Battery terminal overheating

Hi

My positive battery terminal is overheating, it got red hot and the cable housing started to smoke….
any ideas? The car has been sitting for a few years and I've only recently got a new battery to get it back on the road
dodgy battery maybe? I didn't tighten the clamp just pushed it on, would that affect it?
I didn't notice it overheating the first few times I fired it up, just today!

Any help much appreciated

Kev

if it does it just sat, your battery cable is probably shorting to earth. trace it to see where if so. it should run from battery to starter 13mm nutstud, then from starter to alternator. if its an early one there should be 2 lives from alternator straight to battery, plus the wire from battery to starter stud