Replacing the gas cylinder on a Stealth chair takes about 20 minutes with basic tools and restores the chair's full height range.

1. 1

   Lay the chair on its side

   Put the chair on its side on the floor or a table so the base and cylinder are accessible and the seat is protected.

2. 2

   Separate the base from the cylinder

   Grip the cylinder with a pipe wrench and tap the pipe wrench with the rubber mallet. The taper fit is friction only, so it releases with increasing torque. Please note, channel locks will slip before they can get enough grip to remove the cylinder. The use of a pipe wrench is important.

3. 3

   Free the cylinder from the wheel base.

   Tap the wheel base with a mallet while holding the cylinder, rotating hits circling around each leg of the base. If this is too difficult, set the wheel base upside down (piston facing the floor) on a table and strike the bottom of the cylinder out of the wheel base. Wear proper PPE and take safety precautions.

4. 4

   Seat the new cylinder

   Drop the new cylinder into the wheel base, lower the seat mechanism onto it, and press down firmly. Sitting in the chair sets the taper.

5. 5

   Test the full height range

   Raise and lower the chair through its full travel a few times to confirm the lever engages and the chair holds height under load.

Worn bushings cause a knock in the backrest. Replacing them takes about 15 minutes and removes the noise.

1. 1

   Identify a broken bushing

   If one or more bushings have broken, it can cause the chair to tip. This means it is time to replace all 4 bushings.

2. 2

   Unscrew the old bushings

   Unscrew the bushing nuts on the bottom side of your chair with a 13mm box wrench or an allen key for older chairs. Then unscrew bushings from the bottom of the seat.

3. 3

   Screw new bushings in

   Screw the new bushings into the bottom of your seat and set the seat back on the mechanism with the bushing threads poking through the bushing holes.

4. 4

   Reinstall Seat

   Reinstall washers, lock washers and 13mm nuts back onto the bushings.

A backrest with play in it is usually loose mounting hardware, which takes about 10 minutes to correct.

1. 1

   Check the backrest hardware

   Most backrest movement traces back to loosened mounting hardware rather than a failed part. Locate the bolts where the backrest meets the seat frame.

2. 2

   Tighten in a cross pattern

   Snug the bolts in a cross pattern so the backrest seats evenly against the frame. Firm is enough — over-torquing strips the thread. When reinstalling the spring, it always goes on the bottom "pin" of your backrest bracket.

3. 3

   Re-test under load

   Sit in the chair and lean back through the full range. If play remains after tightening, you may need a new backrest bracket — contact us with your model number.