My general tips for shock rebuild

Hello,

The last days I am into rebuilding my king shocks and now after having three done and still three remaining I am getting much faster with it. With this post I want to share my general tips which I figured out over the process and with internet research on thinks which weren't covered by the general available manuals.

Additional useful tools:
- rubber strap wrench to hold the shock body for removing the head caps. Don't use/needed the aluminum vise clamps so far
- manualy driven tire/bicycle air pump to slowly pressurize the reservoirs for disassambly
- oil drip pan for motor oil change to collect the oil
- syringe to remove or fill in small quantities of oil

Tips:
- during disassembly start first with the main shock before the reservoir. After you pushed down the main head cap to get access to the snap ring it is hard to get this head cap back up and removed from the shock. Now with slowly pressurizeing of the reservoir with the air pump you force the oil out of the reservoir into the shock which pushes then the cap out. During this process you almost need no force and you can control it slowly enough to not spill too much oil.

- same procedure can be used for the reservoir disassembly

- during oil fill up the Piston of the reservoir can be almost all the way at the hose side (maybe leave a 5mm gap). While installing the shock head cap you will eventually force enough oil into the resorvoir

- before pushing in the head cap you want to remove the reservoir cap with the shrader valve so that no pressure builds up in the reservoir which will make it harder pushing in the head cap

- when pushing in the head cap you want to make sure that a little bit of oil overflows, otherwise you can't be sure that air is trapped inside.

- when pushing in the head cap you want to make sure that the Piston is as far extended as possible otherwise you might not have enough oil in the shock. The oil will be suppressed by the rod when it is fully immersed in the oil.

- removing the springs from a coilover is not a big deal when you have the right tool. I was lucky to find a coworker who owns a Branick which he let me use. With short introduction by him I was able to remove one spring in roughly 5 min. A day before a local car repair shop wanted to charger me 50$ just to remove two spring which I was later able to do in just a few minutes.

- the whole rebuild can be roughly done in an hour when you get the hang of it and you don't clean everything excessively

- for 6 shocks I bought 6 rebuild kits and 2 gallon of oil which cost me 220$
Sending these in for rebuild I would probably end up at 800$ included additional labor and shipping

- I was not able to find a store in my region which is able to refill the reservoir with nitrogen so I decided to build a kit myself before spending all the money on shipping the shocks.
So when anyone in South East Michigan/ close to Detroit needs a refill don't hesitate to shoot me a PM.

Please be aware... I don't take any responsibility in case something goes wrong while following these tips

 

A picture for the location of the piston (see small hole). Did not memorize it and had to open another shock first.


Bypass shock: The white plastic piece without a hole in the middle goes to the rebound side


Before
and after treatment with scotch bride and mothers metall polish

 

What does your nitro charging set up look like?

 

Here is a pic ..

 

Oooooo that’s slick, get the regulators on Amazon?

 

Thanks for the tips, Im starting to get my head wrapped around what exactly Ill need to do mine. Do you happen to have any of the pdf manuals you mentioned?

 

It’s quite some time ago but I think I was referring to the pdf you can find here
https://www.filthymotorsports.com/Articles.asp?ID=265

 

Follow instructions from filthy motorsports. They also have a very detailed video on youtube. Just take your time and photograph things as you go so you know how it goes back together. Really simple process after doing it a few times. Hard to screw up

 

Cool good to know. I typically make it more complicated in my head than it has to be until I dive in haha

Are either of you guys in cold weather climates? I have heard that Fox oil behaves better in colder temps which may be of interest to me up here in Maine. Im considering doing the rebuild with that oil instead of King's.

 

I just moved from Florida up to Delaware a few months ago. This will be my first winter up here. We shall see how all my fluids do

 

King uses Shell Tellus T22 mineral hydraulic fluid, last I knew anyway. Pour point is around -40F. The Fox JM92 fluid, which might be Torco RSF, is synthetic and has a -70F pour point. So yes, it will perform far better in our below zero New England winters. The Shell is a 22 weight oil, and the Fox is maybe a 15W?... need to brush up. Not a bad idea to jump down the suspension fluid/oil rabbit hole for even a short time, plenty to learn about.

 

I live in Michigan but my truck is really just used for camping and traveling. In the winter time it gets a break especially with the salt I don’t want to have the frame rust out.
So I can’t say much about how the shocks behave in the cold unfortunately.

 

how confident are you that king is really using the shell oil you mentioned?
I am just asking, because this could Safe quite a few bucks by buying it directly without the branding

 

The info comes from desert crowd, plenty of info on it over the years... Let me double check the weights.

 

I dont have time for another rabbit hole

 

Shock oil volume?

I am rebuilding my 3-year-old 2.5 6" stroke coilover shock without a reservoir and don't know how much oil is needed.

When dumping the old oil, both shocks measured at 300cc.

I found a rebuild instruction sheet @ filthymotosports that reads:
For emulsion (non-reservoir) shocks use these volumes instead:
2.5 x 6” 400 cc
2.5 x 8” 510 cc
2.5 x 10” 640 cc
2.5 x 12” 800 cc
2.5 x 14” 900 cc
2.5 x 16” 1,000 cc

I'm conflicted - does anyone have experience or know how much oil is required?
Not many resources on oil volume.

 

I've never really measured. I just fill it to just below the snap ring