I just popped out and so did some of the water from the header tank. Went about 1/2 mile and stopped at some light and whisps of steam appeared whilst the engine cut out, let it cool and refilled header bottle, pumped rad pipes to get rid of any air, started and ran but haven't got time/space to investigate/repair. Have a couple of photos but a few more later. Has a drivers side dent/scratch. Located on a road in Godalming Surrey.