as the fan is a heavy load (even after the relay)the draw of current is causing the weakest link to get hot (point of less resistance..i.e fuse and holder)..
blade fuses are fine for low draw positions lights horn ect.but high draw components require somthing larger..
example.open the bonnet on a modern car look in the fusebox near the battery the fuses will be huge in size but not always in amps..
so the contact area in the holder is larger eliminating the heat build up at the point of contact
i.e the holder.
so back to kev's bothers 4track same amp fuse but of a phisically larger size and better contact areas (bolt in)...see simples..
class dismised..
tony
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