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Driving through water. hydralock

5327 Views 14 Replies 9 Participants Last post by  Randalface
Hey Guys,
I live in Firestone, CO and we just experienced some redik flooding. On my way out of town I was blocked by a concrete median, water in front and water all around. There was no other option as water levels were rising.

I waited for all the SUVs in front of me to judge the dept and then proceeded in after. I put the car in full lock and 1st gear through it nice and easy. Water touched the front bit of the hood but didnt go over the hood. My concern was hydra-locking the engine. Luckily I had not installed my AEM CAI yet so it was the stock snorkle.

Fortunatly I did not hydralock the engine, I powered through with some slight clutch slipage (expected for submerging it). Do you think there is some water still in the intake that I should take apart? Do you think the intake filter is shot?

I doubt water got in but do you think its gone now that the car runs fine? What about undercarriage consequences?

Let me know so I can remedy potential issues sooner better than later.

Thanks guys.
2013 STI 4 Dr.
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There is an intake snorkel at the bottom portion of the hood. Good chance you sucked in some water. I would replace the filter and remove spark plugs and try to turn it over so it spews out all the water. Once the water is gone, maybe do an oil change for good luck and hopefully you won't have any more issues.
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well here is the thing, I know I said hydralock but the car runs and starts fine. I am just assuming i may have done some damage without locking up the motor
hydrOlock :lol:

If you had done this your car would not be running. I am sure you are fine. Engines are tolerant to a little moisture introduced into the intake track. A lot of water they are not. To hydrolock it you have to be pulling enough vacuum through the intake track to pull water up into it. Water is heavy and unless the water level was above your IC / TB chances are you are not going to pull it all that way.

You can run a cone filter in a hurricane and the velocity of air entering it will cause the water to drop out of suspension at sharp bends and velocity changes in the intake.

You are good to go. Check the car over when everything dries out, but you probably didnt do any damage.

If you had water in your engine, your engine would have told you, believe me.

Inspect and move on. :tup:
You will instantly know when you hydrolock the motor, and with water that high you definitely would have with a cai.

I would definitely at minimum check the intake. BPV can also house water as well as various vac lines they're easy to get to, and can give you an idea if any made it very far into the intake track.

I was finding water in odd nooks and crannies for quite some time after hydroloking a previous car. Surprisingly it survived undamaged.
I'd suggest changing your rear diff fluid. Its vent will allow water in when submerged. It's not uncommon for more offroady Subarus to either run the vent higher or to just drain and refill after it was submerged.
grr, yeah I may check into that as well. Intake was bone dry but passenger rear seat carpet was damp. evidently there is a drain hole or opening that isnt plugged there. Smells like bad water. I've covered the whole floor with rice and airing out the car.

Adds new meaning to "ricing out your ride" :lol:
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I live down in The Springs and have had some experience with this. Also yea, the rain was crazy! As said if you actually got hydrostatic lock the engine would have to be evacuated before it would run. I had a friend that locked up the engine in his jeep some years back four-wheeling outside of Deckers, CO. It started again and ran for a while, but a connecting rod was damaged. It eventually broke and punched a nice square hole in the pan. I also helped another guy who got locked up bad in the same water crossing. He had a cool old FJ40 with a GM diesel in it. He sucked water with the turbo at full spool, but since diesels are so robust it ended up being fine. We just took out the glow plugs and the nastiest black water shot out of all the holes. Then some carb cleaner and starting fluid and it was running again.

The one thing I would recommend is change all the fluids in the car. Engine, tranny, diff, brakes, clutch, and power steering. I have little doubt most if not all your fluids are contaminated. If left unckecked that could cause some expensive problems down the line. My $.02.
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everything i read about hydralock is that its covered under insurance
The one thing I would recommend is change all the fluids in the car. Engine, tranny, diff, brakes, clutch, and power steering. I have little doubt most if not all your fluids are contaminated. If left unckecked that could cause some expensive problems down the line. My $.02.
That's a bit unnecessary. Certain things, yes, but not all of it. Brake system is sealed, clutch system is sealed, tranny does have a vent, but it curves in such a way that water can't get up into it (car would have to roll over for water to get inside), power steering is sealed.

Rear diff is a for sure, since it's known that Subaru's diff vent (and most diffs in general) will allow water in when submerged. I've helped a few Jeep guys at work run diff breather vents to their light bars so its as high as possible. The engine oil is a possibility, since any potential water in the intake could have made it though the vent system into the crank case. However, that's pretty serious water intake, and the engine would've suffered hydrolock anyway. Since it's water, once the engine is up to operating temp the water will turn to vapor and be removed through the PCV system.
That's a bit unnecessary.
I won't disagree with that, but I'm the guy stuff happens to so I tend to err on the side of caution.
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I really wish they would find a way to compress water so you don't have to worry about hydra locking your motor.. :tup:
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