Thanks everyone; I like the engineering-style approach.
I’m going to take measurements of the old fan.
It turns out the 30A fuse has indeed blown as well. That fuse sits by itself in the front engine bay. The power cables leading to the fan are also scorched.
Yes, it happened during a slow-speed section of a rally.
We shut the Morgan off and waited for it to cool down. I lost the rally.


Greatings from germany, +8 1997 3,9 l blue