MadDog

We're in our monsoon season here in Albuquerque. Lastnight I was driving through a storm that dumped about 2 inches in an hour. It was pretty intense. There was a low spot in the road ahead and after gauging the depth of the water on the cars ahead of me, I decided to go for it. It was probably 8 inches deep. I'm well aware of the need to keep your foot on the gas when going through a "puddle" like this, but it was to no avail. The car stalled out. The interesting thing is that the engine immediately lost compression. Believe me, having blown an engine before, I'm well aware of what that's like. The very first time I hit the starter, I could feel the rough, unbalanced feeling as the rotors turned, indicating that one or more chambers was making no compression. Of course, with no compression, the car doesn't even try to start. I was stuck in this water for about 40 minutes, trying occasionally to start the car.

Finally, I just decided to waste the battery and lay on the starter for an absurdly long time. I held the starter on for about a minute and finally the car reved to about 3k and died. During that spurt, I could tell the compression was still poor since it was running so roughly. A third time of about a minute on the starter and I got it running. It ran - but like crap.

I spent the next 2 hours driving around town trying to get the engine back in shape. At first, the power was down and there were a couple of RPM bands that were really rough. It felt just like when I blew the last engine. But, it continued to improve as I drove. After I had wasted an entire tank of gas I finally shut it down. It now runs and starts just as before, so I'm guessing the compression is back to normal.

I could totally understand the loss of compression if I had tried flooded the engine myself trying to get the car started after it stalled. But, it had lost compression immediately - before I even tried to start it the first time. I have trouble believing that water got in the intake as its pretty well protected behind the bumper like most of us with the GReddy "CAI". But maybe that's what happened.

Just wanted to post a warning. Even just 8 inches of water was enough to knock my 8 out of commission.

chiefy

People tend to forget that the Spark Plugs and HT Leads are at the bottom of the engine bay or very near to it. 8 inches of water probably would bring the car to halt. Amazed you got it going again - just shows what they can really take.

MadDog

That was my first thought - that the plugs were shorted. But I don't think that's it. The car actually lost compression. Otherwise, the car should have run fine once the plugs dried out - which would have been just a few minutes after I got it going. The resulting heat would have dried them. But the symptoms of lost compression persisted for at least a 45 minutes of driving.

NMOcho

MD That must have sucked. I think it would take less water for me as I have the Revi Cold air intake its a snorkle just asking to suck up water. I have sat out the few rain storms not risking it..

rotarygod

It is very possible for a rotary to survive getting water in it. Ask me how I know! Remember it doesn't take much fuel at startup to lose compression so a little bit of water will do it too. The reason why your engine is fine is bacause of the tip shape of the apex seals. As the rotors turn, the seals rock back and forth against the housing. You have to see it on a model to fully understand how. Because of this, the apex seals are rounded. Any moisture in the chamber will fill whatever it can, this includes the slight open area under the rounded portion of the apex seals. Since water can no be compressed, it puts stress on the seals from anywhere that it can. In this case from underneath the apex seals. This pushes them back up into their grooves and lets the water and pressure bleed off into the next chamber. It doesn't take much moisture for this to happen. Once the water is completely out, compression will slowly come back. The longer the engine sits like this, the harder it is to get compression back. The seals are steel and can rust. Surface rust deelops in a matter of minutes and can slightly cause the seals to stick. This combined with excessive moisture in the engine is why it took you a little while to get it going again. Now that you've literally been flooded, change the oil and filter. You will have some water dilution into the oil system as it will have slightly leaked past the oil control rings.

Remember that speed affects how high the water comes up. Even 8" of water can come over the hood if you are driving fast enough. The slower you go with the rpm's up, the better which may even mean first gear.

It's a good thing you weren't driving a piston engine car. You'd be doing a rebuild for sure!

MadDog

I suppose it could have been water intake that caused it afterall. The inlet is so sheltered that it seems bloody unlikely, but so does the fuel flooding scenario. The whole incedent was pretty surprising.

From now on, I'm driving the A4 Quattro any time there's a grey cloud in sight!

MazdaManiac

iTrader: (3)

Monsoon seems to have forgotten us here in Phoenix. Its been dry as a bone for almost a year, excepting the 3 or 4 moderate thunder showers we've had in the last 4 months.
No standing water, though.

When I started reading this thread, I felt compelled to open up a browser window to America West Airlines again!