To: SABMAG@MITVMA.MIT.EDU <SABMAG@MITVMA.MIT.EDU>
Subject: Beware - installing wheel bearings
Date: 8. May 1998 

Beware when installing front wheel bearings:

The following is a description of a problem I encountered while installing
front wheel bearings on my `85 V65 Magna.

Prior to installation, I stored the bearings in a freezer for about 10
hours... hoping to shrink `em a bit for easier installation.  I made sure
everything was clean, and I lightly lubricated the o.d. of the bearings.  For
a bearing driver, I found a piece of pipe of perfect diameter with a good
thick flat square edge.  The driver gripped the outer race of the bearing
only.  I started with the right side bearing, tapped carefully and evenly
about the driver, and the bearing went in ok.  It needed a lot more effort
than I would have thought, or liked, but it went in.  (correct oem Honda
bearings)  I then flipped the wheel over, inserted the "distance collar"
against the backside of the installed bearing, and proceded to install the
other bearing.  (for those unfamiliar, the "distance collar" is a spacer tube
that gets wedged inside the hub between the two bearings... it touches the
inner race of the bearings).  OK, I then drove in the second bearing using the
driver... kept on pounding until the outer race was fully seated in the hub.

I put the axle in and tried to spin the wheel, but it did not want to turn.
The inner races of the bearings were binding badly - much resistance.  What
the heck???  After studying, I found that my distance collar is a bit too
long, so that when the outer races of the bearings are fully seated in the hub
of the wheel, the collar gets wedged too tightly between the inner races of
the bearings.  This problem probably would have been reduced or avoided if I
were using a bearing driver that was perfectly flat, one which exerted force
on the entire bearing, both outer AND inner race.

Of course, I was now unhappy because I knew that I might have damaged the
bearings a bit.  Anyhow, I was able to knock one bearing "out" very slightly,
just enough to relieve the pressure against the distance collar.  Once this
was done, everything turned effortlessly and smoothly.  At this point, careful
inspection showed that the bearings were now seated at least 99%, and the
distance collar still wedged between the bearings, but not enough to cause
binding.  Seems to turn fine.  If I was a super perfectionist, I'd throw out
these brand new bearings and do it all over again, just in case the new
bearings got hurt in this episode.  But, everything seems perfect now, so I'll
take a chance.  If something is not right, I'm sure I'll feel it or hear it
well before it fails.  And the front wheel will be off again for a tire in
another 10k or so anyway.

Lesson learned... when driving front (and perhaps rear also) wheel bearings,
use a flat driver that supports both outer and inner races evenly.  If only an
outside race driver (such as a socket or pipe) is available, be sure to drive
slow near the end of the travel, testing for binding of the inner race.  Once
the distance collar is just slightly gripped between the two bearings, STOP
driving.  Even with a flat driver, to be safe, test for binding before all the
way in anyway.  In any case, everything should turn free and smooth.  Another
option... carefully measure everything beforehand, and shorten the collar if
necessary in order to obtain a perfect fit.  Something to keep in mind when
changing bearings.


Dave Miranda