Hi Scott,
Many thanks for the response. I had a gut feeling that the starter was press fitted as it would not turn in any direction by hand. Did not use any tools and was waiting to see if somebody comes up with this reply.
Scott, would you think Carlos be needing the whole turbine or just the starting bit to make the alteration? Somebody had told me that the front cover needs to be replaced when changing the front starter. I do not know if this is so in such cases.
There is a very slight vibration when idle but at the rpm (about 90k) when the cone starts coming out there is no vibration at all. That is why I was thinking that it must be the air pressure that is drawing the cone towards the hub. I was thinking on the lines that there is some sort of spring inside the starter that drawings back the cone after the turbine has started to spool up.
Anyway...many thanks...interesting reply

Reuben