Senior moment time. I am sure on the last 7 I had there was a very small amount of play in the front hubs with the wheels off and pulling the disks hard. When I took the current car ones apart the nuts were more than finger tight and no play at all. I have not dismantled this car previously and as it came from Caterham, left it for a year before fiddling. It has unknown 20 year history but is immaculate and has been maintained by garages in the past.

I have reassembled the hubs after greasing, taking the nuts up to finger tight then backing them off a fraction before putting the locking pin in and yep the small amount of play I had on my first seven is replicated.

I need a confidence check that having the play in the hubs is correct. I thought it had to be there to allow for expansion, at least on every other car and tailor I have had with similar taper bearings there has always been play. I can't find anything in an old build manual to confirm my thinking.

At the back end - I have the older style anti role bar (ARB) sited roughly parallel to the drive shaft rather than low down. Anyway the ARB has lateral play in the cotton real bushes so I am guessing they are probably in need of replacement in the near future. Not having done this previously can someone confirm they are fitted by sliding them over the ARB ends as I cannot see another way of fitting them.

Thanks

I run my hubs with 'slight-to-none' free-play.
Always have done.
And I test with the wheel on, twisting top/bottom to check the free-play amount.

Can't comment on the real ARB, as I don't have one...

Thanks Eugene. Perhaps the original slight tightness was not incorrect after all then? The only reason I investigated was due to an occasional squeak on the left front that did not appear to be brake related. I think I will leave the minuscule amount of play. Job was worth doing in any case as there was minimal grease on the drivers side.

There are various opinions about preload but backing it off and leaving a little play is an outdated practice that will only shorten bearing life and make setting reliable geometry impossible. Modern bearings are designed to run with a preload. The reason is that it distributes the load across more than one roller and stiffens the whole assembly. Typically you want 8 NM on the nut while you rotate it and then backing it off to the nearest hole.

Some SKF info here http://www.skf.com/uk/products/bearings-units-housings/roller-bearings/principles/des ign-considerations/selecting-clearance-preload/bearing-preload/effects-bearing-prelao d/index.html

DCL
That is interesting thanks. What you describe is probably how mine were set before I took them apart in reality. Certainly it is true that they do make slightly more noise with the loser setting when rotated on the axle stands. I must admit I thought that preloading taper roller bearings was a system specific approach but can understand the more even loading described.

Given that I have no idea what age the bearings are, could be anything between 20 years and 1 year and the design is 50 years old I wonder at what point the revised practice takes effect. i.e . the old practice may be outdated but is it appropriate to apply modern thinking to ages old system as I imagine modern bearing materials are far better than their predecessors?

Best wishes

I would consider 20 years as modern - you're really looking at pre 1950's before clearance were routinely specified. But engineering practices are passed from generation to generation and old methods stick around. It's down to improved greases as much as anything, but bearing materials are also significantly better today (if you avoid the cheap stuff). On the other hand, a slight clearance only reduces life slightly, so many people like to play safe, but the optimum performance requires the correct preload.