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Water in oil compartment

What happens when you put 8 cups of water in your car’s oil compartment? What happens if you drive about ten miles on it?

I read where right after WW II, Andy Granatelli had a car in the Indianapois 500 race. The rules prohibited adding more oil and his car was low on oil. He added water to the crankcase theorizing that the remaining oil would float up to the top and he could go a few more miles. As I remember the story, he did get more laps before the engine blew. I think you have added equivalent of 2 quarts. If the car still runs, have it towed to a shop, the crankcase drained and new oil put in. You may have a fighting chance of saving the engine.

First, can you clarify exactly what you mean by the “oil compartment”? Do you mean that you added water to the engine crankcase? Or to the power steering reservoir? Or to…?

Clearly, none of these “compartments” is meant to have anything other than the correct fluid placed there, but the exact location of this goof will allow us to give some specific advice.

And, while you are at it, I think that I am not alone in wondering why you would add water to anything other than the windshield washer fluid reservoir, or perhaps the radiator. Can you elaborate on what you were attempting to do?

Did you accidentally add 8 cups of water through the oil filler cap rather than put it in the radiator overflow tank? I take it this is not a hypthetical question?

As pointed out, water is a terrible lubricant even if it stays liquid. Hoever, the churning of the oil in the crankcase will turn the oil into an emulsion which has very poor lubricating qualities. As this emulsion is pumped to the bearings the water will likely turn into steam with the additional heat, making it an even worse lubricant.

To exactly answer your question, you probably did some damage to your engine; however, short distance drivers who live in a cold climate often accumulate 4 cups of water in their engines due to condensation. Such engines have a short life, but do not destory themselves immediately.

If the engine still runs OK, and you have drained the oil shortly after you put the water in and refilled it with fresh oil, I would just keep driving it. Your engine life will be shorter, but we don’t know by how much.

I remember reading the specifications on submersible well pumps that had bearings that were water lubricated. If the seal failed, the pump operation wouldn’t be affected. However, running a bearing submersed in a well is a lot different than the termperatures in an internal combustion engines. I just wanted to point out that water has been used as a lubricant.

I just wanted to point out that water has been used as a lubricant.

Yeah, and gasoline cools and lubricates your fuel pump. I’m sure that vegetable oil lubricates something at Newman’s Own! Anyway, the point here is that a mechanism (such as an engine) is designed to be lubricated in a very specific way, and any deviation from this risks major damage.

Gasoline can also be used as a refrigerant. If you want to cool a can of beer quickly, attach a string to a can of beer and dip it into gasoline. Twirl the beer around rapidly with the string. You may want to repeat the process. The evaporation of the gasoline will quickly cool the beer.

If OP gives us some more info, we can maybe assess the degree of damage. If the exposure to water was very short, some bearing damage may have resulted, but the engine may run for quite a whole yet.

Years ago EXXON invented the “Aunt Minnie test” for cold weather lubrication. It involved a car with automatic choke started at 0F or so and driven a mile or so then shut off. This resemble Aunt Minnie driving to the 7-11 for her morning paper. My father-in law did exactly that during his last years.

The oil in the crankcase turned eventually into 1/3 water, 1/3 gasoline and 1/3 oil! This was also the answer to those mysterious rising oil levels! Even this did not wreck the engine instantly; it would start using oil badly at about 50,000 miles and from there it was downhill all the way.

Don’t smoke while you are doing this!

Hmmm…The mythical Aunt Minnie was apparently not smart enough to have her morning paper delivered!

First of all thank you for answering my question. That afternoon, I had some freinds come over and drain the oil. They also poured rubbing alchol in the oil filler cap and ran the engine about 45 seconds. This evaporated any water that may have been in the engine. Then they put new oil in. It has been a week since that happened and the car is doing fine. I have a 2005 chevy malibu. What kind of life do you think on the engine will I have? Another 4 years or what?

That afternoon, I had some freinds come over and drain the oil. They also poured rubbing alchol in the oil filler cap and ran the engine about 45 seconds.

I hope they drained that alcohol and running the engine. Alcohol is used in small amounts with gasoline to “dissolve” the water in the gas. You don’t try that trick with the oil. If you need to remove alcohol from gasoline, but the dry gas product from the auto parts store, not rubbing alcohol.

Doc, you know i have the utmost respect for you, but I drive in a cold climate and if I pulled my drain plug and four cups of water preceded the oil coming out I’d have heart failure. Even when I had my pickup, which never went far in its later years…four cups of water? I’d have had a stroke!