Peter I had the same problem, a puddle on the floor and drops at the bottom of the radiator.
First thought was the hose which was also wet.
But my experience of 45 years as a plumber has taught me to always start looking at the highest point.
And there it was!
[Linked Image]

The O-ring at the nipple to de expansion tank.
[Linked Image]

Couldn't see that without removing the cowl.
[Linked Image]

Here you can see how I fixed it.
http://www.talkmorgan.com/ubbthreads.php/topics/726299/re-radiator-leaking#Post726299


Paul

1990 4/4 1.6 Ford CVH Sold
2014 +4 2.0 Ford
2005 BMW Z4 2.2 6Cyl Sold