# Help, please. Flooded car with water. NAF!

**URL:** <https://boards.straightdope.com/t/help-please-flooded-car-with-water-naf/748644>\
**Category:** Factual Questions\
**Created:** [March 11, 2016, 2:14pm UTC](https://boards.straightdope.com/t/help-please-flooded-car-with-water-naf/748644 "2016-03-11T14:14:26Z")\
**Posts on this page:** 17\
**Page:** 1

<div class="post-metadata">

**Author:** ![applebetty](https://avatars.discourse-cdn.com/v4/letter/a/4af34b/32.png) [@applebetty](https://boards.straightdope.com/u/applebetty)\
**Post date:** [March 11, 2016, 2:14pm UTC](https://boards.straightdope.com/t/help-please-flooded-car-with-water-naf/748644/1 "2016-03-11T14:14:26Z")

</div>

So the water was too deep and the engine died. Is there anything I can do to get it started? It’s been pulled out of the water but when I turn it over all I get is a metallic clunk. I was stupid, I know.

---

<div class="post-metadata">

**Author:** ![Inigo\_Montoya](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/inigo_montoya/32/124_2.png) [@Inigo\_Montoya](https://boards.straightdope.com/u/Inigo_Montoya)\
**Post date:** [March 11, 2016, 2:54pm UTC](https://boards.straightdope.com/t/help-please-flooded-car-with-water-naf/748644/2 "2016-03-11T14:54:25Z")

</div>

Could be anything depending on how deep you got. If water got into the engine it could be water locked. Normally you just have air in the cylinders, which compresses easily and the engine can turn over. Water does not compress. If water was pulled into a cylinder you may as well have a steel block in there and the engine will not budge.

Pull the spark plugs and see if you can get it to turn over. If you’re water locked, the water should shoot out of the spark plug hole.

---

<div class="post-metadata">

**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\
**Post date:** [March 11, 2016, 2:59pm UTC](https://boards.straightdope.com/t/help-please-flooded-car-with-water-naf/748644/3 "2016-03-11T14:59:55Z")

</div>

Note that water-locking an engine can ruin it.

---

<div class="post-metadata">

**Author:** ![applebetty](https://avatars.discourse-cdn.com/v4/letter/a/4af34b/32.png) [@applebetty](https://boards.straightdope.com/u/applebetty)\
**Post date:** [March 11, 2016, 3:00pm UTC](https://boards.straightdope.com/t/help-please-flooded-car-with-water-naf/748644/4 "2016-03-11T15:00:20Z")

</div>

Cool, thanks I’ll have to try that!

---

<div class="post-metadata">

**Author:** ![jz78817](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jz78817/32/1028_2.png) [@jz78817](https://boards.straightdope.com/u/jz78817)\
**Post date:** [March 11, 2016, 3:08pm UTC](https://boards.straightdope.com/t/help-please-flooded-car-with-water-naf/748644/5 "2016-03-11T15:08:13Z")

</div>

If you’re hearing a metallic “clunk” when you try to turn it over, I fear you may have broken one or more connecting rods, or broken the crankshaft.

---

<div class="post-metadata">

**Author:** ![Philster](https://avatars.discourse-cdn.com/v4/letter/p/13edae/32.png) [@Philster](https://boards.straightdope.com/u/Philster)\
**Post date:** [March 11, 2016, 3:20pm UTC](https://boards.straightdope.com/t/help-please-flooded-car-with-water-naf/748644/6 "2016-03-11T15:20:07Z")

</div>

Water essentially won’t compress, so cranking an engine with water in it usually results in catastrophic failure.

Remove the spark plugs and seek professional care.

.

---

<div class="post-metadata">

**Author:** ![applebetty](https://avatars.discourse-cdn.com/v4/letter/a/4af34b/32.png) [@applebetty](https://boards.straightdope.com/u/applebetty)\
**Post date:** [March 11, 2016, 3:31pm UTC](https://boards.straightdope.com/t/help-please-flooded-car-with-water-naf/748644/7 "2016-03-11T15:31:17Z")

</div>

OK, thanks for the info, guys. I probably have to go car shopping soon. I worked all night so I’m napping first.

