Drowned engine. Change oil?

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Long story short, I drove through a puddle that turned out to be more like a small lake and sucked up enough water to drown the engine. I pulled the plugs and cranked it to pump out the water, got new plugs, a new air filter, and a new starter (it was on its way out anyway). Assuming I can it started again and nothing internally is borked, should I go ahead and change the oil or wait until the OLM goes off? It'll probably go off sometime next month. No water is visible on the dipstick, fwiw.
 
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Originally Posted By: MinamiKotaro
Long story short, I drove through a puddle that turned out to be more like a small lake and sucked up enough water to drown the engine. I pulled the plugs and cranked it to pump out the water, got new plugs, a new air filter, and a new starter (it was on its way out anyway). Assuming I can it started again and nothing internally is borked, should I go ahead and change the oil or wait until the OLM goes off? It'll probably go off sometime next month. No water is visible on the dipstick, fwiw.
I would change it with some cheap oil and again (to your normal oil) after a couple of hours of running. Most boat engines die because of ingesting water.
 
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Oil floats on water, so loosen the plug and pull it just long enough to check for water. If no water is present take a long drive to get the oil good and hot and evaporate any moisture.
 
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Originally Posted By: Donald
I would change it with some cheap oil and again (to your normal oil) after a couple of hours of running. Most boat engines die because of ingesting water.
+2
 
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Originally Posted By: MinamiKotaro
No water is visible on the dipstick, fwiw.
The bottom 3 or 4 quarts won't show on the stick, but enough water would raise the level of the oil. Is the level abnormally high?
 
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If your engine is worth more than a couple of hundred bucks you could go all out and change the oil and oil filter a couple of times over the next few hundred miles. You might also want to rattle your pcv valve and look around the air box and any hoses that are attached, too. Do take your car out and get it up to operating temperate a few times to cook off any moisture in hidden places inside the engine. Oil lubricates much better than water. Late blooming problems in these situations are valve lifters, camshafts and their attached mechanisms if any and the piston rings. That's why being a big spender and changing the oil a few times can help even if there is no evidence right now of damage.
 
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Originally Posted By: MinamiKotaro
Long story short, I drove through a puddle that turned out to be more like a small lake and sucked up enough water to drown the engine. I pulled the plugs and cranked it to pump out the water, got new plugs, a new air filter, and a new starter (it was on its way out anyway). Assuming I can it started again and nothing internally is borked, should I go ahead and change the oil or wait until the OLM goes off? It'll probably go off sometime next month. No water is visible on the dipstick, fwiw.
Originally Posted By: asand1
Oil floats on water, so loosen the plug and pull it just long enough to check for water. If no water is present take a long drive to get the oil good and hot and evaporate any moisture.
^This first, then
Originally Posted By: Donald
I would change it with some cheap oil and again (to your normal oil) after a couple of hours of running. ...
^THIS....although I'd be inclined to do 2 short runs, with a UOA after the first one to be certain.
 
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Originally Posted By: MinamiKotaro
..Assuming I can it started again and nothing internally is borked..
Yup, first things first. Let us know how it goes...good luck!
 
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Usually when water meets an engine, that's it for the engine because unlike air, you can't really compress water so something else has to go. So the real key part is if you can start the engine. In the long run, you're probably better claiming it got flooded and file an insurance claim. Once things get wet, it doesn't always dry out and you may have mold problems later or electrical contacts that will now rust quicker and you're just looking at more problems a few years down the road.
 
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Does it run? Usually when a running engine ingests enough water to shut down a rod bends since water does not compress... I'd change the oil before even trying to start it. Your also going to want to change your transmission fluid since ATF and water don't get along and a hot transmission when dunked will suck water in threw the vent.
 
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I would let it idle for at least 30 minutes after it gets hot before driving it. I've took a car swimming before with no ill effects to the engine. interior smelled a bit until I could pull it up and dry it out...
 

MinamiKotaro

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Well, I changed the oil. What went in as 4qts T6/1qt ??? came out as a bunch of chocolate milkshake. I dumped in 5qts of the dozen or so gallons of 5w30 PYB I've got laying around plus an old PL15436 that's been sitting in the shop for about two years. I ran that up and down the road until everything was nice and hot, then dumped it. I changed one more time with even more 5w30 PYB and a Driveworks DW5436 filter. I'll leave that in until the OLM goes off, probably about the middle of next month. I may refill with more of my T6/whatever Frankenblend or just use PYB. The engine idles a bit lopey but otherwise seems ok. Time will tell.
 
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yeah just run it until it grenades, it sounds like you are already better off than most with it running as-is.
 
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Drowned lots of motors, first step is always pull the plugs and pump any water in the cylinders out, if you can open up the throttle plates and look for any pooled water in the intake, mop it out if there is any. Then pull the dipstick and check for milkshake or high oil level. Regardless of the dipstick check, plan on changing the oil as soon as you get back to home base. Change oil and filter, run to operating temp, change oil and filter again and run for at least 30 minutes, then do a final change with your regular oil and hope nothing major happened.
 
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