Tractor Repair: Case MX110 Shifting Problems, shifting gears, pressure switches

Question
I've got a Case International MX110 that wont shift. It might start shifting gears fine when its first started, but it soon stays in gear or will shift from first to fourth. All you have to do is turn it off and its fine for a unknown amount of time. I have had it in the shop twice and they cant figure it out. Any help would great. Thanks

Answer
Sounds to me that you have a pressure switch with a problem. On the shift valve there are two pressure switches one for 1-4 and one for 2-3. If you have a switch bad saying that there is pressure when it's not there then it won't shift. My advise change the pressure switches  and swap the solenoids. Or you can check them. With the key off disconnect the pressure switch and connect a ohm meter and check to see if there is continuity between the two terminals. Check this when and when you are not having the problem. Clean all of the tractors grounds 90% of intermittent electrical problems are ground related. Start there, if you have any other questions  feel free to follow-up.