12 volt wiring problem

First you said you had starter rebuilt and replaced the relay. I think this is you problem but lets go through how the systems work.

The thing that keeps throwing me is you said when key is in run not start as if you got a 3 position key like in a car and no starter button.

If I were to guess at your problem (and I often guess wrong) I would say you had a 4 wire tractor relay. The way this one works is when you turn on key power is sent to the relay small plug from the key. The power goes out the other small plug to the grounding starter plug on the trans. When you push the start button it sends the power to ground which engages the relay and makes the starter start. If you replaced this relay with one from a auto parts store there is your problem. The auto relay works by grounding through the relay case. All you need to do for this kind to start is put power to the small plug. The other small plug is to bypass a resistor in the ignition system.

So did I guess right.
Things we need to know.
Do you have a 3 or 4 wire relay?
Does your system use the starter button the trans; a starter button in the dash; or a start position in the key?
Where did you get your new relay from?
Did this problem start when you replaced the relay and had starter rebuilt?

Let us know what you come up with.

Rod