If there is water in the crankcase, how would the oil appear?

When water enters the crankcase, it can mix with the engine oil, leading to a significant change in the oil's texture and appearance. The presence of water causes the oil to become thick and frothy because the water does not blend well with oil, which leads to emulsion formation. This emulsion results in a bubbly or frothy consistency, showing that the oil is no longer functioning effectively.

Thick and frothy oil would indicate contamination and can also suggest that the engine's lubrication system is compromised, potentially leading to serious mechanical issues if not addressed. This transformation hints at ongoing wear and tear, highlighting the importance of maintaining clear, uncontaminated oil for optimal engine performance.