Tight viscous coupling

[Russel]

Syncro drivetrain setups are a personal choise decided by budget and useage.
There is nothing wrong with the VC setup and suits more people than the decoupler.The decoupler and billet or SP VC is only for extreme traction which 99% of syncros will never need.
I would think that the VC would suit you.
Russel

[syncropaddy]

Get a new VC. This argument could go on for ages....... VW fit VCs, they don't fit De Couplers any more. There's your answer!

[syncrosimon]

What are you on about, VW fit vc's as part of 4x4 drive trains, most modern vehicles decouple in one way or another, because for most of the time you will never need it. The VW system is actually very old fashioned, as it would be, being the first viscous coupling 4x4 system on the market.

De coupling is better. Having constant 4x4 is a compromise.

Dont get me wrong, getting a new vc is a good choice, and cheaper to install, but a syncro with a decoupler is a better more useful practical vehicle, you will save the extra cost in tyres, worn front end components, mot can properly check your brakes, you can rotate individual wheels, the vehicle can be towed. It is better.

[peasant]

Having constant 4x4 is a compromise.

Might want to tell that to Subaru and Audi

[syncrosimon]

Yeah, fine on a brand new tight vehicle, we are talking about old vehicles that need careful looking after. If you want your gearbox, cv joints, diffs, and tyres to last then a decoupler really helps. It is the best long term investment for a syncro.

Internally switchable 4x4 systems, although more expensive, give a better overall package than constant 4x4.

Even my kangoo trekka 4x4 has a decoupler, it is just controlled by the traction control computer, it still has a VC. It's a more expensive system to have, but better.

What is the point of 4x4 on a dry road. None.

[desert rat]

Update!!!

I have started the work on the van now - have removed the propshaft and the armour and to start by replacing the viscous coupling, but when i removed the VC i have found there is quite alot of play in the shaft that comes out of the front diff. So if anyone knows how much play should be in this shaft please let me know!
but looking at this it looks like i will have to have the diff reconditioned!!!

[toomanytoys]

When you say play what, up down in out? or rotational?
Aidan is your man for a rebiuld if required and sure he will be along to offer advice...

Not going to tread back over the decoupler thoughts.... but I now have a decoupler (not fitted yet) but that becuase I do a lot of motorway mile and wanted to reduce the straqin on the drive system... I also have a tight VC which means I have the best of both worlds... (how long the tight VC lasts is anyones guess, but it will save me fitting and removing the propshaft for events/motorway) Yes I did consider a new VC and prob would have gone that route... but a decoupler came available from a deal I did .....

[desert rat]

The movement is all ways - up and down and in and out and rotational. But i had not yet decided whether or not to get a decoupler as well - but this diff will have to be sorted anyway!

[toomanytoys]

Give Aidan a bell....

[desert rat]

Yeah i have already rung Aiden this morning and sorted it out with him - he says it is knackered and will have to be rebuilt!!

[Macflai]

Get a new VC. This argument could go on for ages....... VW fit VCs, they don't fit De Couplers any more. There's your answer!

You and your VC's... Decoupler rules amigo!

[syncropaddy]

syncropaddy wrote:Get a new VC. This argument could go on for ages....... VW fit VCs, they don't fit De Couplers any more. There's your answer!



You and your VC's... Decoupler rules amigo!

Victor.... go back to sun bathing and that silly La** R**ver you have!

[HarryMann]

The movement is all ways - up and down and in and out and rotational.

Is this with the end casing off or on?

VW soon discarded the decoupler and solid* shaft when they latched onto what a super handling, better braking vehicle the VC equipped one was... they made two or three? of the former (while waiting for Prof. Peschke to complete his evaluation of the Rolt/Ferguson patents and then forward a suitable final design). Subsequently they made more than 32,000 using the VC...
It really wasn't a serious attempt at a production vehicle, just a first stab by Steyrs, to get soemthing on the road for testing I imagine... VW didn't like it one bit I think, so took on Peschke to get cracking on a full-time 4WD system asap and told Styers to keep playing with their clunkety clunk until it was ready. One test drive and the marekting men smiled broadly and suggested the board approved the VC layout (once all the test figures from Steyrs added up nicely)

There's a good chance this is what attrracted the favourable press reviews and to some extent, ensured it's success as a refined and sensible vehicle for Mr Average Joe rather than a quaint throwback to clunky old military vehicles.

The re-manufactured decouplers are not really a ripoff, as making the sliding dog clutch parts in a low production fashion is very different to tooling up for mass production - very! It's a nice thing to have, but a shame the whole front drive-line can't easily be disengaged.

*solid, not billet... this modern euphemism wasn't used until recently when silly marketing men started knocking out over-engineered shiny bits for Barry Boys on CNC machines, wasting 90% of the raw material in swarf, instead of forging or casting them as they should. e.g. billet gearlevers, billet wing mirror mounts I bet half the time the grain of the original billet is used in the wrong direction anyway!

Hehehe, I like a good rant I do

[syncropaddy]

You go Clive.....

I entirely agree with that man.

[HarryMann]

Maybe of interest historically...

Viscous planetary diff built for a prototype Reliant Scimitar* 4x4 in 1973

Scimitar Ferguson 4x4

A one off Scimitar was built using Tony Rolt's (from FF - Ferguson Formula) 4 wheel drive technology.

*You know, those fibreglass bodied 2+2 hatchbacks with a Ford 3 litre V-6