quote:
Originally posted by jbottini
Peter,
I'm planning on evaluating brakes this weekend...your observation is in line with mine. As to rear wheel bearings, I need to re-pack, not replace. your experience there could be helpful. do you have more details of that procedure than are on the "rebuilding" site/
Jim
Jim,
here comes a short description of what I did. It's not professional but it worked with the tools I had at home.
The original bearing spacer were made of normal construction steal. That
was to mild. Now, my turner made me spacer using C45 steel. But I guess
this is a german DIN standard. It's an non-alloyed high-grade steel with
a carbon content of 0,45 mass percentage. That should be ok.
So, you need a bearing spacer with a thickness that is a little bit too
big so you can grinding it to the perfect thickness. Of course the
thickness of the two different spacer (left and right) will be different
in general. I think a thickness of 17mm should be ok for a starting
point. The I.D. should be s.t. the spacer has no tolerance on the hub
but you should be able to remove it by hand. The O.D. was 1 7/8".
Step 1: put all the things together (with grease) but
without the
spacer and
dont use the bolt for the rear drive flange. Press the
flange simply by hand as far as you can but without big power. The roles
of the bearing shouldn't be pressed strongly to the hub carrier. Now,
put the assembled hub into a wheel and measure the torque you need to
start turning the hub. You should use a spring scale for that job.
Please look at the following picture what I have in mind:
The idea behind this task is to get a reference value for the torque you
need to turn the wheel when there is no (or nearly) no pressure on the
bearing.
Step 2: put all together
with the spacer and the
bolt for the rear
drive flange and torque it nearly to it's final specification. The hub
carrier should have a certain tolerance on the hub because the spacer is
to thick s.t. the bearing rolls are pressed to the hub carrier. If you
have no tolerance the initial spacer was to small. How you you test the
tolerance? Unfortunately, I don't have a picture of that and I don't
want to remove the hub carrier from my car. I mounted a leverage of ca.
60cm at the hub carrier and put it into the wheel and torqued the wheel
nut. Now, if you fix the wheel you have the power by the leverage to
check the tolerance of the hub carrier wrt. the hub.
Step 3: remove the bearing spacer and grinding let's say 0,003". I used
sandpaper for that. If you do it by hand you will probably slope it. I
used this simple but effective way:
In order to measure whether you really has only 0,003" removed to should
use a micrometer. If you don't have one you get it for some euros at ebay.
Step 4: repeat step 2 and step 3 until there is no tolerance of the hub
carrier to its hub. (I guees you will repeat this 5, 10 or 15 times).
Please check each time the torque you need to turn the hub carrier and
compare it with your reference value from step 1. It shouldn't increase
too much. You are finished if there is no tolerance and the wheel turns
easily.
Step 5: repeat everything for the other side