Power cable problem/question

[Rolland]

I purchased a Lincoln Precision 185 used a few months ago, it was used altho apparently not much at least according to the previous owner.
The problem, or perhaps the question is: the power cord has broken down apparently and shorts out when the cable crosses over its self, or lies on a piece of metal. Basicly like a sparkplug wire shorting out and arcing across. When it does it won't weld for crap. It took a while to figure out why as sometimes it would work fine and other times not at all. I bought a protective cover for it but it compounds the problem as it is attached with snaps.
So my question is, (after all that) is this a normal wear and tear problem with Tig welders? or do I need to address something else. I have ordered a new cable.