Have currently removed my engine to repair the transmission => by the way, removed timing belt cladding to check the condition of the timing belt. As far as possible, only the deflector roller looks a bit damaged. Can one exchange the individually without relaxing or touching the timing belt? Have still the gas pressure tensioner, not the mechanical one. In theory, one would have to leave the belt tensioned, otherwise the gas pressure damper adjusts massively – to the back he would have to press out … PS: is a BF5252S engine, BJ ́93.