Oilers/Plant Tenders (HHC) Civil Service Practice Exam

A possible indication of water contamination in engine oil could include?

1. Increased engine temperature

2. Foaming of the oil

3. Lower than normal oil pressure

4. Strange noises from the engine

The correct answer is: Foaming of the oil

Foaming of the oil is a significant indication of water contamination in engine oil. When water gets mixed with engine oil, it can create an emulsion, leading to the formation of foam. This foaming can reduce the effectiveness of the oil, hinder its ability to lubricate properly, and impair the oil's overall performance. If foaming occurs, it may result in poor lubrication, increased wear, and eventual engine damage if not addressed promptly. Increased engine temperature, lower than normal oil pressure, and strange noises from the engine can also indicate engine problems, but they are not definitive signs of water contamination. For instance, increased engine temperature might be caused by issues such as inadequate cooling or poor engine performance. Similarly, lower oil pressure could stem from a leak or a failing oil pump, rather than directly indicating water in the oil. Strange noises may result from a variety of mechanical issues unrelated to the presence of water in the oil. Therefore, while these symptoms could suggest problems within the engine, foaming specifically points to the possibility of contamination from water.