Small Engine Troubleshooting Problems? Ask a Mechanic Now.
Most likely the input shaft seal is the leak, where the drive shaft from the tractor to the gear box attaches. It can also on the lower side of the gearbox , where the drive pulley is for the blades. The usual problem is the bearing has failed, letting the shaft move. If the oil is slung out from the pulley, then it is the lower seal. If it is close to he driveshaft, it is the input seal. Repair will be new bearings and new seals, unless it has already damaged the inner gears.
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