GE refrigerator compressor/fan wont restart once it cuts off. pls help.

My refrigeratror wont cool once the compressor cuts off.
here is what I know about what it does/doesnt do.
works great on both the cool and freezer side while the compressor is running.
then the compressor and condensor fan cut off and will not come back on at all.
I have to cycle the freezer thermostat all the way to zero and then back on. at that point, I hear a relay in the main control board come on, but nothing alse. meanwhile, the fan in the evaporator is allways running. I dont know if that means anything. if I cycle the thermostat on and off a couple of times the compressor/fan finally come on and everything works great untill some hours later and we are back to the beganing. The only thing I have replaced is the overload relay that attaches to the compressor because it was melted. I am not sure if the overheating was caused by something not turning the compressor off at the appropriate time or not. I do have some multimeter and have in the past worked as an electronics tech on some gear, but I know not much about refrigerators and without a schematic diagram, I am lost. any pointers on what to check and what I should look for. can locate any part but am not sure what I should look for. pls help. thanks epi