The oil pump is turned by a vertical shaft that is geared from the governor. The shaft is in two parts with a coupling connecting the two. The coupling is made of cast iron so that IT will BREAK (like this one did) if, for any reason, the oil pump cannot turn. The oil pump is located in the lowest part of the crankcase. If there is any water in the oil, and it has frozen, THAT is where the ice will be. That is probably what has happened; the oil pump was frozen stuck.|
You need to unbolt it from the bottom of the tractor. (It is the circular plate with three bolts in it, right in front of the oil drain plug). Be sure to find BOTH broken pieces of the coupling. Get a new coupling from STEINER TRACTOR PARTS, and slide the pump back into place.