I have jd 2350. The temp gauge is acting up. I have replaced the thermostat, sending unit, checked wiring. It will still measure hot with minutes of starting the tractor under no load. You can tap gauge cluster and the needle will jump to normal and then back to hot in a few minutes. Even when hot you can touch the coolant hoses with bare hands. Any suggestions? I was wanting to put a new gauge but it is part of the entire console. Can i just use an aftermarket gauge and the current sending unit?