Anyone with one of these units that could help me...

I have had it on my bench for several months and finally got around to
setting it up last week.

My question relates to a long tapered coil/spring that was inside the
welding tip. When fully extended this spring would poke outside the
shield by about 4 inches. This just looked plain wrong and was not
evident in any of the instructional diagrams that came with the unit.
Further, pushing back on it would slide it back into the tip/sleeve so
it was not fixed. On top of that it seemed to interfere with the
feeding of the weld wire.

I noticed that is was flared at the tip end to prevent it from slipping
out of the screw on tip, so it seems an integral part of the unit.

I left it in and have since fried it completely; my first attempt at
welding heated it sufficiently to make it deform.

My question: throw it away or try and replace. What the heck is that
thing for?

Thanks,
Bryan