I was wondering if anyone could help. We have driven our w124 e280 estate 1995 from the uk to the centre of France (Loire valley, Sancerre). The last couple of days when we have returned from a drive the coolant overflows and the temperature gets to above 90, but when we're driving around the temperature seems fine, around 85-90. The car was checked by a local garage and they couldn't see any obvious issues i.e. Worn pipes or worn radiator cap. On Saturday we're planning on driving just north of Paris and then onto Dunkirk to take the ferry across on Tuesday. Is it safe to drive the car and fill up with water when needed or would it be better to call the RAC breakdown before driving any further?