Motor oil contaminated with water can damage your auto's engine. Luckily, water and oil naturally separate. When contained together, water settles to the bottom while oil rests on top. Dirty motor oil may settle to the bottom because of the increased weight of metal particles. If you have dirty motor oil with water, take the oil to a recycling center. However, clean motor oil contaminated with water may prove useful following clarification. Use the basic physical principles of oil in water to remove the water and end up with useful motor oil.
Poke a few holes in a 2-liter bottle cap with a pushpin.
Pour the contaminated motor oil into the 2-liter bottle and twist the cap on securely.
Turn the 2-liter bottle upside-down over a refuse bucket.
Poke a few holes in the bottom of the 2-liter bottle to allow airflow into the bottle.
Allow gravity to pull the water downward and out of the bottle cap. Collect the water in the refuse bucket. When all water drains out and oil begins to leak from the bottle, pour the oil into a separate and clean container for motor use.