Viscous Coupling?

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I feel like I'm speaking a different language to you. I have no idea what you on about.

For me this is an ok explanation of a viscous coupling:

Saint.V8 said:
Depends on Year....

Works by locking up when one axle is turning faster than the other (indicating a loss of traction) Works on the same or similar principal to the Viscous unit on the engine fan or the Torque convertor...one axle is drving a rotor disc, the viscous fluid flows through a stator plate to the other axle which has a rotor disc....if one rotor disc travels faster than the other, the viscous fluid gets churned up up and this flows through the stator plate and starts draging the other disc round...if the speed of rotation is large enough the fluid starts thickening and turning faster, this in turn turns the other rotor disc faster to match it....until both axles are turning at the same speed....
Click to expand...

It doesn't even mention a difflock.

Jeez, all I did was ask what happens to the viscous coupling when I engage difflock and none of you has been able answer with anything but vitriol.
 
shoppinit said:
I feel like I'm speaking a different language to you. I have no idea what you on about.

For me this is an ok explanation of a viscous coupling:



It doesn't even mention a difflock.

Jeez, all I did was ask what happens to the viscous coupling when I engage difflock and none of you has been able answer with anything but vitriol.
Click to expand...

Cos you are dense and havent googled it like suggested you dont get it. The last line tells you wot ya need to know: both axles are turning at the same speed. Difflock.done.
 
shoppinit said:
I feel like I'm speaking a different language to you. I have no idea what you on about.

For me this is an ok explanation of a viscous coupling:



It doesn't even mention a difflock.

Jeez, all I did was ask what happens to the viscous coupling when I engage difflock and none of you has been able answer with anything but vitriol.
Click to expand...

ON A VEHICLE WITH A VCU THERE IS NO MECHANICAL DIFF LOCK.....

The Viscous unit by the method mentioned IS the difflock....when one axle turns faster than the other the VCU starts LOCKING UP to ensure both axles start turning at the same speed.....

I did not answer '...with vitriol...' I answered your question of how the VCU works....

Simples....
 
No, obviously you didn't answer with vitriol - this is your first post since I asked my question. Thanks for that.

I get that the viscous coupling will lock the axles together when there is a speed differential. In that case, the answer I had earlier is wrong - my rear wheels (or at least one of them) should have turned when my 2 front wheels were driven. No?

So then what happens when I engage difflock? Now, just to be sure we're talking about the same thing, I have taken some pictures:

diff2.jpg


diff1d.jpg


What effect does moving that lever have, if any, on the viscous coupling?

I'm not asking what 4WD is or what the difference between a land rover and a range rover is, give a guy break FFS.
 
shoppinit said:
No, obviously you didn't answer with vitriol - this is your first post since I asked my question. Thanks for that.

I get that the viscous coupling will lock the axles together when there is a speed differential. In that case, the answer I had earlier is wrong - my rear wheels (or at least one of them) should have turned when my 2 front wheels were driven. No?

So then what happens when I engage difflock? Now, just to be sure we're talking about the same thing, I have taken some pictures:

diff2.jpg


diff1d.jpg


What effect does moving that lever have, if any, on the viscous coupling?

I'm not asking what 4WD is or what the difference between a land rover and a range rover is, give a guy break FFS.
Click to expand...
YOU ARE STUPID!!!!!!!!!!! AND THERE IS NO VISCOUS ON YOUR VEHICLE!!!!!!!!!!!!!!!!!God....
 
Then that's all anyone had to say. Not the stupid bit, obviously :). The bit about me not having a viscous coupling.

Goonarmy, I think anyone reading your posts and anyone reading mine will be able to make up their own minds about who is "dense", "stupid" and a "knob".
 
you, cos i put it in me second post but ya didnt read it. And others put it too. And you clearly didnt google it as suggested, which you clearly needed to do.Peopl that dont read posts or search get short shrift here. Dick.
 
shoppinit said:
No, obviously you didn't answer with vitriol - this is your first post since I asked my question. Thanks for that.

I get that the viscous coupling will lock the axles together when there is a speed differential. In that case, the answer I had earlier is wrong - my rear wheels (or at least one of them) should have turned when my 2 front wheels were driven. No?

So then what happens when I engage difflock? Now, just to be sure we're talking about the same thing, I have taken some pictures:

diff2.jpg


diff1d.jpg


What effect does moving that lever have, if any, on the viscous coupling?

I'm not asking what 4WD is or what the difference between a land rover and a range rover is, give a guy break FFS.
Click to expand...
Yours won't have a VCU fitted as you have a mechnical Diff Lock....

With the Diff Lock Disengaged, your fron axle and rear axle will be able to turn at different speeds hence why on a rolling road, your front axle and prop can turn with no effect to the rear axle and prop....

If you had Diff Lock engaged by moving the lever to the left, when you turn the front wheels the rears will turn at the same speed as they are now locked thogether through the Diff Lock.

