GM-GMC: starter problems, gm diesels, starter solenoid

Question
I have a snowcat the year is a 1969. I turned the key on and all accessories worked then I turned the key to start but the solenoid clicked once and then all was dead like a dead battery. The solenoid has cable from the starter to the solenoid and then from the solenoid to the battery. In a few minutes it seemed to reset itself and all accessories worked again. I could then turn the key to start again but it would click once and everything would just be dead again. I changed to a fully charged battery and cleaned the cables. Tried again same deal. I then changed the starter solenoid same deal one click and all dead. As soon as I would remove the cable going from the battery to the solenoid it would then allow me to immediately turn the key to start again but still only a click. I could also feel the click in a part called the electronic regulator which I assume is the voltage regulator?. After several of these attempts it got past the one click and it worked and started the engine. Now it seems to work just like it should. It is up in the mountains so I have to be my own mechanic. I need some help with this one.
Would this be a dead spot on the starter or what would be the problem, could it be that voltage regulator? The starter always works great before never any problem I put a new one on it when I bought it a couple of years ago and it doesn't get that much use. The starter is in a very hard place to get at or I would simply replace it so I wanted to know before trying to do that. I sure hope you can tell me. Thanks so much. Rich  

Answer
This is quite distant from GM diesels, but I will try to help.

Yes, you could have a dead spot on the starter.  You could also have battery cables that have corroded, under their insulation, and are producing too much resistance for current to flow to the starter.

Given your description of the hard-to-reach starter, I would replace all of the battery cables, including the ground cable(s), before removing the starter.