[Razorback1980]

Ok...so put that same voltmeter on the smaller connector of the starter and see if you have 12V while cranking there. If you do not have 12 V there, then look to the switch key.

The way it works is you should have 12V on the starter from the battery and there is a wire that runs from there to the switch key and the switch key goes back to the small terminal on the solenoid. When you hit start on the switch key, it sends 12 V back to the small post on the solenoid which sends 12 V to the starter motor and the starter turns. So if you have a full 12V at the big post on the starter but don't have 12V on the little post when you turn the key to start, the switch key is probably the problem. If you don't have a full 12V at the big post on the starter, look back toward battery cables.