Are you sure of that model number? I have a 2140 which has the gear transmission and they also made a 2145 which was the same tractor except it was a hydrostat transmission. Both of these had a 14 hp Onan engine. I have never heard of a 2146. Does yours have the Onan engine?
You need to remove the oil pressure light sending unit and replace it with an oil pressure gauge. Start the engine and see if pressure registers on the gauge. If it does, your sending unit is probably bad. If there is no oil pressure, you're going to have to pull the cover off the end of the engine that has the electric clutch and see what's wrong with the oil pump.
