Wet Weather and Engine Damage

The recent rain storms in the southeast have been causing drivers a lot of trouble.  In addition to the flooding, the rain has been causing vehicle engines to stall.  It’s easy to see how water might be getting into engines and causing damage to pistons, rods, crankshafts, and bearings.  When such a claim is encountered, one of the first things to be done is to obtain an oil sample.  When water mixes with oil, the tendency is for the water to separate from the oil.  Water is naturally heavier.  Its density is 62.4 pounds per cubic foot.  Motor oil, on the other hand, has a density of approximately 55 pounds per cubic foot (depending on the weight of the oil).  After the sample has been obtained, if the oil appears to fill the entire occupied space, then no water most likely entered the engine.  However, if the oil appears to be “floating”, then water has most likely entered the engine.  Examples of oil in both states are shown below.

Uncontaminated motor oil sample

 

Motor oil suspended in water

WARNING:  if you know that your engine is about to fail and you are going to have to pay for a new engine, don’t try pouring water into the engine and claiming to your insurance carrier that it was flooded.  First, a wear metals analysis will indicate the condition of your engine.  Second, the vehicle better have been in a flood and even then, the entry point of the water into the engine will have to be established.  Third, the damage to the engine has to be consistent with that caused by water.