Ford F-100 Starter Relay sticking (on third exchange?)

[hondadad2622]

This started with an issue with setting my points. I was arcing from the positive post on the relay on the wall to the starter post to get the distributor to a high point so I can set my points.

I have over a three week period changed the cable from the relay to the starter. I did use a bigger gauge because Advance Auto did not have the cable I needed. I have had a constant issue with every time I connect the battery my truck engine starts turning over without even the key in the ignition. I have discharged the battery twice trying to find the problem. I cannot turn off the starting unless I pull a cable off the battery!

I have also exchanged the relay twice. The same mystery engine starting started again when I connected the last relay to the battery.

I have had relays stick on this truck over the years but never had it go through three.

Suggestions? I have checked the ground cable to the block and it is on tight. It is an older cable, would changing it help for any reason?

Would the larger gauge of cable to the starter have caused this? I had a good running truck until I started arcing on the first relay. I was just trying to tune my truck.

Help!

Thanks for all of your help! Great forum!