Wading depth

[bowfer]

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

You send them my way.
I evidently know far more about motorbikes than them.

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.

Two strokes do work slightly differently in that pressure waves in the exhaust ‘scavenge’ the exhaust gases out of the cykinder.
This is why exhaust design in a two stroke is crucial, using conical ‘expansion chambers’, whereas 4 strokes can just be any old straight pipe.
But sucking water into the engine….nah….

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.

Precisely where you want an air intake.
Lower = denser air.
Not so great in floods, granted.

 

[mg4mc]

Back in the day I had a V6i Capri that I hydraulically locked going through a ford. I hadn't realised the air intake was right down below the bumper. Luckily, I had kept the revs quite low.

I got dragged out, took the plugs out and turned it over to great fountains of water shooting out sideways from the Vee engine that soaked a couple of onlookers! Plugs back in and it started, no damage done, very lucky.

Sucking up the exhaust, nah. Lot's of 4x4's have an air snorkel for the inlet when wading but the exhaust just stays below the water. Serious sorts also extend the breathers on the axles and gearbox higher up as well.

 

[Ian Key]

I emailed MG customer services asking about the wading depth was for the MG4. Here is the reply:

Dear Mr Key,

I apologise for late reply as I have been looking through our specifications.

Its not something that we have published, or been provided with, however, under normal circumstances on any motor vehicle , it is roughly just below half way of the wheel.

This pretty much coincides with the lower sill below your doors.

 

[tsedge]

I emailed MG customer services asking about the wading depth was for the MG4. Here is the reply:

Dear Mr Key,

I apologise for late reply as I have been looking through our specifications.

Its not something that we have published, or been provided with, however, under normal circumstances on any motor vehicle , it is roughly just below half way of the wheel.

This pretty much coincides with the lower sill below your doors.

This makes sense as manufacturers won't guarantee no water ingress through the door seals.

 

[Ian Key]

This makes sense as manufacturers won't guarantee no water ingress through the door seals.

In other words, if you feet are getting wet inside the car it's too deep

 

[bowfer]

In other words “no clue so basing it on ICE”

Wading depth on the original Leaf was 700mm

 

[tsedge]

In other words, if you feet are getting wet inside the car it's too deep

Yes, in as much as they will be responsible for any interior damage under warranty. Policies vary though, some makers test and certify to a deep depth.

 

[tsedge]

In other words “no clue so basing it on ICE”

Wading depth on the original Leaf was 700mm

Indeed, but then they were serious about it and tested the Leaf extensively in deep water. Pretty sure MG have not.

 

[Tangoed Man]

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?

My guess would be that the seals are designed to withstand that, but not hydrostatic pressure of total immersion.