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Shock seal head keeps bouncing back (2004 YZ250F)

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Hey guys! Hope y'all are good.

I'm trying to disassemble the rear shock of my 04 YZ250f. Spring is out, dust cap is out, bladder has been emptied and valve stem removed. 

I see in all of the youtube videos that you should just press the seal head in, as well as the bladder cap to be able to remove the circlips. I've been trying to do it for hours but they just keep bouncing up! As soon as I remove the pressure they come back seating against the circlip. 

Is there anything I'm missing? The shop manual doesn't talk about overhauling the shock, I'm at a complete loss :(

Thank you for your help! happy Friday

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Can't you just hold it down and use your pick?

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Easier said than done... haha.

I'm pushing down on the bladder head with the hammer handle while trying to fish it out... after about half an hour my technique is getting better.

It feels like there is pressurized air inside of the shock... but it can't be! Even the valve stem is out.

Will update shortly...

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If all of the oil is out too, then the seal head should stay down enough. Did you remove the comp adjuster? That will help drain the oil.

Edited by DEMI

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@DEMI you mean this one? How do you go around it? Do you remove the whole thing? Or just the brass nut?

Thanks!!

20200626_120657.jpg

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Try this, compress the shock, let the air out with the Schrader valve in, then extend the shock and you should be able to push in the seal head or bladder cap and they should stay in, then remove clips 

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Be careful it's full of air and is causing a huge pressure 

 

You have to carefully unscrew the adjuster with the flats, not the nut 

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@mog thanks man! I tried it before posting and for some reason the whole body with the two flats just spins and doesn't come off. I went home and started investigating how to take that off. Will keep you guys informed.

Thanks again!

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It's threaded, it should not just spin, it's a fine thread 

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May have to pull on it a bit because of the o-ring...should just come out. 

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You don't want to pull the seal head and clevis until there is no pressure in the shock.  Don't bother until the seal head can be pushed in and stays in.

When enough gas seeps through the bladder into the oil you won't be able to relieve the pressure by deflating the bladder.  Some shocks have a bleed screw in the shock body you can use, others require removal of the comp adjuster.  Like mog said, be careful and go slow.  If you unthread the adjuster completely and there is still pressure behind it you're going to have quite a mess.

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@turbo dan I had that in mind today, had the shock covered with a supermarket bag while I was wrenching it on the inside haha.

Thank you for your advice, let me try again and let y'all know how it goes.

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I recently had a shock in my shop with the same symptoms, we ended up making a jig to hold the seal head down in an arbor press just long enough to get the snap ring out. the oil IS under pressure, air has entered the shock body and you will have a foamy mess when you finally get the seal head free. Wear eye protection and plan for a foamy oil mess. You can also remove the compression adjuster, but I would do that very carefully as it will also be under the same pressure. 

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Definitely remove the comp adjuster before you remove the seal head!

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@chelder yeah that's actually the first thing I'm going to do when I get to the shop in the morning. I even got a sacrificial rag to contain the oil jet that's going to come out of there haha

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1 minute ago, The_Primo said:

@chelder yeah that's actually the first thing I'm going to do when I get to the shop in the morning. I even got a sacrificial rag to contain the oil jet that's going to come out of there haha

Yeah its not to bad just go slow and face it away from you into a tub put the rag over it and unscrew slowly.

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@redhurricane yeah I didn't know that the nitrogen can migrate to the oil compartment and the damn thing is pretty high pressure as it takes a lot of effort to push the bladder head and the seal head down. Will wrap the thing in a thick rag when I pull out the comp adjuster in the morning.

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