Donate SIGN UP

Cars in floods

Avatar Image
Kos | 14:56 Wed 20th Jun 2007 | How it Works
8 Answers
Whats the guideline for driving cars thru floodwater?
Will the engine cut out if the exhaust pipe is submerged?
Are diesels less likely to stall?
I've heard something about 'as long as the inlet manifold is not covered' you are ok- whatever that means!
Gravatar

Answers

1 to 8 of 8rss feed

Best Answer

No best answer has yet been selected by Kos. Once a best answer has been selected, it will be shown here.

For more on marking an answer as the "Best Answer", please visit our FAQ.
The exhaust gases should keep the exhaust pipe clear, diesels don't need any electric ignition parts, plugs coil etc and are unlikely to stall, the inlet manifold is generally the highest point on a standard engine, so if it were covered the water would be almost chest level, I think I'd be sitting on the roof now shouting for help. I think the technique is to drive through slowly and in a low gear with high revs.
Look at the height of the water on cars that are going through before you. Try to go through one car at a time, making sure that you are driving along the dotted line - zenith of camber point - make sure you drive slowly and don't get swamped by someone elses ' bow wave'. If you think your car won't make it stop, it's makes for very expensive repairs otherwise.
The two critical things are keeping the electrics and the engine air filter inlet orifice free of water, (not the inlet manifold, which is part of the engine). To be sure, this means driving through anything over a couple of inches of water depth at about 2mph. Plus, as mentioned, keep your revs up.
. (The Renault Espace air inlet was originally placed very low down by the front axle, and caused owners all sorts of problems in floods. Similarly, the Austin Mini distributor was placed low down and faced the left front wheel, making it very susceptible to getting wet).
I despair at news reports on TV where drivers zoom through foot-deep water without a care in the world. It's utterly crazy, and asking for trouble.
-- answer removed --
The main point is the air intake, which must not be under water, some cars have their air intake pipes very low e.g. under the headlight or front bumper grill. If water is sucked in to the engine it will try to compress it, which it can't. Usually what happens is the conrods bend, an expensive repair. I have seen it twice, once in a petrol 4 x 4 and once in a diesel saloon, both drivers entering a flood when all other drivers stopped.
Modern diesels work with computers and the likes so HDi or TDi is most likely not going to be as happy as an old style one.

If the water is moving be very careful entrering it as it doesn't take more than a few inches to sweep most cars down river.

And if the engine is hot, it's not a good idea. Last time I broke down, the recovery guy had just come from a lass who'd driven into a flood and cracked the engine. Very, very expensive.

Finally - remember that the bow wave effect will make the level of the water much higher for the car than surrounding it so even if it's an inch below anything critical, when you enter, it could swamp things inside. I did hear that opening your bonnet can help as it stops the belt spraying the water over the engine and electrics.
I drive a Citroen Picasso Deisel car, and although it is higher off the ground than most cars, I have read that the air intake is low - very annoying...
just as long as you keep your on the pedel and don't lift your foot it wont stall

1 to 8 of 8rss feed

Do you know the answer?

Cars in floods

Answer Question >>