John makes several good points. But I would also add that you are likely to spoil your oil job if you were subsequently obliged to take the clock to pieces for an adjustment. Depending on the clock, things like the clutch (cannon pinion) on the center wheel of a German clock, or the minute pinion (center) shaft clutch on an American clock should be lubed while apart. Springs as well. The rest of it should be oiled when you know you are finished with the repair.