Mike,
Sorry for the confusion. I had used "overloading" and "crush"
in two different places.
You are correct the shims are NOT used for preloading the bearing,
like the old taper bearings were used. But the shims are there for
a reason.
The shims are used to allow a NEGATIVE clearance of a few
thousands. Like I descibed, it prevents the bearing from sliding
back and forth in the housing. Simple to measure the depth of
the housing recess, and calculate the bearing thickenss. Adjust
the shims allow for negative clearance (the rear axle bearing is
"squeezed" between the axle housing recess and backing plate).
If the shims were not needed, you wouldn't have found them
on the later Datsun/Nissan rear axles, too.
Cheers,
Tom Walter
Austin, TX
>From Thomas Walter
>The shims are there to prevent "overloading" the bearing.
>Most likely were removed from years ago, or that axle just
>happened to have a dead on clearance (rare, but not impossible).
>>From: "Mike Kerr" <mikekerr@innercite.com>
>
>>tom the shims where left over from the truck/sedan axles where they had
>>tapered roller bearings instead of ball bearing that the roadster has. The
>>tapered rollers have a preload to them and that is what the shims where for.
>>on the roadster it didn't need the load careering of the tapered rollers, so
>>they used ball bearings instead , a simpler and cheaper way to go. the
>>shims do act as a kind of gasket .
[original part of the message from Thomas]
>Having said that, I can not recall the proper about of "crush"
>that is imposed on the SIDE of the bearing in the housing. You
>do not want the bearing to slide back and forth in the, hence a
>little bit of negative clearance. 0.005 seems like it would be
>fine.
[snipped rest of it]
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