What happens to an engine that takes in water? I've heard about people with cold air intakes going through deep pudles and sucking up water instead of air and blowing their motors. Exactly what gets damaged and how?

 

Well, you answered the first part of your question. When a CAI sucks up a puddle, that water goes straight into the engine.

The last one I saw that sucked a puddle bent the connecting rod that was on the compression stroke. The cylinder filled up with water, the valves all closed, and the piston tried to compress water into a space 9.2 times smaller than the cylinder. hehe...not gonna happen.

Luckily just the one rod got bent. The force wsa enough to stop the engine pretty much instantly. It basically hydro-locked. I would think that if you were driving hard and hit a puddle, the engine would have enough speed that it would run long enough to damage lots more. There's potential for broken connecting rods, broken or bent crank and probably blown valve seats as well.

 

yeah guys
this is not a pretty sight
it hurts me to see any engine hydro-locked
it's not saafe to drive around with a CAI when it's puoring rain
better get that bypass valve or a short ram
better safe than sorry

 

does a bypass valve guarantee the saftey of your engine or is it still possible to hydro-lock it.

 

Still possible, but you'd basically need a flash flood.

 

I've had my CAI on my 98 Civic EX for two years now and never had any problems. I live in NH and go to school in Mass, there are plenty of times after snow and rain Ive hit puddles without even thinking about it. (knock on wood)

 

I was with a friend when he drove though a huge puddle (it was a "duh" moment for both of us) and it immediately stalled the engine. After he cranked it for a while, it fired back up and ran for monthes until it was swapped out. That was a D15Z1.

We figured he only got a tiny bit of water in there, because after it was running again it purred like a kitten. The filter was dripping wet though.

 

What if it's only for a short period of time, like a few seconds. Afterwards, the car ran kinda boggy for about 5-10 minutes, then started clearing up. Now it runs okay, but gets bad fuel economy and the oil temp rises quicker than usual. Also, my compression is down in 3 out of 4 cylinders.

 

Water will quickly replace the oil coat on the cylinder walls, which causes a lot of friction and HEAT. That can warp the metal and/or rapidly wear down the cylinder walls and piston rings.

All sorts of bad stuff happens when you suck up water. A few seconds is more then enough to detroy and engine, hell, you can destroy it in 1/10 of a second.

 

My local shop said it's probably the piston rings too. Thanks!