cheers for the feed back. 1st up when i changed the bearings they were'nt scored or coppered i changed them as a precaution just to make sure it was'nt them it baffled me at the time.
yes mate it was the radiator that had cracked which i found out when i'd got home and it does make the noise all of the time upto around 3500rpm then i think the tapping dies off or i just cant hear it . when i had it on the rollers lee at power engineering said it sounded fine under load and did'nt know what the noise was and its definately in the bottom end.