King pins or wheel bearings

[John Mason]

Advice sought from members more knowledgable than me.  How can you tell if play in the front wheels is caused by worn bearings or kingpins. Also if it is wheel bearings can they be adjusted.

John Mason

[Ruairidh Dunford]

Wheel bearing play shows up with movement evident between the brake drum and the dust plate.

Play associated with the king pins is more often a worn axle eye and shows up with movement evident between the stub axle and the axle beam.

[Parazine]

Put the handbrake on, hard. That will eliminate the wheel bearings by forcing the brake shoes onto the drum. What's left is play in the kingpin or play between the pin and the axle eye, the latter especially on later, heavier thirties cars. There's no adjustment I'm afraid, if the bearings are worn, replace 'em!

[AustinWood]

Wheel bearings can't be adjusted. If there is play they are either worn or loose in the housing.

[Tony Press]

The front wheel bearings are plain ball bearings with normal internal clearance so will always have a little movement even from new.

They are rather over-sized for the job so wear is unusual, but the inner bearing is sometimes loose in the hub assembly. 

If you are replacing them use double sealed bearings.

[Bob Culver]

Agreed the bearings are very generously sized and should last forever. Monstrous by modern standards.
The outer ring of the inner race shoud not only be a very snug fit in the housing but should be lightly pinched when all is assembled. If the gasket is too thick and/or the concave steel seal washer omitted the race will not be gripped and work loose. I dont know if hubs vary much but all can be checked with a vernier calliper depth gauge. Ideally should be tight in both hub halves but if well clamped one will do. Some resort to Loctite but many hubs have been distorted even without that complication. Perhaps just treat one half.
Many attempt to assess bearings by tilt but this can vary markedly. Radial clearance is the real factor, not easy to assess.
Normally races are only considered failed when tracks or balls are pitted.

[John Mason]

Thank you all for your advice and information. I will address this problem with my car but not as yet I will need the assistance of my son who unfortunately is keeping away from me due to the fact I am a a person at risk from this bl***dy virus.

John Mason

[Dave Mann]

Tony's comment "They are rather over-sized for the job." doesn't just apply to the hub bearings. Some years ago our modern with a turbo charged 2 litre diesel engine suffered a clutch release bearing failure. The garage phoned me to tell me they'd dismantled it and did I want to see it. I went with a clean Seven clutch release bearing in my pocket. and they showed me the wreckage, then I showed them a proper man sized bearing, it was over twice the size. The fitters couldn't believe it was for my Seven which they knew well after it had towed the modern in on two occasions.

[Tony Press]

These 'oversized' bearings need to be taken in context. 

The Austin 7 was quite advanced being fitted with rolling element bearings in an era where the techniques of bearing design were being developed.

The early Swedish bearings (SKF) were made using their remarkably clean Swedish steel which gave longer bearing fatigue life, this advantage now largely overcome by the use of vacuum melted steel by most reputable manufacturers.

In the 20's bearings were selected to give a calculated running life based on current criteria- with the design and material improvements modern bearings can be made smaller for a similar fatigue life. 

The design of machine elements has improved as well- the early bearings were sized to fit the shaft which would now be smaller for the same strength.

Given modern vehicles are designed for a much shorter life than Austins used it will be very surprising if any are still running in 90+ years !