rear hub spacers/shims

[GigGleR]

we are currently in the process of replacing the rotoflex rear driveshafts on our 1970 vitesse mk2 convertible to uprated sliding spline jobs from Kingston Sportscars. The problem we've got is trying to measure for the spacers/shims that fit between the bearing the vertical link and the hub.

Originally this would have been done with a specialist tool from Churchill (an s325 to be exact if that helps anyone) this, of course, is impossible to get hold of anymore so does anyone have any ides on how we can measure for these spacers?

I do hope someone can help as this is holding the job up at the moment  :(

[Tim Bancroft]

Send them to Dave Pearson at Canleys he has the correct tool?

[Nick Jones]

Hi,

Presume you are talking about shimming the  hub bearing end-float.  This is a right royal pain with several bits of design foolishness working against you.  You do also need to have some decent measuring equipment although the churchill tool is not essential.  DTI to measure the end float and a micrometer (or at least a decent vernier) to measure the shims.

Hopefully you kept the shims that were fitted when the hub was dismantled.  Good starting point is to re-assemble with these shims although with new bearings and maybe even a new outer shaft (not sure what the sliding spline conversion involves) there is no reason at all why this should be right.  Take care when doing this that the bearing does not go tight as you do up the hub nut - this proves you need more shims and fully tightening in this condition could damage the bearings.

Once you've done this, you should measure the hub end float with a DTI and from this you can work out what shims you need to add or remove to get to the correct end float.  And yes, this does mean taking it apart again, with a puller, great isn't it!  Think the churchill tool is meant to make it possible to do without dismantling again, but I've never seen one.

I have heard it said 'rule of thumb' that end float is correct if you can just feel a hint of play at the wheel rim with it all fitted up to the car.  This does tally with my experience BUT if you have rotoflexes fitted they preload the bearing and no play can be felt.  However, on a car with sliding spline shafts (or CV conversion as mine) this may have some use as a check. Not really recommended though.

This link may be interesting too: http://www.geocities.com/spitfiregt6/rrbrng.html

Hope this is helpful

Nick

Edit:  If you don't have the measuring equipment or the patience - Tim already gave you the best answer!

[Tim Bancroft]

I have built my hubs up twice before, once using a company in West London, the second time using Canleys. I would use Canleys again.
As Nick says it is a painful job, also if not done correctly can lead to catastrophic half shaft failure. This happened to a good buddy of mine resulting in a 70mph spin- he's lucky to be alive!

[GigGleR]

after much messing about with hubs and vernier calipers and depth gauges we have foiund that we need to get some 0.020" shims. But we also found after dismantling the hubs that the idiot that rebuilt this vitesse before we had it didn't bother putting any shims in and just had the spacers!  :-/

I think it was more luck than judgement that we got the vitesse back on the 10cr as almost all of the splines had stripped off the passenger side hub and shaft!!  :'(