Thanks Rob. Unfortunately this is not the fuel pump fitted to the T16 ( I mitted to mention my vehicle in the post) . I will check with one of the "new" V8 suppliers and ask whether they do a diaphragm for a T16 pump, it woudl certianly be the best way forward. I just wondered what everyone else does. Maybe there arent that many running Carriers on the forum!
It has certainly been my experience that old material will turn to goo pretty quickly once petrol hits it, and of course this coudl endanger the engine if the fuel drains down into the sump diluting the oil. So you have a double worry with old diaphragms ( nothing changes in life does it?)