JD 310SG Backhoe

I have a JD 310SG, that is acting weird. It is showing hot on the emp. gauge, but is not running hot. It shows a code of F450. When started cold, it runs for just a few minutes, then the needle starts to rise. It climbs to the hot side, and shows F450. When disconnected, the needle stays on the cold side, and when connected, it seems to climb with the more RPM's, until it pegs out and shows the code of F450. I have changed the water sending sensor, the operating solenoid in the dash. I have...

JD 310SG Backhoe

JD 310SG Backhoe