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Accidentally Ran water while engine was not running....

Chadharter

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I was letting my engine run to get the oil hot to change the oil and when I killed the motor, I forgot to turn water off. Probably had it on 3-4 minutes before I realized it. I went through with oil change. Afterwards it started fine. I ran it for 5-10 minutes and it seemed fine. I know, I screwed up. Should I be worried? If it starts and runs fine???
 

Julian

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Check the oil and make sure it isn't milky. If it is, change it ASAP (multiple times).

But it is unlikely have have an issue. Running on the hose you have to have high water pressure for it to back up into the engine....gravity prevents it.
 

Grover70

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I was cleaning my engines out after a day in the salt water. A kink in the hose probably shut 75% of the water off as I ran the engine. I should have noticed the drip instead of the stream of water coming out out of the boat. Alarm went ding ding, I shut off the water completely and then the engine. No problem at all. Engine just got a little hot and did what it should, tell me. She's still running strong and the oil looks normal.
 

Cobra Jet Steering LLC

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The only issue with running the water with the engine off is that the exhaust pushes the water out of the muffler so if you had the engine off the water would eventually fill the muffler and allow water to go back to the engine, if it did that you would have known when you tried to start the engine.. As Julian said if the oil looks clear of water you dodged a bullet..
 

Beachbummer

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The worst scenario is when the engine is running and water is ingested..that is usually pretty terrible news.... If the engine is off when it happens, mostly there is no damage unless you are very unlucky. If the oil looks good, don't sweat it. If the oil looks milky, you just need to replace the oil. The engine still runs well, so you did not break the expensive stuff that can break with the Water Lock.
 

Cobra Jet Steering LLC

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Also if you ever do get water in your oil the sooner you remove it the better!!!
Pull as much of the milky looking oil out of the engine as you can. Then add 1 qt .of Dextron 2 transmission fluid in place of one qt of oil and replace the rest of oil with some inexpensive oil and run the engine on a hose for a while. The Dextron 2 will mix the oil and water and make it easy to remove the remaining water when you remove the oil again and replace it with good oil and a new filter, you should be good to go . Also Dextron 2 is a super detergent so it removes all the sludge buildup in old engines.
 

Chadharter

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Thanks for all the replies! Getting ready to head to Fort Morgan, AL. Weather doesn't look that great but hopefully I get some time in and around Mobile Bay.....thinking about making a run in to Gulf Shores to Robinson Island.....
 

Liveto99

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I flush at the ramp and the boat is tilted backwards. I ran the wrong motor till I got the ding ding ding. I started the other one and it ran fine and no water in the oil. From that I think if you are tilted back you are pretty safe or mine would have hydro locked.
I’m getting old and marked witch key each side controls, now I know why my dad has marked everything he owned with markers.
Getting old sucks, but it beats the alternative.
 

haknslash

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As a precaution, if you ever run water into your engine without the engine running its best to NOT attempt to start the engine immediately after to see if it s ok. You should remove the spark plugs and then crank the engine over so it would pump out any water that would have possibly made it on top of the cylinders. If you were to flood the engine with water sitting on top of the cylinders you can destroy all sorts of things from the head to even down in the block.
 
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Liveto99

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Yes you are correct.
For anyone who wants to know what happens when there is water in the cylinder instead of air, it can not compress so some part of the engine bends or brakes when the cylinder goes to the top. I’m not sure on the water in the oil that everyone talks about or how it would get there unless it blows by the rings? So little though, I figure a rod would bend first. But I would like to know?
 

JDRacing

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I’m not sure on the water in the oil that everyone talks about or how it would get there unless it blows by the rings?
I think the answer to this is that, if the muffler fills up as Jeff from Cobra Jet Steering referenced, water would eventually back up to the exhaust manifold and then into the cylinder(s) through an open exhaust valve. At least one of the them will be open with the engine shut off. Running the engine with the hose connected and water on causes positive pressure through the muffler, forcing the water out.
 
Last edited:

Bennett White

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I was letting my engine run to get the oil hot to change the oil and when I killed the motor, I forgot to turn water off. Probably had it on 3-4 minutes before I realized it. I went through with oil change. Afterwards it started fine. I ran it for 5-10 minutes and it seemed fine. I know, I screwed up. Should I be worried? If it starts and runs fine???
This just happened to me today. I forgot to turn the water off. Maybe a minute or two if that. Went ahead with warming up the engine and changed the oil. Everything seems okay. I hope…
 

Cobra Jet Steering LLC

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Update Dextron 2 does not work any more they changed the formula and don't even sell it any more, so I came up with another way to help remove water from the engine but it is a bit dangerous, so I won't post it here .
 
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