M10 Torx bolts secure them.
After much research, I felt quite confident armed with a large breaker bar; the screw threads came from the factory wrapped in Loctite and don’t give way without a fight. Advice from SLK World explained that Mercedes dealers could supply four new bars with fittings for around £100 and although this sounded tempting, I thought it best to assess the condition of my 22year old examples first.
Extra care must be taken when locating the Torx bit; if it’s seated incorrectly one slip could ruin the M10 bolt, with the consequences of extra time and money expended. In the past, a liberal helping of black paint had been lavished on our stiffening bars, too, so this had to be picked out of certain M10s. Once cracked free, I gave the bolts a good clean with a wire wheel and paint-removing poly discs shed old coatings in no time without damaging the metal.
Surface rust had run riot in some areas but overall, the original units could go another decade, especially after two primer coats and several applications of Rust- Oleum grey – the colour chosen to blend into the background. Re-fitting was much easier, fresh Loctite and bolts ‘nipped up’, but not over-tightly, should ensure that they stay put.
On to the next job; sorting the peeling soft-touch surfaces in the cabin. Peeling interior trim paint is a common issue with all SLKs because Mercedes chose a rubberised covering on trim panels from the 1990s that comes apart. Many describe it as latex but whatever it is, areas of high usage such as the centre console, door handles and so on peel and the black areas beneath show through.
Options are plentiful but most involve stripping out the interior, but while my peeling trims are limited to the driver’s door handle and centre console, that seemed excessive. One UK based company will carry out a complete re-finish of every panel and seats, but that wasn’t compatible with my budget.
Chatroom conversations led me to a German product called Volico that was originally supplied in a small pot to apply yourself with a sponge. My vehicle data card listed the trim paint code, also known as Mondrianblau, which cross-checked with the website for a 150ml spray can; unfortunately, that is the only dispenser now available for the R170 SLK.
One important detail that came courtesy of forum videos explained that this product will only adhere to a clean surface and that anything stronger than soapy water will remove more of the original coating. Once the surfaces were clean, I sprayed some Volico into a pot and nervously checked for match with a small kitchen sponge. It was almost exact, so I dabbed a first coat across the areas showing black, then applied a second coating right across the trim once it was dry, trusting the sponge on both occasions.
The covering lost its sheen overnight and blended in well, so once again, advice from other owners came up trumps and my SLK has a spot-free cabin once more.
Question is – what little jobs should I tackle next?