Welcome to Cosworth ownership, I should of done my usual message, what you are seeing there is the cooling fan fuse, the wiring loom for which was sub standard when new!

You need to rewire the fans direct from the battery, you can buy looms to do so, NYRS and MSD to name a couple, the former also will supply you with a fan switch connector, if you don't want to DIY, if you do a search on here there are plenty of wiring diagrams!

It's also worth fitting an "uprated" switch, as the span of the OE one is the problem part, as the fans come on to early and stay on for to long, which is what leads to the fuse melting!

This and the fuel pump wiring are two chronic weak points on these cars, this suffers with a similar issue whereby the old wiring builds resistance and so the pump cannot draw the power it needs under load, i.e. when giving it a bootful, this can cause an engine meltdown! Again a loom to rewire direct from the battery is the remedy!

You want to get the fans sorted as at the moment they won't be working, unless someone has already rewired of course?

Also change the cam belt, unless you can be sure it has been done recently.

Martin