Im I ok to just remove the tensioner and replace that washer? I remember doing my M3 and it was just a case of unscrewing changing the washer then tightening it back up? is that the case with the TD5 also?
yes but the chain tensioner has nothing to do with what you posted IMO, cos it's under the front cover and it can't cause any leak, you must remove the front cover to reach the chain tensioner
If I remember right the big nut arrowed is a spring loaded bolt which has a sealing washer. It pushes against the plastic chain guide.
You can unscrew it and change washer
sorry, for me the accuracy of terms is problematic... i edited my previous post, the fact is that the ''chain tensioner'' is not = hydraulic adjuster to me