My wife owns a 2003 Mercedes-Benz SLK, which we bought about three years ago. Since we owned the car, it has only covered about 3000 miles a year and is serviced once a year by an independent Mercedes specialist. At the last two annual services, we were advised that there was a small oil leak from the timing chain casing. We were told it was a common fault and could be rectified by a 'simple conversion'. We are not familiar with this so-called 'conversion'. Will you be able to elaborate/clarify this for us please?