[Mgs] Front Wheel bearings 70B

[Paul Hunt]

Was it the rollers or the inner ring they run on that was marked?  If the 
latter it could have been because the inner ring was spinning on the axle 
shaft, but then the nut would have been loose when the split-pin was 
removed.  Insufficient shims causing lack of free play or end-float would 
affect both bearings in the set equally.

There should have been a series of shims between the spacer and the outer 
bearing.  A thick one of 30 thou, then a series of thinner ones at 3, 5 and 
10 thou which set the gap.  Reassemble dry (easier to judge when there is 
end-float or not) and don't fit the oil seal, with no shims tighten the nut 
to 40 ft lb or until they start to bind to seat the bearings in the hub, 
then start setting the shims.  By juggling combinations 3, 5 and 10 thou you 
can get pretty much any thickness in one thou steps from 8 thou up, and you 
should need more than that.  What you are looking for is one set that gives 
just perceptible play, and another set one thou smaller that doesn't.  The 
lower set plus a 3 thou will give you the correct 2 to 4 thou end-float. 
The shims are not marked, but by using one shim to bend another one you can 
tell which is which.

When you have the right combination remove the races and pack them by 
pressing grease in from one side only until it oozes out the other end of 
the rollers. Patience is required, don't be tempted to speed things up by 
pressing it in from both sides or you will trap air and have insufficient 
grease.  The smaller outer bearing is more important, centrifugal force 
tends to throw grease into the larger inner bearing.  With the races 
replaced fit the oil seal, groove and lip facing the bearing, lip greased, 
with the groove packed with grease.  Don't pack the space between the 
bearings with grease.  Refit the hub, spacer, shims, outer race, sealing 
washer and nut.  Tighten the nut to a minimum of 40 ft lb, then to the next 
split-pin hole (should be two in the spindle), which should be before 70 ft 
lb, and insert a split-pin.  This *shouldn't* remove the end float.  Make 
sure the play you are feeling is in the hub bearings and not anywhere else 
like the king-pin bearings etc.

PaulH.

----- Original Message ----- 
> I pulled the right front wheel and disassembled the bearings due to it 
> having
> too much play on my 70B. The outside bearing (smaller of the 2 ) was 
> charred
> like it might have been over tightened. I'm replacing it with a new set of
> bearings. There was a really thin shim that was stuck on the cone shaped
> spacer. Not sure what size. Any hints or tips welcome.