The oil pump drive gears are built into the front oil pump aluminum housing which bolts to the front of the motor and to the front of the oil pan. There are no hoses that can leak. The only sealing surfaces are the gasket between the cast-iron block in the aluminum housing and the crankshaft seal itself. This gasket is not known to leak although with the mileage that you have it's hard to say. More than likely what you'll find is that the crank seal which is behind the drive gear for the timing belt is probably bad. Normally just replacing this crank seal will take care of your oil leak. There is a possibility that you also need cam shaft seals. If the gasket between the oil pump housing is leaking you will need to remove the oil pan in order to remove the front oil pump housing assembly to replace this gasket.
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