Diff breathers

[RTG]

Hi all,
do we know whether it comes with/needs diff breathers?

 

[Elijah]

Solid axel so definitely needs diff breathers.. no pictures of them or Where they route to. We asked in SF tour about them and weren’t given specifics 

 

[emax]

Should be routed to under the bonnet. I'll otherwise do it myself.

 

[OzyGrenie]

Hi all,
do we know whether it comes with/needs diff breathers?

Not only Diff breeathers, ZF Gearbox and the Transfer Case breathers. Wonder where they finish or even have a non return valve???? (At least just under bonnet height)

 

[DaveB]

Not only Diff breeathers, ZF Gearbox and the Transfer Case breathers. Wonder where they finish or even have a non return valve???? (At least just under bonnet height)

I assume at least 800mm off the ground
I doubt they would quote 800mm wading depth and then have the breathers lower than that. They would then have to cover any damage under warranty

 

[DCPU]

Solid axel so definitely needs diff breathers.. no pictures of them or Where they route to. We asked in SF tour about them and werenât given specifics

I going to guess that there are two breathers per axle, both located just inboard of the wheel stations.

On the front axle:

which is routed up the outside of the chassis and either terminates here in a valve or is a connector block to extend further into the engine bay:



And on the rear axle:


which is routed up the rear radius arms somewhere:

 

[Tazzieman]

I assume at least 800mm off the ground
I doubt they would quote 800mm wading depth and then have the breathers lower than that. They would then have to cover any damage under warranty

I suspect one of the 200 or so German engineers Ineos engaged has considered this!
"You only had one job!!!"

 

[DaveB]

I suspect one of the 200 or so German engineers Ineos engaged has considered this!
"You only had one job!!!"

What would they know about building a tough 4WD?????

 

[ECrider]

I suspect one of the 200 or so German engineers Ineos engaged has considered this!
"You only had one job!!!"

Herr D.B. Reathers

 

[DaveB]

I going to guess that there are two breathers per axle, both located just inboard of the wheel stations.

On the front axle:
View attachment 7796462
which is routed up the outside of the chassis and either terminates here in a valve or is a connector block to extend further into the engine bay:
View attachment 7796463
View attachment 7796464

And on the rear axle:
View attachment 7796467
View attachment 7796468
which is routed up the rear radius arms somewhere:
View attachment 7796473

The Breathers are normally from the diffs not the wheel area?
There should be 3 diff breathers, 1 transmission and 1 transfer case.
I could be wrong

 

[klarie]

What do you mean deairing valves ?

 

[klarie]

@DCPU correct - in sense of wading depth they re not a restriction. - (One Way) Our posts were nearly simultaneous

 

[DaveB]

And

Not necessarily. The breathers are in theory mostly one way vent valves.

The old Landrover ones just screwed into the axle tube and so were never related to wading depth.
View attachment 7796480

People started extending them as the design of the jiggle valve was prone to getting dirt in and just remaining open all the time.

and yet no diff or transmission breathers and these ones were known to cause a problem.
OOPS I forgot - Landrover

 

[DaveB]

Diff breathers need to be two way not one way valves
If air can only get out when hot then what happens when it cools down?
That is why they are called breathers.
Not my comments below just some crazy person.

Where raised breathers become important, is when you’re trundling along with the short-stick locked in causing everything in your driveline to heat up. Wheel bearings, axles, CVs, diff centres, pinions – the works. As the air in your diff housings heats up, it expands, and pressurises the diff. The breather lets it release this pressure out into the atmosphere, instead of out via your axle seals.

So far, so good. So why would you want raised diff breathers? Because invariably, there’s going to be a water crossing, river, or boat ramp that you’ll want encounter during your travels. If you’re anything like me, you’re not going to want to sit there for hours waiting for your driveline to cool down before you get your hubs wet. As we said before, when the driveline gets hot, it vents air out. When it cools down, it sucks air back in. If your diffs are hot and the breather goes underwater, it is going to suck litres of water through the breather. In some cases, breathers have a one-way valve that closes when the pressure flips. In this case that water can be sucked in through your axle or pinion seals.

 

[Tazzieman]

Speaking of old land rovers , the little brass wading plug you screw into the bellhousing. the one that drops in the mud, never to be seen again!

 

[DCPU]

It's almost the same design as used by Toyota and many other manufacturers ~ so not just a JLR issue.

 

[DaveB]

It's almost the same design as used by Toyota and many other manufacturers ~ so not just a JLR issue.

This is what a diff breather kit looks like
Totally different to a non-return valve based breather
They are two way and allow the diff to breath out and back in from a controlled location.

 

[Tazzieman]

Or you leave it permanently installed as it stops oil from leaking all over your drive; just take it out periodically to drain into an old tin...

I have a gravel driveway , so what has originally come out of the earth's crust is returned , slowly

 

[klarie]

Ah I see .. ve seen similar 2way valves on gearboxes and engine. I am not a mechanical engineer. So what I gonna do - ask my car mechanic. Need to talk to the guy anyway. My front camera became dysfunctional during snowfall on Saturday ..

 

[emax]

This is what a diff breather kit looks like
Totally different to a non-return valve based breather
They are two way and allow the diff to breath out and back in from a controlled location.

View attachment 7796483

That's what I'd expect. It's independent from having a snorkel or not, since wading always causes air in the diffs to expand or shrink. Even if I drive through only 30cm of water.

There is a wading limit for each car. So the breathers have to be mounted above that limit. I personally would avoid to have another gasket in a snorkel.