King Shocks / Coilovers: DIY Rebuild

[Xinirgi]

So this weekend I had the chance to take some pictures of the process involved in rebuilding a set of King Shocks. Almost all brands are very similar (Fox, Icon) to this procedure, so at the minimum if you find nothing else on the internet you could use this.I only went as far as swapping shafts as that's what I needed to do, but with an extra 20 minutes of time you could do everything else while apart. If you have any questions, feel free to ask away!


Work area and prep:
- Start out with clean components, tooling, and work area. This was easy for me since mine were brand new.
- Make sure you have everything BEFORE starting.







1: Loosen wiper cap:
- If you have a reservoir clamp, loosen it and slide it out of the way to get access to the wiper cap.
- Loosen set screw just a few turns. Full removal is not necessary.
- Loosen the wiper cap just a few turns. Do not fully remove it at this point.
NOTE: Leave the shocks charged for this step. The nitrogen charge inside the shock allows for easier loosening of the wiper cap from the seal cap.













2: Check and drain nitrogen charge:
- Check and drain the nitrogen charge.
NOTE: Use a gauge similar to this, it's designed to not drain a lot of air in the checking process. If you use a normal hose style with gauge, you'll end up losing a surprisingly large amount of charge every time you check.










3: Remove wiper cap:
- Loosen the wiper cap the rest of the way and slide it up the shock shaft out the way.







4: Remove retaining ring:
- The ring will most likely be covered by the seal cap. Push the seal cap down until the retaining ring is visible and then remove it.








5: Remove shock shaft, seal cap, and piston assembly:
- Pull the shaft assembly up and out of the cylinder body. Try and go slow, there is a potential for an oil mess if you rush things and get rough.
NOTE: Removing the schrader valve stops the air cavity from creating a vacuum and hindering your progress. If you don't have the tool to remove it, simply bleed the pressure off as you go.

 

[Xinirgi]

6: Place the rod assembly in a vice and start dis-assembly:
- Pay attention to the order things come off, and DO NOT mix anything up. If you do things one at a time there's less chance to make mistakes.
- Parts: Nut, Rebound shims, Piston, Compression shims, Seal cap, Wiper Cap.

























7: Clean / Re-seal / Re-valve / Re-assembly:
- If you're re-sealing or re-valving, this is where you'd clean everything up and remove old / install new seals. Since my shocks were brand new, cleaning and re-sealing were not necessary.
NOTE: Remember to pay attention! I added some pictures to the re-assembly showing things one could miss. I used a little bit of loc-tite (blue) and a paint marker to mark the position of the nut. As an FYI, loc-tite requires a clean and dry surface to work, as well as a cure time.
















8: Setting Internal Floating Piston (IFP) depth in remote / piggyback reservoirs:
- This is a step you don't want to skip. Setting the IFP depth determines how much extra oil you have, and also how effective your nitrogen charge is (based on available volume). This differs from manufacturer's as well as shock design. I emailed King to get the info I have, they provided it with no hassle.


a: With fluid in the shock body and reservoir, bottom out the IFP:
- You can use an air compressor if you're feeling lucky. I used a bicycle hand pump for more control.
- Apply pressure slowly and observe the oil level. If it seems you're getting no movement with moderate pressure, tap the reservoir to bump the IFP.











b: Top off the oil level. This spec is right from King.
- Level should be approximately 1/2” from the snap ring groove on 8”, 10” and 12” stroke shocks, and 1” from the snap ring groove on 14”, 16” and 18” stroke shocks.

 

[Xinirgi]

9: Insert shock shaft assembly:
- Go slow and steady. You will need to bleed air out as you go, rotating the piston as you push down helps release trapped air.
- Pushing the seal cap in takes a bit of force. You want oil to come out as it goes in. If no oil comes out, you either didn't have enough oil, or you had too much air in the system - remove and start again.
NOTE: Removing the schrader valve helps a ton with seating the seal cap. It also allows you to measure the IFP depth to verify it's the same side to side.

