---

<div class="post-metadata">

**Author:** ![3130](https://avatars.discourse-cdn.com/v4/letter/3/ccd318/32.png) [@3130](https://boards.straightdope.com/u/3130)\
**Post date:** [March 11, 2016, 3:32pm UTC](https://boards.straightdope.com/t/help-please-flooded-car-with-water-naf/748644/8 "2016-03-11T15:32:55Z")

</div>

From my experience its unlikely you broke any rods or the crank.

Usually the engine will die from air deprivation before major damage can occur, unless you were riding hammer down through the lake or something.

Like others have said, pull the spark plugs, crank the car over until there isnt any more water vapor shooting out of the plug holes.

Change the oil, then crank it over again for a minute or two before reassembly.

Dont crank for more than 20-30 seconds at a time as you risk burning out the starter.

---

<div class="post-metadata">

**Author:** ![enipla](https://avatars.discourse-cdn.com/v4/letter/e/54ee81/32.png) [@enipla](https://boards.straightdope.com/u/enipla)\
**Post date:** [March 11, 2016, 3:35pm UTC](https://boards.straightdope.com/t/help-please-flooded-car-with-water-naf/748644/9 "2016-03-11T15:35:11Z")

</div>

It may simply be your starter or starter solenoid. That’s the first thing I would look at.

---

<div class="post-metadata">

**Author:** ![August\_West](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/august_west/32/18069_2.png) [@August\_West](https://boards.straightdope.com/u/August_West)\
**Post date:** [March 11, 2016, 3:39pm UTC](https://boards.straightdope.com/t/help-please-flooded-car-with-water-naf/748644/10 "2016-03-11T15:39:39Z")

</div>

I used to be an avoid off-roader and have seen dozens of vehicles that were temporarily dead due to wet engine electrics.

99% of the time you just need to park your car for the day in a sunny spot with the hood open for 4- 24 hours.

---

<div class="post-metadata">

**Author:** ![Daylate](https://avatars.discourse-cdn.com/v4/letter/d/9dc877/32.png) [@Daylate](https://boards.straightdope.com/u/Daylate)\
**Post date:** [March 12, 2016, 12:27am UTC](https://boards.straightdope.com/t/help-please-flooded-car-with-water-naf/748644/11 "2016-03-12T00:27:16Z")

</div>

Fresh water or salt water? Makes a huge difference.

---

<div class="post-metadata">

**Author:** ![Joey\_P](https://avatars.discourse-cdn.com/v4/letter/j/919ad9/32.png) [@Joey\_P](https://boards.straightdope.com/u/Joey_P)\
**Post date:** [March 12, 2016, 1:22am UTC](https://boards.straightdope.com/t/help-please-flooded-car-with-water-naf/748644/12 "2016-03-12T01:22:57Z")

</div>

I had one or two friends get that much water into the engine, it was never the same and the car was eventually replaced.  
Another friend had the interior flooded as well. Her mechanic suggested waiting a few weeks before she ‘noticed’ the problem to report it. The reasoning was that if she reported it right away, the insurance company would pay to have it dried and cleaned but in the mechanic’s experience, she would spend the rest of that car’s life dealing with mold/mildew/smells that she’d never be able to get rid of. His suggesting to wait a few weeks was so that the mold would already have taken hold and the insurance company would total it.

IOW, my suggestion is that you do what you can to get your insurance company to replace the car if water got in the cab, if it only got in the engine, you should probably try and get them to replace the engine (unless the car is old enough to total it). I wouldn’t try fixing it.

---

<div class="post-metadata">

**Author:** ![Ignotus](https://avatars.discourse-cdn.com/v4/letter/i/ecc23a/32.png) [@Ignotus](https://boards.straightdope.com/u/Ignotus)\
**Post date:** [March 12, 2016, 1:46am UTC](https://boards.straightdope.com/t/help-please-flooded-car-with-water-naf/748644/13 "2016-03-12T01:46:38Z")

</div>

Please, also provide a good (i.e. one that wouldn’t make the insurance guys go ROFL!) explanation for how your car got suddenly drenched!

