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C23/E90 Dampener Upgrade Mod


Oct 11, 2018
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Olympic Peninsula
C23 & E90 Damper Upgrade

This procedure will cover draining the gel from these dampers and preparing them for mounting with foam filling. If you haven't read the introduction to this post, please check it out here: C23/E90 Gel Filled Damper Solution, it should answer many questions and may be better suited for discussion, comments, or questions regarding this procedure.

Step one is to prepare yourself for the gel itself which needs to be handled with care because it is extremely sticky and messy. The gel is clear and the same consistency as Silicon sealant as it comes from a tube before it dries. However unlike sealant which is rather slimy to the touch, the gel is extremely sticky and never sets. You will want to use exam gloves and have a disposable container to catch it. High strength Alcohol 91% or higher does a pretty good job of cleaning it up. The Gel is a little reluctant to yield to the Alcohol but with a little persistence it will remove it from everything. I have not tried anything less than 91% so I can't guarantee it will work as well.

Removing the Gel.
These dampers have two different ends, one end has obviously been plugged. Hold the damper between your thump and forefinger with the plugged end of the damper up, and squeeze until you see the center of the plug bulge out. The plug has a "T" shape and you will want to cut a circle in the top of the plug's cap to free the inner stopper. This will allow you to pinch and push the plug stopper out along with the gel.

After squeezing as much gel out as you can, submerge the dampers into a small container of Alcohol and pinch them repeatedly while submerged to flush out as much gel as possible. Follow with Q-Tips and Alcohol until you have removed as much gel residue as possible.
This is a short video demonstrating the process: Removing the Gel

The Foam.
Any open cell foam of light density should work fine. I am using leftover segments from a Pelican Pluck & Pick foam insert. These are rectangular pieces with a 5/8"x5/8" (16mm) cross section that I cut into 5/8" (16mm) cubes. I have also seen some 1/2" (13mm) segments, that could be cut 5/8" (16mm) long and would still work well.

For non locking dampers, nothing more is required and you can work the foam inside and mount them to the gimbal as you would any damper. I use a small piece of 1/4" of polystyrene tube, a drinking straw should also work. Roll the foam into a cylinder and work it into the tube or straw until it's all the way inside. Insert the tube all the way into the damper, then using a Hex driver push on the foam thru the tube while slowly pulling the tube out. This will distribute the foam evenly inside and avoid getting it balled up or stuck at one end. Roll the filled damper gently between your fingers to make sure the foam is distributed evenly. Here is a shore video: Inserting the Foam

The following portion is mostly obsolete and needs some editing because of advances in the procedure that are now completely covered in the Inserting the Foam video. No need to read further until I finish editing.




Damper Locks:
The following instructions
Locking dampers are a bit more involved unless you are using @Steve Carr's dental floss method. If so you can skip the following steps because you can thread the floss thru the center of the foam filled damper with a big sewing needle after it has been installed. This is the simplest method of securing the dampers.

If you are planning to use OEM Lock Pins or Zip Ties on any dampers, you will need to cut another hole in the other end of the damper. For this second hole you can either use the Exacto knife or a leather punch for a neater hole. Filling these locking dampers with foam is a little trickier because the order of assembly is different.

When using the OM Lock pins you will first need to make a hole in the center of the foam cube prior to stuffing it in the damper. A leather punch works great for this, or you can flatten the cube on a cutting surface and make a small X in the center with the Exacto knife that penetrates thru. Push the foam cube over a hex driver with a head equal in size to the small end of the OM lock pin and lay this aside. (Hopefully video will soon be posted to replace the poor photos)
ScreenHunter_6079 Dec. 28 19.43.jpg

Mount one end of the damper to a gimbal plate and pass the OM lock pin thru the mounted end. Take the Hex driver with foam cube and place it tip to tip with the lock pin and push the foam cube from the driver onto the lock pin.
ScreenHunter_6075 Dec. 28 19.40.jpg ScreenHunter_6076 Dec. 28 19.40.jpg

Now using a very small Hex driver or similar blunt object work the foam into the damper a little at a time evenly around the pin. What you should have now is a partially installed foam filled damper with the Lock Pin sticking out.
ScreenHunter_6072 Dec. 28 19.35.jpg

Carefully pull the Pin inside just enough to be below the mounting lip of the damper, but still on top of the foam. Take care not pull it down too far or all the way out!

Now you can install the damper into the other gimbal plate as you normally would. Once in place push the lock pin back up and install the lock plate.

Now you have a well mannered robust set of dampers that no longer need to be babied or pampered or constantly cleaned. More importantly you can have a secure retention system that we never had before with the gel filled dampers. And not to mention no more worries about a Hazmat cleanup team response or EPA Impact study if one ever ruptures!
Last edited:
Nov 4, 2018
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C23 & E90 Damper Upgrade
Thank you very much for this idea! I sincerely hope that I can solve the problem in this way.

But only one question: how to remove and install dampers in order not to damage them?

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