On Thu, 21 Feb 2008 14:28:28 -0700, Richard A Jones <jones@COLORADO.EDU>
wrote:

>I'm tracking a vibration rattle in a seat and so I looked
>at ETKA.  It shows two "guide pieces" (251 881 213) that
>go in the rails.  I remember years ago finding some white
>plastic pieces like this breaking apart in my '81.  So
>I pulled them out and forgot about it.
>
>Should I replace them?  Does it make the seat slide easier?
>
>For my Syncro Westy, I looked at the swivel and found only
>two of the "upper guide pieces" (251 881 319), and
>no "lower guide pieces" (251 881 320).  Or are the lower
>ones underneath the swivel, so I didn't see them.  I should
>have 4 of each per seat, correct?  Should I just replace
>them all while I'm at it?
>
>Thanks,
>Richard

Richard,
It is definitely worth replacing these guide strips in the seat tracks.
They prevent metal-on-metal contact between the seat rails and the tracks
in the swivel in which they slide (or, for others without seat swivels, in
the corresponding tracks welded to the base pedestal).  Since the sliding
mechanism was designed to have these guide pieces in place, and they do act
as a bushing, you will indeed have excessive play in the slides without
them, very possibly leading to the rattle you mention.

These guide pieces simply slide into the track from the front, and lighly
snap into place by means of a raised button encountering a corresponding
hole, however, expect to spend much more time thoroughly removing the old
grease/dirt amalgamation from both the seat rails and the tracks first. The
interior of the hollow, slotted, tube portion of the track can be cleaned
by using a stiff steel wire, looped around a small piece of cloth soaked in
degreaser, and pulled through the tube as many times as needed. This
cleaning is important, because the presence of the dirt in the grease is
likely what ground down the plastic guide pieces in the first place. After
the cleaning, and installation of the new guide pieces, I find a spray-on,
lithium grease the easiest way to lubricate the slide mechanism (be careful
to avoid overspray onto the carpet).  This is an area where more grease is
not better, as it will only serve to catch more dirt sooner; apply just
enough to get a film on the plastic guides.

As for the bushings for the swivels themselves, you are correct, there are
four upper guide pieces, one in each quadrant on the bottom of the round
ring that bolts down to capture the swiveling seat base, and  there are
also four lower guide pieces, one in each quadrant of the pedestal under
the swiveling seat base.  Both the upper and lower pieces snap into their
respective holes; all eight are needed for the smoothest operation
possible, again lightly lubricated.

Upon reassembly: if the round ring that captures the seat swivel was
secured with nuts and lock washers, consider substituting metric Nylok
nuts; these can be tightened equally, and then backed off a quarter or half
a turn each, or more as necessary, to provide for easy swivelling of the
seat, without the nuts coming loose, as could a lock washer/nut combination.

This is easy work, and well rewarded with seats that slide and swivel with
ease.

Bill