---

<div class="post-metadata">

**Author:** ![Isilder](https://avatars.discourse-cdn.com/v4/letter/i/cc9497/32.png) [@Isilder](https://boards.straightdope.com/u/Isilder)\
**Post date:** [March 12, 2016, 9:01am UTC](https://boards.straightdope.com/t/help-please-flooded-car-with-water-naf/748644/14 "2016-03-12T09:01:22Z")

</div>

> [@Ignotus](#):
>
> Please, also provide a good (i.e. one that wouldn’t make the insurance guys go ROFL!) explanation for how your car got suddenly drenched!

The news shows a video of a driver who approached the flood water, and did a U turn to drive away, then in a fit of bravado, or perhaps fear of appearing to be a scaredy cat, did a 2nd u turn and drove right into the water… which was way too deep for a petrol sedan.

---

<div class="post-metadata">

**Author:** ![Isilder](https://avatars.discourse-cdn.com/v4/letter/i/cc9497/32.png) [@Isilder](https://boards.straightdope.com/u/Isilder)\
**Post date:** [March 12, 2016, 9:13am UTC](https://boards.straightdope.com/t/help-please-flooded-car-with-water-naf/748644/15 "2016-03-12T09:13:31Z")

</div>

And yeah a petrol engine can be easily stopped due to the water.  
What happens is that water hits the fan and belts and sprays everywhere, and the water shorts out the spark plug lines… no sparks…

a little while after the engine is stopped, the water has boiled away, and the vehicle can go again.  
you can open the air filter and check to see if it is soaked… if its just damp it should be ok, but if it looks like its been flooded with water, then maybe you have water in the cylinders… its possible that trying to crank it over with water in the cylinders ruins it, but often enough the bonnet (aka hood) protects the engine from getting water into the air intact, even when the bonnet is under water… the intake is right up at the bonnet level !.

---

<div class="post-metadata">

**Author:** ![jz78817](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jz78817/32/1028_2.png) [@jz78817](https://boards.straightdope.com/u/jz78817)\
**Post date:** [March 12, 2016, 11:52am UTC](https://boards.straightdope.com/t/help-please-flooded-car-with-water-naf/748644/16 "2016-03-12T11:52:20Z")

</div>

> [@Isilder](#):
>
> And yeah a petrol engine can be easily stopped due to the water.  
> What happens is that water hits the fan and belts and sprays everywhere, and the water shorts out the spark plug lines… no sparks…
> 
> a little while after the engine is stopped, the water has boiled away, and the vehicle can go again.  
> you can open the air filter and check to see if it is soaked… if its just damp it should be ok, but if it looks like its been flooded with water, then maybe you have water in the cylinders… its possible that trying to crank it over with water in the cylinders ruins it, but often enough the bonnet (aka hood) protects the engine from getting water into the air intact, even when the bonnet is under water… the intake is right up at the bonnet level !.

_usually_ the starter doesn’t have enough torque to damage anything trying to crank a hydrostatically locked engine. The danger is if you try to charge through deep water at higher engine speeds; when the piston slams into incompressible water things can bend or break.

---

<div class="post-metadata">

**Author:** ![Inigo\_Montoya](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/inigo_montoya/32/124_2.png) [@Inigo\_Montoya](https://boards.straightdope.com/u/Inigo_Montoya)\
**Post date:** [March 14, 2016, 1:57pm UTC](https://boards.straightdope.com/t/help-please-flooded-car-with-water-naf/748644/17 "2016-03-14T13:57:15Z")

</div>

> [@Ignotus](#):
>
> Please, also provide a good (i.e. one that wouldn’t make the insurance guys go ROFL!) explanation for how your car got suddenly drenched!

Please no.

Don’t make stuff up to try and save face. Just tell me what happened and trust me to remain professional, maybe even share a “shit happens” moment with you. If your “better” story sounds wrong and doesn’t check out, the whole tone of the claim will change and you’ll see delays while I take us through extra investigative steps make sure you’re not presenting a fraudulent claim. There’s coverage for “I misjudged the water depth.” Let that be your story–it gives you coverage.
