Tight viscous coupling

[silverbullet]

Not being one to shy away from controversy...biology is not a valid excuse. Yet another example of the disparity of so-called "equality" in western society. You can't help it any more than we can
Something tells me that this may not be terribly well recieved, but I'm going with it as I'm in a cheeky mood

[syncrosimon]

This is why we never get anywhere on these proper discussions and the topic will rear up again, if we can just keep civil then we are making progress. I find the technical aspect of this very interesting. But without a definitive answer from VW about the existence of the de-coupler we can only speculate as to it's existence. Shame really.

[syncrosimon]

Something tells me that this may not be terribly well recieved, but I'm going with it as I'm in a cheeky mood

Me too.

[syncropaddy]

Technical discussions should contain facts and documented evidence on the subject matter. Technical discussion will get nowhere when people cant tell the difference between unqualified opinion and facts. If I want to learn and discuss gardening I will talk to a qualified gardener, I wouldnt talk to a policeman. There is no harm in asking questions in a technical discussion as long as a qualified person gives the correct answer. There is far too much unqualified opinion floating about on forums like this one. Sometimes it can be scary!

[peasant]

Well, all I can say is that the VC saved my bacon this morning.

Hit a surpriiiiize! patch of black ice right in the apex of a pretty tight bend at speed and lost complete control. First the front went nearly straight ahead and the the a*** came swinging round. Only for the fact that the front wheels were transferring power, got traction and pulled me out of the spin (and the rear back on the road) am I sitting here now. Had 4WD been de-coupled ...so would I be now ...no gentle glide into the adjacent field or a nasty bump into the ditch/hedge ...this one was a sheer drop of several meters with roll-over potential and sturdy trees at the bottom to end it all.

So ..the gods of four wheel drive have shown me the light (and a dark patch in my pants ) ...no de-coupler for me, thankyouverymuch, ever!

[jed the spread]

Well, all I can say is that the VC saved my bacon this morning.

Hit a surpriiiiize! patch of black ice right in the apex of a pretty tight bend at speed and lost complete control. First the front went nearly straight ahead and the the a*** came swinging round. Only for the fact that the front wheels were transferring power, got traction and pulled me out of the spin (and the rear back on the road) am I sitting here now. Had 4WD been de-coupled ...so would I be now ...no gentle glide into the adjacent field or a nasty bump into the ditch/hedge ...this one was a sheer drop of several meters with roll-over potential and sturdy trees at the bottom to end it all.

So ..the gods of four wheel drive have shown me the light (and a dark patch in my pants ) ...no de-coupler for me, thankyouverymuch, ever!

I am not commenting on de-couplers here (i am over them) but the situation you have just spoke of.

I had a very similar thing happen to me behind the Co-op in Hove. I set off from home and it was chilly but defiantly no frost at all. I would have been in 2wd as it was a journey of 60 miles or so and would have wanted to "protect" some brand new parts on my van on the straight motorway. popped the heater on and all was well till I turned round the corner in Hove and the back of the van slid out toward some railings (black ice). The same happened to my front wheels Mr Peasant, just pulled me out of a right pickle and saved me more than double the price of the thing I am now over. SOOOOOOO glad.....

jed

[Aidan]

Since we like a nice pdf, here's something to get your head round decoupler boys

note the front pinion shaft is one piece, no billet shaft involved, just a specific unique pinion shaft - don't know the code never seen one and the switching that was built into the intermediate case involving valving the case of the box itself, has anyone ever seen one of these set ups ? Must crawl under the ClassicParts/Museum ons sometime and check them out

[syncrosimon]

Is the housing the same as the VC front unit Aidan. That's a big gap in there.

[syncrosimon]

Well, all I can say is that the VC saved my bacon this morning.

Hit a surpriiiiize! patch of black ice right in the apex of a pretty tight bend at speed and lost complete control. First the front went nearly straight ahead and the the a*** came swinging round. Only for the fact that the front wheels were transferring power, got traction and pulled me out of the spin (and the rear back on the road) am I sitting here now. Had 4WD been de-coupled ...so would I be now ...no gentle glide into the adjacent field or a nasty bump into the ditch/hedge ...this one was a sheer drop of several meters with roll-over potential and sturdy trees at the bottom to end it all.

So ..the gods of four wheel drive have shown me the light (and a dark patch in my pants ) ...no de-coupler for me, thankyouverymuch, ever!

There is no accounting for bad driving and poor judgement.

[peasant]

There is no accounting for bad driving and poor judgement.

True ...but if we all were perfect drivers, our cars could still come with belt brakes, solid rubber tyres, karbide lamps and selectable 4WD

[Sync16]

The point is that when driving in dodgy conditions you can engage the decoupler and drive it just like a normal syncro, it just gives you the option as well as THREE pull switches and lights to match.

[jed the spread]

Like putting lipstick on a pig?

jed

[silverbullet]

Moving on...

Is the housing the same as the VC front unit Aidan. That's a big gap in there.

Curiouser and curiouser...do my eyes decieve me or is that showing cable operation to the transmission-mounted valve too?

[HarryMann]

No, think that (11) is just schematic for 'any suitable connection' - in practice was incorporated into the unit

The question is, as Aidan says, does that front diff unit look the same cross-section as the ones we have that take a VC..

[Aidan]

yes it's a bowden cable operating the selectable 4wd , the gearbox intermediate case was machined and fitted with 5 spigots for the vacuum system, the feed would have been teed off at the reservoir rather than running to and fro the dash, it would automatically engage 4wd if you selected G gear, and that would stay in until manually disengaged with the dash lever, or 4wd could be selected by the dash lever for operation in all gears
and yes the case for front diff is same but pinion and rear bearing are different, even oil volume the same - would have made no sense to have a different case and fitting just because no VC in there and the operation could have been swapped to VC susequently if required, changing parts as required; codes for both difflock and non difflock shown, but only ever 5.43 final drive ratio it seems