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My 2003 Opel Agila 1.2 Petrol, has a high air intake. Here is the approximate location of it:

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Here is the engine bay, showing the air intake on the left. enter image description here

Is the height of the bottom of the chassis the maximum height I can drive through without hydrolocking? (This question is bordering on offtopic, sorry!)

Would I hydrolock, even though the intake is really high?

Would there be any risks of other mechanical failures (like destroyed electronics)?

  • I wouldn't go deeper than halfway up the front bumper. That's not a scientific conclusion. I just think it's a safe but useful limit. – Captain Kenpachi Aug 25 '15 at 11:26
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If you really want an intake that will likely survive deep water, you're going to need something more like:

Jeep with deep water intake

However...

Is the height of the bottom of the chassis the maximum height I can drive through without hydrolocking? (This question is bordering on offtopic, sorry!)

Would I hydrolock, even though the intake is really high?

You might think that you're in the clear for deep water because, you know, intake is pretty high and all. However, are you certain that that's as low as your intake tract goes?

In my car, the intake is in approximately the same place. The air then passes down near the passenger's front wheel through a silencer and then back up to the air filter. In the silencer, there's a little hole to allow the occasional splash water a place to drain. Obviously, if water can get out, it could potentially get back in.

I would say that your maximum depth is the lowest point of the intake tract. However, I provide no warranty on that estimate. If you're really worried, find another route.

Would there be any risks of other mechanical failures (like destroyed electronics)?

Yes, of course. It's very common to end up with water in the spark plug holes, especially in an inline engine. If you look, your battery is lower than that intake point. At a bare minimum, you should expect something dramatic if you submerge your entire battery while trying to run the car.

Even better, if the water is higher than the tops of your wheels, I'd expect the car to start floating (or at least getting light and scary). If you spent too much time in a puddle deeper than that, I'd start worrying.

And, as always, never drive into flowing water if you don't know the depth and the current. People die like that disturbingly easily.

  • " It's very common to end up with water in the spark plug holes, especially in an inline engine." Why especially in inline engines? – Jerreck Aug 25 '15 at 14:30
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    @Jerreck, because the spark plug holes are vertical. My engine is flat so it's harder for it to retain water in the spark plugs. A V engine is somewhere in between. Assume that the probability distribution is something like the cosine of the angle from vertical. – Bob Cross Aug 26 '15 at 0:56
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Bear in mind that unless you were to get out and measure the height of the water, you won't know how deep it is.

Furthermore, as you drive into the water you will create a bow wave so the actual water level may change and still cause water to be sucked into the engine.

You also risk wetting the coil pack which would stop your engine running and potentially leave you stranded mid-water.

Best advice has to be, if you don't have to drive into water; don't.

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