86' Starter problems (electrical)
 

I recently was given a 1986 Rx7 GSL to restore, and have as a project car. After diagnosing several electrical circuits, I found out that I needed to replace the Clutch switch, and also that the starter would not engage with the key. I ran several tests on the starter to see if it worked at all, and it does if I hook a + wire to the battery, and a - ground, but I could not make it work through the key. I tried several things, and finally when I ran a new ground wire from the starter directly to the frame, the starter turns using the key now. The problem I am having is this, I have tried everything from 16 gauge wire all the way up to 10 guage wire for the negative ground wire. Within 3-4 seconds of cranking the starter, the wire melts through the plastic coating, and then burns through. I have tried installing a fuse on the negative wire with similar results, except just the fuse is burnt. I cannot find any information on what would cause this, or how to fix the situation. I thought of doing like a race car, and running a bush button switch directly from the battery to the starter, but I am trying to keep as mush as possible to normal starting procedure. does anyone have any ideas or comments that can assist me? Has anyone else has a problem such as this?

Josh

ANyone???
 

I really could use some help please....