7.3 power stroke diesel glow plug control relay question?

I have a 97 f250 and I had a bad glow plug relay. A farm mechanic put an alligator clip on 2 sides of the relay and it runs, but I have to take the clip off to kill the motor. I changed the relay, but it still wouldn't run without the clip. I thought I got a bad relay so I got another one, and tried again with the same results. Anyone have any ideas?