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Hi All, I have an Ulster Rep with Semi-Girlings. The right front had loose wheel studs which I replaced with spares from one of the cherished providers. Unfortunately, the rivet heads were too large and had to be turned down and then ground down flat so the inner and outer plates could mate properly. The bearings are not tight but turn freely. On the N/S, the hub turns easily and continues to spin. Upon removal, the inner bearing allows the inner plate to cock about 1/16 of an inch which would translate to a good deal of play at the wheel. As I am new to Austin Sevens, it would seem that this is unacceptable. Tapered bearings on my old Minis would allow spin but no slop. Do I need to replace the bearings on the nearside? If so, what is the best way to remove the inner ball bearing from the inner plate? I can't wrap my head around how to drive the bearing out and it seems a bearing puller is not going to help. Any advice is much appreciated.
Erich in Mukilteo
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The outer bearing should be a reasonable fit in the housing. The inner bearing should be a good radial fit in both halves, although can get away with one. The assembled bearing should be clamped axially by the two halves. Whether or not a sealed bearing is fitted, if ithe large steel washer is ommitted, or too thick gaskets used the bearing will not be clamped. Then work loose axially and radially and difficult to remedy (although heavy centre dotting plus a good clamp fit often suffices. if not water damaged bearings normally barely wear so when all assembled and after some settling should be at most just perceptible play due the bearings (as distict from k pin). Some tolerances of ball race allow considerable tilt, but this alone has no effect when all bearings assembled. The inner bearing is seldom really tight unless glued. If it has no obvious radial paly and is smooth would leave alone. The fact that it wont drop out easily probably a good sign. Just bumping onto a couple of wooden blocks is often enough to make it fall it out. It is not ideal to push on the rotating inner ring of the bearing but will tolerate reasonable pressure.if someone got carried away with Loctite could be difficult.
The stud rivets must clear everything on the backplate.
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Thank you, Bob. It is the inner bearing that has the slop...radial play 1/16 inch at the edge of the plate. Seems too much to me. The outer one is less and I could possibly just replace that. Hard to know as a neophyte what is acceptable.
Erich in Mukilteo
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1/16 tilt does seem generous unless also loose on the axle. But tilt involves axial clearance and it is only pure radial celarance which afects wheel tilt all assembled. Assemble fully and see what then. The nut does not have to be very tight.
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Tony, so 1/16 inch of play and the edge of the inner bearing carrier is acceptable? It is odd because the bearing on the o/s has zero play but isn't binding and turns easily but doesn't spin wildly like the n/s. The n/s hub, even without the wheel or brake drum, spins wildly and easily when I give it a good turn.
Erich in Mukilteo
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Location: Bristol
Eric if the hub nut has been over tightened it can crush the bearing spacer pinching up the clearance, or not tight enough the opposite. Terry.
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New ball races come in a range of grades and tolerances and some have deliberate generous axial clearance for the many applications where shfts wobble to some degree (gearbox s, rear hubs etc) . The radial clearance determines play in most applications although not easy to assess. I am not saying it is not worn but it may not be. The bearings are very generously sized.
Everyone should be familar with the diagram Tony provided. The washer alongside the felt is discernible. Note the outer race is not externally clamped so wheel play on initial assembly may increase slightly after a little running. On many BMC cars angular contact races are used and the length of the spacer and whether or not over crushed is critical. AC races must not be used in the Seven!
(The Manual for my 1964 Minx states and emphasises .002 to .007 end float for the hubs. I have always maintained this and as the bearings have doen 200,000 seems to have worked. But, combined with wear on the axle, causes apoplexy when going for a wof. So rather than argue I overtighten and slacken before and after every tedious and expensive 6 month ritual. Repeat wrangles over tolerances for older vehicles is a major disincentive to run an older car here, although registration is very cheap)
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24-02-2022, 11:00 PM
(This post was last modified: 25-02-2022, 04:12 PM by Erich.)
Thank you all for the responses. At this point, I have decided to reassemble both hubs as they are. The o/s one had to come apart because of loose wheel studs. The bearings are an Indian made brand, turn easily but no play at all. The n/s ones are Hoffman brand made in England and I now believe the minimal play with these is a designed in tolerance, as the bearings appear to be in good shape. I guess when I see one wheel or another part company with the hub, I'll know what the problem was. ;-)
Erich in Mukilteo
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Location: Malvern, Victoria, Australia
Aha! The Indian bearings could be made from anything and have any old internal clearance.
Always buy reputable brands - and not Chinese copies !
