Re: 70HP Force Lower Unit white Oil
You have a smoking gun. Before you jump to confusions and start changing all the seals, replace the oil with fresh and replace the screws with gaskets this time. Run the engine a couple of times and check the oil again. If it remains clear, there is no need to re-seal the lower unit.
Milky oil is definitely a sign of water but no damage has probably been done: The oil has corrosion inhibitors.