Yeah your right grumpy, the recent attempts to fix this problem have resulted in immediate leaks whereas with the first and only successful replacement it was several years before leakage was again evident. I,m guessing then your other observation of it being a non standar size is most likely to be the case, although with this last disarster some damage is noticeable now that I have removed the part from the tank. It seems the only replacement parts for this model are aftermarket so may not be true to specification, but what I intend to do is buy another assembly and fit it myself using perhaps a light machine oil to lubricate the grommet first.
Thanks for all you advice, it's always helpful to get other ideas and tips, especially from someone that has "been there, done that".
Cheers
Bob
