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Water damage

How long does it take for water to damage an engine? I recently purchased a car and after 31 days the engine locked and the mechanic is saying it was because of water damage. I have not driven in a flood or high water although I did have my vehicle splashed with a lot of water while driving. He said the air filter is wet and there was water in the oil pan as well as pieces of blown piston. This seems weird to me so please help. My insurance is paying to replace the motor but it just seems unlikely to me. Tell me what you think?


  • edited May 2010
    What it sounds like to me is, you had a blown head gasket. The coolant got into at least one cylinder, and this caused the piston to blow. air will compress on the compression stroke, but coolant will not, and the pressure has to go somewhere. once the piston was blown, the coolant went into the pan, and was circulated with the oil and piston parts. In addition, the head gasket was further damaged, and if valves were also damaged which is likely, coolant and or oil could well have been blown back through the intake manifold and up the carburator (if it is a carburated engine) or if a fuel injector was blown out too, into the air intake filter. Once an engine starts to come apart when running at speed, there can be a long train of damage such as you describe.
  • Ignoramus posted a very plausible possibility.

    Another is that you somehow got water into the air intake is sufficient volume to be drawn into a cylinder as fluid, the insbility of the water to compress caused the piston's connecting rod (or wrist pin) to break freeing the piston and connecting rod parts to fall down the hole to the spinning crank like silverware into a garbage disposal, and the damage compounded.

    Usually this takes driving through high water to happen, but your comment leaves the imagination to wander.
  • edited May 2010
    It's quite possible for an engine to be destroyed by rain water or engine coolant if it is pulled through the intake and causes a hydrolock situation.

    Since the air filter is wet and the engine is obviously trashed this means that you must have driven through one puddle that was just a tad too deep. It doesn't have to be a flood to cause this.
    You're amazingly lucky that an insurance company is paying for this.
  • edited May 2010
    Even it was water how quickly can water damage am engine? What I'm thinking is that If it the insurance could have pinned on the dealership from where I bought it about thirty days ago they would have so that they wouldn't have to pay for the replacement motor.
  • edited May 2010
    If an engine takes in big gulp of water, then it will be instantly damaged (as in less than one second). As soon as a cylinder fills with water and begins its compression stroke, it's all over. This is known as hydolock. Look it up on the web.

  • Tardis is absolutely correct as always. The damage that we're describing in detail in reality happens instantly. Remember that if your engine is turning at 2,000 rpm when the cylinder hydrolocks, each piston is going up in its compression stroke roughly 16 times every second. The damage is immediate.
  • edited May 2010
    My wife was driving and left a parking lot and there was no rain or puddles and the car stopped about two miles from where she left. I'm just confused about how the water got there. Is it too crazy to think that the I bought the car with water damage. Then again I would think the car insurance investigation could have brought this out and they would pin it on the car dealership. Btw thanks to all for the replies.
  • edited May 2010
    Now that more of this story is coming out could you fill in all of the details? This is starting to put a different slant on things and knowing the details would have possibly steered any advice off in a different direction.

    So does this mean the car was at the dealer for service? If so, what kind of service?
    Any engine repairs other than normal maintenance?
    Any symptoms before it made a bang and quit?
    And is this vehicle back at the dealer or is it somewhere else?
  • edited May 2010
    I took it to my dealer and they sent it to the manufacter at another dealership. This is where they said there was water damage and where te car insurance claim adjuster did his investigation. My wife was driving it and said that it suddenly had problems and shut down. She drove it about 18 miles to work and it shut down about one and half miles from her parking lot.
    Since the car couldn't turn over i put the key in the ignition we checked the battery and starter and so off so we towed it to the dealer. We just bought it so no maintenance had been sone other than the standard check by the dealer before a used car is sold. Also the car dealership claimed the car had 10 quarts of oil but the mechanic and the claim adjuster said it didn't cause the damage that the water did.
  • edited May 2010
    how quickly can water damage an engine?
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