10: Final assembly:
- Apply some air to the shock to seat the seal cap. Only 10-15 PSI is required. Once seated, thread the wiper cap down and tighten it, then tighten the set screw.
- Cycle the shock fully and listen for any air trapped in the system. The shaft should travel with moderate force consistently throughout its stroke. If it is inconsistent you most likely have air in the system and will need to re-start the bleeding process.
- Check the IFP depth, I marked a piece of wire and compared both sides. If one side is considerably different from the other, yeah, you'll need to re-do it.
- Refill the shocks with NITROGEN. Pressures vary by application, manufacturer, and shock. Nitrogen is the only inert gas you should use as it's thermal stability is great. I don't have pictures of this, as my set-up for this isn't at home.

 

[BrianSD_42]

Great stuff.

I am kind of curious, how often do these type of shocks needs to be rebuilt? / What usually causes failure?

Lastly how much would a shop charge to do this work?


Thanks!

 

[shootmymime]

Great stuff.

I am kind of curious, how often do these type of shocks needs to be rebuilt? / What usually causes failure?

Lastly how much would a shop charge to do this work?


Thanks!

these shocks can need to be rebuilt due to leaking seals, bent or pitted shafts, or just changing parts.

some of the more crucial parts that are included in the rebuild kits are
shaft seal, wear bands and dust cap seal.

the rebuild process it quite simple (not requiring large or fancy tools) but it is very easy to mix up the shim stack for rebound or compression shims and cause some drivability problems.

The piston, shim stack for compression and rebound is what off roaders change quite a bit to achieve the most effective off road handling.

(any rebuild able shock is basically the same design, atv, utv, dirt bike, snowmobile.) Ive never done my Kings but i have done my dirt bike.

 

[BrianSD_42]

I'm just curious if these type of shocks get rebuilt every 2 years or 5 years? 50k miles or 100k miles?

It seams like everyone is running full shocks these days.

 

[A.Wilson013]

I'm just curious if these type of shocks get rebuilt every 2 years or 5 years? 50k miles or 100k miles?

It seams like everyone is running full shocks these days.

I rebuilt my icons at about 35k... I think they recommend 30k or so.

I have seen dudes run them for 60k+

 

[absalom]

Great write up ... makes me all the more excited to get my own 2.5's, armed with this knowledge. Op, we need more posts from you.

 

[4-Ripcord]

Definitely saving this thread for later use. Great write-up.

 

[Xinirgi]

Thanks everyone. I didn't necessarily rebuild mine, what happened was these were a custom order shock and they were sent with the wrong shafts originally. King offered to rebuild them for me if I sent them back, which I declined as I am in Canada and didn't want to wait even longer before installing them. Instead they sent the replacement shafts and a gallon of oil free of charge and I did them myself.

King and other companies have a general guideline regarding the time in between rebuilding or simply changing the oil. I have misplaced the paperwork with that information, I'll have another look around and post it up if I find it.

No clue what a shop would charge, I don't have anyone local that can do it, hence why I simply did it myself. Other than the charging of nitrogen, you can do it all with basic hand tools. I have a nitrogen setup at work I used to finish these up.

 

[BrianSD_42]

Putting this in the next update of:

http://www.toyota-4runner.org/3rd-g...faq-tutorials-documentation-reference-v2.html

 

[Bijan]

motherf*cker!

man even with this superbly written write up I dont think this task is something I would want to tackle OR try to find anyone to trust to do it.

Good work dude, keep up the awesome write ups!

 

[jacobbert9]

Lastly how much would a shop charge to do this work?

Thanks!

A little late, but just in case anyone else is checking out this thread.. I found a local shop in the Dallas/Fort Worth area that rebuilds shocks. Said it would take half an hour per shock at $95/hr. I'm going to rebuild my own and just have them charge with nitrogen for $20.