I have 1979 F150 with a 351 Windsor and I can't figure out my electrical problem. when you turn the key to the on position the starter motor wants to spin the engine over.

 

Starter solenoid contacts stuck closed?

Richard

 

Done further testing and found that the there is like a short to hot side in the electrical. There is constant power to the red blue wire ( ignition to solinoid) untill you touch a test light to that wire then you hear a click from the coil. then it will work until you try to turn the engine over then it is like it is shortin it self out on the hot side