Wading depth

[Captain]

Last night I was driving along the Cornish lanes when I came upon a ford of quick moving water indicating just over a foot deep
I didn't fancy trying to turn so slowly waded through
After I got a couple of warning to hold the wheel (which I was) but no other after affects...
My Range Rover has a "maximum wading depth" but I've not seen one for the MG...
Has anyone else had issues driving through water...?

 

[Ian Key]

I guess it depends if you have an undertray scoop/bulge on how deep you can go.

 

[siteguru]

I went through some flood water last winter ... I have a small bulge (oo-er) and I think the flood water helped to clean the tray!

 

[MartinSEsr]

I always think a foot is ok but you need to go really slowly. Rufford Ford is always on YouTube with petrol engines being wrecked due to ingesting water as they all go too fast and create a bow wave.

Forces are high though from water, so crawling through makes sense.

 

[PristDean]

When an MG4 meets a Ford.....I believe someone else went through water, but at a greater speed, which caught their warped under tray and ripped it off.....One new tray and £700 pounds later..... 1-0 to Ford

 

[Rolfe]

I always think a foot is ok but you need to go really slowly. Rufford Ford is always on YouTube with petrol engines being wrecked due to ingesting water as they all go too fast and create a bow wave.

Forces are high though from water, so crawling through makes sense.

I was always told the issue was taking your foot off the accelerator so the engine throttled back and sucked water up the exhaust pipe. Special lessons in motorcycle school about how to feather the throttle to avoid this. Tricky. Go too fast and you're in trouble, but throttle back and you're in trouble too.

With an EV you don't have that issue, just don't drive too fast through water.

 

[siteguru]

With an ICE the trick is to ride the clutch* as you're going through - that keeps the engine revs up without getting too much forward motion.

* in a manual; if you have an automatic then you're snookered.

 

[Rolfe]

Now you've got me trying to remember what I did with my DSG Golf. I did have to go through water sometimes and I always managed not to stall. Once I had to go past a car that had stalled in it.

Of course the motorbike that I learned all that on had a clutch.

 

[Tangoed Man]

Aside from the obvious water ingress into the air intake or the exhaust with combustion vehicles, the other hidden issue is water ingress into the cills where the small CAN control wires can often be routed. Get those wet and after some while your vehicle is virtually a write-off as the cost to replace the control wires is usually prohibitive. So, best to check with any vehicle if the control wires are routed low down where water can ingress.

 

[bowfer]

With an ICE the trick is to ride the clutch* as you're going through - that keeps the engine revs up without getting too much forward motion.

* in a manual; if you have an automatic then you're snookered.

The ‘trick’ is just not to get water into the air intake, end of.
Doesn’t matter how many revs, manual or auto.

There’s a whole series of videos on TikTok featuring one ford in England that attracts sightseers, you see umpteen cars making a hash of it and you hear their engines hydraulic locking and failing in mechanical pain.
You also see people successfully negotiating it in manuals and autos (and EVs).
They don’t go too fast or too slow and create a ‘bow wave’ in front of their cars, effectively pushing the water away as the car goes through.

It’s quite an entertaining page.

 

[Rolfe]

See above - someone said the ford is now closed, possibly permanently.

 

[Ian Key]

The bow wave creates a trough behind it so allowing the car to go through deeper water without getting it in the engine.

The action that kills ICE cars in deep water is trying to start them if they've stalled and the end of the exhaust is below the water. Turning the engine over creates a vacuum and sucks the water through the exhaust into the engine.

 

[tsedge]

There are an awful lot of plastic pieces ripped off cars going through fords, mostly due to excessive speed. Getting water where it isn't wanted is not a good idea with any car, so I always avoid this if I can.

 

[bowfer]

The bow wave creates a trough behind it so allowing the car to go through deeper water without getting it in the engine.

The action that kills ICE cars in deep water is trying to start them if they've stalled and the end of the exhaust is below the water. Turning the engine over creates a vacuum and sucks the water through the exhaust into the engine.

Hmmm, I’ve got this pending filing in urban myth.
Engines don’t suck air via their exhausts in any circumstance AFAIC.
Put your hand over a motorbike exhaust when pressing the starter and there’s no vacuum at all, only blowing.
Any engine with water ingress is purely from the intake, I think.

 

[Ian Key]

Hmmm, I’ve got this pending filing in urban myth.
Engines don’t suck air via their exhausts in any circumstance AFAIC.
Put your hand over a motorbike exhaust when pressing the starter and there’s no vacuum at all, only blowing.
Any engine with water ingress is purely from the intake, I think.

It probably depends on the engine. I know someone who stalled her VW beetle in a ford and when she tried starting it again ruined the engine because water had been sucked in to it and the water level was nowhere near the air intake.

 

[NickHeynes]

I always think a foot is ok but you need to go really slowly. Rufford Ford is always on YouTube with petrol engines being wrecked due to ingesting water as they all go too fast and create a bow wave.

Forces are high though from water, so crawling through makes sense.

I was always told to, get out, test the depth then when your happy, drive in slowly and create a bow wave, thus pushing the water away from the vehicle. It's letting the wave wash back on you that causes more problems. Also ,if the water is slow moving drive downstream ,just a little as you are moving with the water and your bow wave will make the water even shallower.
Driving in at speed just causes a massive disturbance , the car slows as a result of the extra force working against it water floods back . Hey ho flooded engine.

 

[Rolfe]

The compilation of clips of Teslas going through that ford included one that ripped its front number plate off going too fast.

 

[Rolfe]

Hmmm, I’ve got this pending filing in urban myth.
Engines don’t suck air via their exhausts in any circumstance AFAIC.
Put your hand over a motorbike exhaust when pressing the starter and there’s no vacuum at all, only blowing.
Any engine with water ingress is purely from the intake, I think.

Well, go talk to the ACU instructors who gave me the lessons in riding through water, then.

 

[MartinSEsr]

Well, go talk to the ACU instructors who gave me the lessons in riding through water, then.

It could be that 2-stroke engines are different? My understanding is that exhausts dont ever suck water up and it's it getting into the induction system that is the problem.

On my golf, the engine air intake was just below the bonet lip, ie quite high. But on many BMW, it is low down near the bottom of the radiator, hence the large number being water damaged in the videos.

 

[MartinSEsr]

Aside from the obvious water ingress into the air intake or the exhaust with combustion vehicles, the other hidden issue is water ingress into the cills where the small CAN control wires can often be routed. Get those wet and after some while your vehicle is virtually a write-off as the cost to replace the control wires is usually prohibitive. So, best to check with any vehicle if the control wires are routed low down where water can ingress.

I agree, but surely a drive at 70 mph on a M-way in torrential rain would get just about every nook and cranny soaked through on any car? Slowly going thru a 1ft ford wouldn't be very different?