My father has a John Deere 110 that is 2 years old and only has about 85 hrs on it that is not starting. Every so often it will start when cold but will not restart once warm. When you turn the key the motor will make maybe a 1/4 turn and then freezes and you hear a loud whine from the starter area as if it has met resistance and the motor wont turn. He replaced the battery and fuel with no change. We checked the voltage at the starter and its only receiving 5-8volts the solenoid was replaced but no change. I have tapped on the starter much how you can do with a car just to see if its stuck with no luck. So basically tried all the simple fixes so far and don't see any point in replacing the starter since it appears its a voltage issue. Any tips on what to check that might be causing this? thanks in advance