Robert,
Thank's for sharing your views with me.
>Whoa there! I would like to hear some dialog on those lousy shims. Three cars
>and several years ago I read carefully the instructions on those shims that
should
>be fitted between the outer race and the conical spacer. And I read all the
>details on measuring the gap --- and I decided it was all a bunch of hooey.
Let me share some ponderings with you...............
I too have read, digested and followed those directions from the shop manual.
I followed them, to the letter! Even got myself a dial gauge and spent
almost a full day swapping shims. Even got some new ones mic'ed em up and
selected the exact ones for the job. I could never get the end float just
right on one side. I fought the thing for hours! Finally I swapped the
castled nut and hey presto it was OK, I finally had the 4 thou end float.
Having got it RIGHT, I was hard pressed to believe this was really
necessary, I mean 4 thou! Was I to go through this misery again and again in
the future? What about all the machining tolerances can the bearings be that
critical? I don't believe they are today, I don't believe the US car makers
even use a spacer between the bearings do they?.
My personal belief is that those darned BRITS (I am one also), were working
to a perfection point that is beyond reasonable limits. Those tapered
bearings, I doubt, needed to be set up that precisely, perhaps they did at
one time, who knows.
I have worked on a 79 B that even had the spacers removed from the hubs I
never knew it, I was not aware of any handling problems.
Why would you need that spacer anyway? The hub is designed so that the
bearing cages seat in the casting thus defining the center lines of the two
bearing surfaces with one another. The rollers themselves take the full
thrust and provide the rolling surface interface with the grease. Like you
suggested, seat the bearing, back the nut off a hair, put in the pin and
away you go much easier and far quicker. Providing a spacer and shims does
afford a RIGID assembly alignment and perhaps extends bearing life. If they
were hundreds of dollars new, I could understand the need, but I am only a
lowly engineer what do I know I didn't design it. I just follow the
maintenance instructions!
>
>I think that trying to measure .004 play is impossible because:
>1) Once the new assembly is packed with grease you won't feel any and
>2) what you do feel is (acceptable) play in the kingpin.
I do think it is possible to make the determination of where the movement
is, king pin or axle, but the assembly should be dry, free from grease, to
make that judgement.
>
>So what's the scoop? Why would just the British have the shims and are they
really
>important with modern bearings? If someone want's to tell me the dire
consequences
>of losing the shims, I guess I'd like to know when they might be showing
up. They
>haven't in 30,000+ miles.
Was there a possibility that the bearing manufacturing and hub manufacturing
tolerances could not be held well enough by the various suppliers and so it
is was deemed necessary to provide that fixed datum afforded by the spacer
and shim arrangement? I have no idea what the 60's manufacturing goals were,
labor was probably cheap and materials at a more cost conscious level?
I do know I have never had a wheel bearing go out! I have however, replaced
bearings as a preventive measure and a means of getting to know my machine
more intimately. Besides I like to play with tools and get my hands dirty!
Comments from the net, from the more knowledgable?
John Bartholomew. San Jose CA.
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