Wheel Bearings


Manufacturers do not want to make replacement from other sources that easy, regularly mixing two standard bearings into one assembly, although I doubt that Bristols went this far.

Take off one complete set of bearings (2 sets of bearings per hub; the inner bearing is usually larger than the outer; both will be tapered roller bearings) and find yourself a local  machine tool service company.   Take your bearings in and they will measure them while you wait (about 5 minutes).  There are 3 grades of bearings used classed  A, B and C.  The tolerances in manufacture are, of course, extremely tight so they employ an automatic grading system – A being the best and that’s what you want.  C are the poorest and probably go into washing machines and the like.   I think the classification system may have changed possibly 1 – 3.  If the numbers on the bearings are visible you should be able to quote these to any bearing company and avoid the need to go to a machine tool service company.

Valid at time of writing in October 2016:

There are a number of good bearing suppliers eg Seager Bearings, Kings Heath, Birmingham (0121 444 5391) who will supply at trade prices.

Door boot seals & draught excluder

Please find contact details of the Furflex/draught excluder supplier:-

William Marston Ltd
70 Fazeley Street
B5 5RD

Tel: 0044 121 643 0852 or 0044 121 643 0372

email: info@williammarstonltd.co.uk
website: http://www.williammarstonltd.co.uk

The boot seals can possibly be obtained from:-

Phoenix Supplies
Unit c1a Langlands Business Park
Devon EX15 3D4
Contacts: Nigel or Kaye Coles

Tel: 0044 1884 849294

email: phoenixsupplies@hotmail.com
website: http://www.phoenixclassictrim.com

or –

Woolies (I & C Woolstenholmes Ltd)
Whitley Way
Northfields Industrial Estate
Market Deeping

Tel: 01778 347347

email@ info@woolies-trim.co.uk
website: http://www.woolies-trim.co.uk

Both of these companies carry a large range of extruded sections and just may be able to help with boot and door sections.

How shock absorbers work

(Extracted by K. Lutz)

Shock absorbers don’t really absorb shock, they dampen it, hence they are often referred to as dampers. Why is this important for you to know? To improve ride quality. Basically put, a shock absorbers sole purpose is to dampen the compression and rebound of any suspension system by controlling the speed at which a suspension cycles. Without them, your car would continue to bounce up and down until the kinetic energy is finally dissipated from the suspension’s springs (e.g. leaf springs, coil springs, torsion bar, etc.) and sea sickness may follow.

Now let’s think about the law of conservation of energy. With this law in mind, shocks will perform two functions. The first function is to slow the suspension’s cycling of compressing or rebounding. Secondly, since energy can’t be destroyed, the shock transforms the kinetic energy into heat as it dampens the “bouncing” of the springs. That’s it. That’s what a shock does.

Or otherwise put – in a vehicle, it reduces the effect of travelling over rough ground, leading to improved ride quality, and increase in comfort due to substantially reduced amplitude of disturbances. Without shock absorbers, the vehicle would have a bouncing ride, as energy is stored in the spring and then released to the vehicle, possibly exceeding the allowed range of suspension movement. Control of excessive suspension movement without shock absorption requires stiffer (higher rate) springs, which would in turn give a harsh ride.

Shock absorbers allow the use of soft (lower rate) springs while controlling the rate of suspension movement in response to bumps. They also, along with “bounce” in your tyres, dampen the motion of the unsprung weight up and down on the springiness of the tyre. Since the tyre is not as soft as the springs, effective wheel bounce damping may require stiffer shocks than would be ideal for the vehicle motion alone.

Spring-based shock absorbers commonly use coil springs or leaf springs, though torsion bars can be used in torsional shocks as well. Ideal springs alone, however, are not shock absorbers as springs only store and do not dissipate or absorb energy. Vehicles typically employ both springs or torsion bars as well as hydraulic shock absorbers. In this combination, “shock absorber” is reserved specifically for the hydraulic piston that absorbs and dissipates vibration. Below are some images which illustrate these principles, and the technical features of dampers.