Vehicles with a VCU or if the Diff Lock is jammed on...should not be used on a 2 wheel rolling road as this will damage the Transfer Box as the rears won't be able to turn....as such braking tests should be carried out using a Force Gauge (can't remember the name) positioned on the footwell and then driven and braked on a quiet stretch of road....

If you have a later Classic , P38 or L322 which has the VCU or Torsen system....and your MoT tester tries to use a 2 wheel rolling road for a brake test....drag him out of the car, beat him with a broom handle then take your car to someone who knows what they are doing!
 
Thank you, Saint.V8. That was a very clear answer. And not a single childish insult in there! Double thanks!

I was under the impression that this was my VC:

diff3.jpg


So now I'm not sure what it actually is. Difflock mechanism?
 
shoppinit said:
Thank you, Saint.V8. That was a very clear answer. And not a single childish insult in there! Double thanks!

I was under the impression that this was my VC:

diff3.jpg


So now I'm not sure what it actually is. Difflock mechanism?
Click to expand...
Thats the Hand Brake Drum that acts upon the Rear Propshaft...

YourMechanical Diff Lock is contained in the Transfer Box bolted to the Gearbox.

Even if yours had the VCU, the VCU is internal to the Transfer Box with no external indication at all....
 
OK thanks. I have a much better understanding now.

I had googled viscous coupling, as some users politely advised me to, and the images I got looked a lot like that handbrake drum.

viscous coupling - Google Search

That'll teach me for googling stuff.

Now, I must say that most of you have made me thoroughly sick with your intolerance and unpleasantness to a stranger who had the misfortune to ask a question that was obvious to you, but not to him.

So you'll be glad to hear I won't be back.

Or I might come back with a different user name and you'll be nice to me because you'll have no idea, eh, goon? ;)
 
shoppinit said:
OK thanks. I have a much better understanding now.

I had googled viscous coupling, as some users politely advised me to, and the images I got looked a lot like that handbrake drum.

viscous coupling - Google Search

That'll teach me for googling stuff.

Now, I must say that most of you have made me thoroughly sick with your intolerance and unpleasantness to a stranger who had the misfortune to ask a question that was obvious to you, but not to him.

So you'll be glad to hear I won't be back.

Or I might come back with a different user name and you'll be nice to me because you'll have no idea, eh, goon? ;)
Click to expand...
:clap2::clap2::clap2:
 
shoppinit said:
OK thanks. I have a much better understanding now.

I had googled viscous coupling, as some users politely advised me to, and the images I got looked a lot like that handbrake drum.

viscous coupling - Google Search

That'll teach me for googling stuff.

Now, I must say that most of you have made me thoroughly sick with your intolerance and unpleasantness to a stranger who had the misfortune to ask a question that was obvious to you, but not to him.

So you'll be glad to hear I won't be back.

Or I might come back with a different user name and you'll be nice to me because you'll have no idea, eh, goon? ;)
Click to expand...
From those images, it is an easy mistake to make, but the Range Rovers VCU is internal to the Transfer Box with no external 'drum' to see...

I do hope your tirade has not been aimed at me, a I try to be as informative as possible (most of the time)....

PS: the VCU is Item no 4...
41250d1359814305-viscous-coupling-classic_vcu.jpg
 

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Saint.V8 said:
I do hope your tirade has not been aimed at me, a I try to be as informative as possible (most of the time)....
Click to expand...
Absolutely not! I would hope that would be obvious from context!

As for the others, they have reacted exactly as I expected them to do. *chuckle*
 
Saint.V8 said:
Depends on Year....

Works by locking up when one axle is turning faster than the other (indicating a loss of traction) Works on the same or similar principal to the Viscous unit on the engine fan or the Torque convertor...one axle is drving a rotor disc, the viscous fluid flows through a stator plate to the other axle which has a rotor disc....if one rotor disc travels faster than the other, the viscous fluid gets churned up up and this flows through the stator plate and starts draging the other disc round...if the speed of rotation is large enough the fluid starts thickening and turning faster, this in turn turns the other rotor disc faster to match it....until both axles are turning at the same speed....

Testing is carried out by putting main box in neutral, jack up ONE wheel, Handbrake off, and trying to turn that wheel....it should be stiff and may need a breaker bar on the wheel nuts to rotate.....this is good.

If it is locked solid, this is bad....

If the wheel rotates freely, this indicates a broken Diff, Half Shaft or Prop Shaft....

IIRC - the VCU was introduced in 1991 for tha classic, but can't be 100%....

To see if yours has it - the ratio transfer lever will have a 'Diff Lock' position i.e. you have to move the lever to the left to engage Diff Lock...and to the right to dis-engage...

Don't engage Diff Lock on a hard surface, it should be done on loose surfaces only, as with it locked up you potentially are making both axles turn at the same speed when going round corners, and on hard roads, you could wind up the gearbox ,and couse issues....
Click to expand...

I have just read this whole thread and can see where the confusion has begun right at the beginning. This guy got a great description of how a VCU works but then a slip up up let him believe that he had one.
 
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