Seized Viscous coupling on transfer box Big job ?

This site contains affiliate links for which LandyZone may be compensated if you make a purchase.
So you don't Understand how a differential works? The VCU is just a diff lock, nothing to do with transmitting power to the the front or rear axles which is done by the centre differential.

Ok carry on you know best. Let us know how you get on with your mod. :p:D
 
Last edited:
Here is the same picture I posted before:-
attachment.php

The outer case of the VCU connects to the large shaft splines and provides the drive to the front prop via the casing, the inner part of the VCU connects to the axial inner shaft from the rear prop drive, when the two shafts rotate at different speeds due to wheel slip, the VCU progressively locks. Removing the fluid from the VCU simply prevents it locking when the shaft speeds are different.

Remember, information is king:p:D:D:D
 

Attachments

  • TRANSFER BOX.jpg
    TRANSFER BOX.jpg
    253 KB · Views: 187
All my previous 4 x 4's had had open centre diffs with a centre diff lock, I don't remember ever having to use the centre diff lock, but then I don't do any serious off road stuff.

If you have no diff lock and you get stuck it would allow the axle without traction to get all the power there would effectively be no drive to the none slipping axle. If one wheel on the driven axle has no traction all the power will go through that wheel. The centre diff is just the same as a diff in an axle were if one wheel has no traction no power is sent to the wheel with traction. Without a centre diff lock the front wheels or rear wheels can be driven independent of each other. You can have the rear wheels spinning without driving the front ones. So it is possible to have one wheel spinning on the driven axle which means you are going nowhere. Understanding information is king. :p:p:D:D
 
Last edited:
If you have no diff lock and you get stuck it would allow the axle without traction to get all the power there would effectively be no drive to the none slipping axle. If one wheel on the driven axle has no traction all the power will go through that wheel. The centre diff is just the same as a diff in an axle were if one wheel has no traction no power is sent to the wheel with traction. Without a centre diff lock the front wheels or rear wheels can be driven independent of each other. You can have the rear wheels spinning without driving the front ones. So it is possible to have one wheel spinning on the driven axle which means you are going nowhere. Understanding information is king. :p:p:D:D
Tell me something I don't know. If understanding information is King, it's a shame you don't understand. With 4 wheel TC any spinning wheel is checked with or without the VCU.:rolleyes::rolleyes::rolleyes:
 
Tell me something I don't know. If understanding information is King, it's a shame you don't understand. With 4 wheel TC any spinning wheel is checked with or without the VCU.:rolleyes::rolleyes::rolleyes:

Yeah but without the VCU in the P38 centre diff there won't be any spinning wheels. Think you had better look at the diagram you posted and understand why that would be so.
 
Yeah but without the VCU in the P38 centre diff there won't be any spinning wheels. Think you had better look at the diagram you posted and understand why that would be so.
Gosh, you really don't understand how a diff works, or maybe you need specsavers.
With an empty VCU, the case still transmits power to the front prop, the rear drive is always connected.
 
I found the explanation over the page on how the VCU works more help.

With little differences in speed the jelly stays liquid and the VCU doesn't do anything. When the front and rear shafts spinning speeds are a lot different it heats up and locks solid. So if you could get the jelly out it would never lock. Think that was Datatek's idea.

Of course, as Wammers pointed out, if you hit some mud and you're going to have fun!

Personally I still like the idea of a proper difflock.
 
I found the explanation over the page on how the VCU works more help.

With little differences in speed the jelly stays liquid and the VCU doesn't do anything. When the front and rear shafts spinning speeds are a lot different it heats up and locks solid. So if you could get the jelly out it would never lock. Think that was Datatek's idea.

Of course, as Wammers pointed out, if you hit some mud and you're going to have fun!

Personally I still like the idea of a proper difflock.

Remember the lad with the Bees, that was more than likely his problem. No jelly to transmit the welly. :D
 
Back
Top