Wanker of the day

[ARW]

[spuorgelgoog]

Do you think a shatnav might have been involved?

Owain

[Scott]

Genuine question: what actually happens if you do this? Does the water flood the electrics and bring the engine to a stop, or does it enter the exhaust pipe, or does it lift the wheels off the road?

I was taught to slip the clutch, rev the engine, never take your foot off the accelerator and proceed very slowly to avoid creating a bow wave. I was also taught the water has to be fairly shallow (but I cannot remember any figure).

[Tim+]

A lot depends on the vehicle but most modern cars have their air intakes low down (for cooler air maybe?) which means they?re very prone to ingest water in even quite shallow floods. No amount of engine revving will stop this.

Regarding bow waves, lots of contradictory advice around. I think a bow wave per se isn?t necessarily a bad thing as long as you don?t try to overtake it and have the water rise over the bonnet. You do need to be confident that your air intake is situated high up rather than low down.

Tim

[Scott]

Thanks. This is good advice. I think I was getting confused in thinking the exhaust pipe was the biggest problem when of course, as you say, the air intake is likely to be be more crucial. I will look tomorrow. My car is quite old (2008 Micra) so this may be a benefit?

[charles]

In my Anglia I managed to get through a "ford" where the 'tideline' on a stuck vehicle which followed me in was at 23" above road level.

[Ian Jackson]

In message <qe8r4t$qsn$ [e-mail], ARW [e-mail]> writes

If the car was a manual, the driver could have 'wound it out' of the water using the starter motor.

[newshound]

If you had ever tried that, you would realise how low the gearing is. You are going to flatten the battery and/or melt the starter motor and wiring before getting far.

If you take the plugs out, you can use the starter motor to wind a car up on to a set of ramps.

[newshound]

He went into that far too fast. Apart from flooding the air intake as someone else said, you need to avoid splashing too much water around the HT in a petrol car (although they are much less vulnerable than they used to be).

[Ian Jackson]

Have you ever had to drive a car without a disengagable clutch? I've had to (several times). It's surprising how quickly it 'takes off' from a standstill. The object of the exercise is usually to start it and drive off - but then changing gear can be fun, as well as stopping! However, I have to admit that I don't really know how you could go (on the level) purely on the starter motor.

[Dave Liquorice]

In that example I suspect the air intake got flooded, the engine ingested water and hydrolocked. Twonk, if hadn't gone in so hard and fast he'd have got through.

Modern electrics and connections are an awful lot better than they were, condensation in/on the distrubter cap was enough to stop a car in the old days...

Unlikely with the exhaust gases being pushed out by the exhaust stroke of the engine.

As in float, yes that can happen but how much depth is required depends on the vehical. A Land Rover Discovery has a wading depth of

70 cm (27") a mini about 25 cm (10"), note these are the depths to which the car should survive if driven sensibly, floating depth will be more.

Deep water is remarkably reluctant to get out of the way. I managed to get a Mondeo through a flood that was "a little deeper than I expected". Took an awful lot of go pedal and slipping of clutch just to maintain a slow walking pace, the water was just lapping up onto the bonnet. Starter motor was never quite the same afterwards but nothing else complained.

[Dave Liquorice]

Plenty of water cooling...

But isn't a low gear what you want? ie starter running high speed/low torque, wheels low speed/high torque.

When I ran out of fuel at a set of lights in the middle of Carlise I used the starter to wind the car across a lane of traffic to a relatively safe and out of the way spot to pour the 20 l jerry can of diesel into it an perform the the priming process. This was a Disco II though, put it low 1 and it just slowly moved with no more complaint than normal starting. B-)

[Steve Walker]

On some cars, pulling part of the system off would ensure that air was taken in from higher up.

SteveW

[Steve Walker]

Yes. I'd agree with that.

Probably unlikely to overheat when submerged in water though.

Only place I've done it (and without removing the plugs) was when an underbody spray in a carwash soaked the ignition and stopped me starting the car to drive out.

SteveW

[John Rumm]

I had to do it about 30 years ago. The GF and I were coming back from a night out, in the early hours of the morning. Got to the top of this humped back bridge, and realised it had turned into a lake, almost as far as the white car in the picture:

So I pondered what to do. In that time, another car cam up behind me, overtook, and managed to get through ok. So I thought ok, lets try.

By about half way though, the car was really not happy! It conked out in the middle with 30m or so up hill in either direction.

So after ruling out getting out to push (I was not sure if the water level was over the sills or not), a slapped it in second gear, and moved it in 10 second bursts on the starter. Got us out of the water and onto dry land. Left the car ten mins to drain, and tried restarting - it turned over and nearly caught - but not quite. After another couple of mins, it started and would idle, but you could not rev it. After a further 5 mins idling we were able to drive off again, and within a couple of mins all was back to normal. That was one occasion I was very pleased the car had a decent battery in it, as it got a good workout that night.

(got a few brownie points as well that night - she did not know you could do that :-)

[John Rumm]

Lots of modern cars use plug packs, and so don't have traditional HT leads.

[Harry Bloomfield]

Dave Liquorice wrote on 17/06/2019 :

There also the problem of aqua-planning, where the tyres grip is lost completely. The tyre is lifted off the surface completely, when the tyres bow wave is simply unable to escape. More likely the poorer the tread depth. You loose all braking and steering capability, as if on ice. The car in the video, shows some slight evidence aqua-planning.

[dennis]

You have to be careful as if the air intake has sucked in water then its incompressible and trying to move the car will bend things inside the engine. If its just damp electrics you will be OK.

What people forget is that if you drive into deep water you need to open the doors to let the water in or you will float off downstream.

[Brian Gaff]

Erm, how does that make him a merchant Banker? I'v heard of several Police cars getting stuck in floods over recent days. Brian

[Brian Gaff]

Yes the maps were all so old the were in . ark format. Brian