I just did the install on the gear and end cap. Thank you very much for a very much needed set of components, and for the quick response.
Some installation notes you may want to consider adding to cap_gear_installation.pdf:
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1. Prior to unplugging power from the seat, raise its height to maximum.
2. Removing the allen bolts from both the left and right sides, not just the side being repaired, makes the job much easier.
3. Removing the old gear. I did not heat it and it cracked when it came off. That seems ok (and less work than heating

).
4. Pressing the new one on had me nervous but turned out to be easier than I expected. Just be careful to line everything up and keep it lined up until the first light blow gets the gear started on the shaft.
5. Before completing the reassembly, it's important to line up the jack screws. Even if careful in disassembly chances are, especially if a gear was stripped, they are no longer aligned. To line them up:
a. Prior to putting the nut on the end of the jack screw, the plastic piece at the other end, and prior to final tightening of the two 12mm bolts that hold the jack screw in place (also, it helps if the seat is upside down for this).
b. Plug in the seat and use the motor to move the seat close to one limit or the other, but not all the way. Leave a few threads showing.
c. It will be apparent if they are not aligned. For example: one may have 3 threads showing and the other 4.
d. Remove the two 12mm bolts, lift off the jack screw, adjust it, reinsert it.
e. Visually verify that both are now lined up.
f. Give a final test that it arrives at its destination on both sides at the same time.
g. Run it all the way to the other end and ensure that all is well there as well. For example, there might be hair or other junk wrapped around a jack screw, limiting full travel.
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One other item of note, regarding the rubber washers inside the housing: Mine differed from the example in that both were on the same side of the gear. Just wondering if others were like this?