He does have a valid point in that theoretically, sudden temperature changes will crack stuff if they are very hot initially and their thermal properties can't withstand it.

Engine blocks are far too strong to cause any problems though as hits thermal expansion properties and temperature ranges it can cope with are far better than the stresses a quick dip in water will cause and the exterior of an engine is only around 50-90degrees anyway apart from maybe the exhaust manifold.

Pouring cold water into a severely overheating engine that's lost all its coolant is a different matter however!


The only worry you would ever have when wading I
is cracking a headlight as glass would be brittle enough to crack.

The waiting to wade when a vehicle is cold is only just to prevent the axles sucking in too much water through a pressure drop when the axle and oil is suddenly cooled if your breathers aren't high enough or seals aren't brilliant.
in the case of the engine if you weren't 100% confident in your breathers, crank seal etc.


Basically... He's talking sh!t and using engineering theory to help his scaremongering

Oh... And I'm an engineer too lol.

Although heated wading would be quite nice. No more cold wet feet etc. would be like driving in the bath.

Many moons ago I had a lada niva that drove with the bonnet under the water. The engine was hot. The engine had a fixed metal cooling fan. It was petrol...but well sealed up.

It was at a trial, so plenty there if it went wrong, and we knew the water was quite deep in a quarry. Drove in and the Lada wobbled from side to side and floated had to wait till it filled with water so the wheels hit the bottom. It drove to the other side and out. Opened the doors and let the water out.

Nothing broke. not the fan or the block so I know for a fact you can drive through cold water, I was sitting in it!! with a hot engine with a fan on it.

...
And the second to attempt the course in a landrover 90 rolled it on to its roof the hill down to the water. The rest of the day was spent recovering the landrover
No photos of me in the water but I have of the landrover

All them ex-soviet cars would probably run on ****. The water is no bother for it! I got a mate collects eastern bloc cars. Best one is the big ural truck thingy

I've not had any problems wading in my TD5.

I went by Moreton today, you would have a problem at the moment...

ScratchyDom said:

I went by Moreton today, you would have a problem at the moment...

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I don't doubt it. That side current can be quite vicious.

ratty said:

I don't doubt it. That side current can be quite vicious.

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Depth n'all, the footbridge was pretty much underwater. My phone was outa battery else I would have taken a photo.

what he's talking about is thermal shock, metals on the whole (certainly all structural steels) are sufficiently malleable/ductile ( can never remember which) to withstand the limited thermal gradient there is when wading, as the previous posts have said the engine has a water cooled jacket, in fact to really have thermal shock problems you'd need to be well in the cherry tempreture ( >800celcius) and even then all you would do is warp the casting.
as for the other issues I agrre with previous posts - glass from flood lights - defo switch them off, axles, sort you breathers out mousse is horrible.
me, I'm a materials science graduate.

and yes, snorkels originally came about to lift the air intake above the the dust coming from the wheels in a desert.

trax99 said:

and yes, snorkels originally came about to lift the air intake above the the dust coming from the wheels in a desert.

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That's the purpose of the mushroom top. T'is to filter out the dust particles.