SLS valve full rebuild or just let seal?

[blckstrm]

@shogun - might as well get straight to the point, right?

I arrived home from out of town to this;

IMG_20220504_191639.jpg


The failure specifically is that lower 32mm nut - or rather, the seals in that lower assembly.

I've read a lot of shogun's different material as well as this thread on another forum: http://www.bimmerboard.com/forums/posts/779720

My SLS works great - no sagging, grandma owned up until about 15k miles ago, perfect.

It appears to me that only that last outer seal / o-ring has failed. I don't want to disassemble the rest of the mechanism because I don't want to damage the original seals that are still in there and doing their job well.

To be extra clear, there was no leak yesterday (well, hehe, not from that lower SLS valve at least).

My wife sent me that picture this morning. It was empty / no longer dripping when I arrived home. I jacked that side, pulled the wheel, and refilled the reservoir to find the leak. I started the car and it immediately started leaking from the 32mm nut.

All this leads me to believe it's just that last large seal around the 32mm nut. I do not believe the other seals that control the valve are bad. Is that totally wrong, or have others had success with just replacing that last seal when everything else is working fine?

[m60power]

It's likely just the rod seal of the damping valve / module, I had the same thing happen on my 740iL. It failed rather quickly too. See my thread here:

https://www.bimmerforums.com/forum/s...ad+sls+refresh

[blckstrm]

I read your thread a few weeks ago (when I was asking my front suspension question).

I'm sorry I'm being a bit dense - I'm in the middle of an LS3 rebuild on my escalade at the same time and my attention span isn't what it normally is.

You're saying I DO need to remove the nylock nut and springs and replace those seals under the spring, right?

If that's right, 2 follow on questions:

What do you think of the double o- ring solution from that link I posted?

Second - do you still have any of those seals you had made?

[shogun]

Check where it leaks on the shock, top = usually the bombs are dead and cause peak pressure which destroys the top seal. http://www.bimmerboard.com/forums/posts/1261417/
Also check the hydraulic hose from bomb to shock, The lower seal is the easiest, even no need to take the shock out , some links with pics
http://www.bimmerboard.com/forums/posts/779720/ Ken said: Hi It took some searching to find a size that compressed correctly but they were available at my local hardware store out of an assortment case. I would have rather had the dual seal Quad ring style for the small plunger shaft but not to likely to find them at your local store. Attached images from Mc master carr for the O-ring and Quad ring style along with the base o-ring. If I planing ahead these could be ordered ahead of time but since they are Nominal inch series you may find the Standard round profile easy. The 18mm Pocket (708" squeezes the Nom 3/4" (.750") diameter nicely to fit tight and make the 1/2 diameter squeeze to about .448 that fits well on the 12mm shaft http://www.bimmerboard.com/forums/posts/779739
then he changed : Update Installed #206 Viton Quad rings http://www.bimmerboard.com/forums/posts/831490



http://www.bimmerboard.com/forums/posts/1245907/

[m60power]

I read your thread a few weeks ago (when I was asking my front suspension question).

I'm sorry I'm being a bit dense - I'm in the middle of an LS3 rebuild on my escalade at the same time and my attention span isn't what it normally is.

You're saying I DO need to remove the nylock nut and springs and replace those seals under the spring, right?

If that's right, 2 follow on questions:

What do you think of the double o- ring solution from that link I posted?

Second - do you still have any of those seals you had made?

Ah ok, yes I remember that thread now.

No worries, after reading your post again I see what your asking - My assumption is that it's not the outer o-ring seal around the 32mm nut that failed on your strut, but rather the internal valve rod seal. If it is just that outer o-ring, then you don't have to remove the small nyloc nut and springs assembly. In that case it'll be an easy fix. When you refilled the pentosin to verify the leak could you see the fluid leaking from the perimeter of the 32mm nut or was it leaking from the little center dust cap on the bottom of the nut?

You do need to remove the nyloc nut and springs / plates to replace the rod seal under the valve assembly.

I wouldn't put much faith in an o-ring or double o-ring for the valve rod seal. My guess is it would work but not for very long. The ID of the seal is a running surface that the valve rod is constantly moving up and down against, and the 32mm nut housing has very specific features and precise tolerances for the correct seal design.

Yes, I do still have some seals left over, however, I have a list of other forum members who have already asked for my remaining sets, and all my extra seals are claimed. I had held off for a while on selling the extras until I had some miles and time on my struts to verify they would actually work in the long run (they have without issue so far). I somewhat recently sent out the last claimed pair to another forum member already, but I still need to see if the first few folks who asked still want theirs (I still have those sets). I'll PM those members now and if anyone doesn't still want theirs, you're next in line. I'll PM you as soon as I hear back.

[blckstrm]

Ah ok, yes I remember that thread now.

No worries, after reading your post again I see what your asking - My assumption is that it's not the outer o-ring seal around the 32mm nut that failed on your strut, but rather the internal valve rod seal. If it is just that outer o-ring, then you don't have to remove the small nyloc nut and springs assembly. In that case it'll be an easy fix. When you refilled the pentosin to verify the leak could you see the fluid leaking from the perimeter of the 32mm nut or was it leaking from the little center dust cap on the bottom of the nut?

You do need to remove the nyloc nut and springs / plates to replace the rod seal under the valve assembly.

I wouldn't put much faith in an o-ring or double o-ring for the valve rod seal. My guess is it would work but not for very long. The ID of the seal is a running surface that the valve rod is constantly moving up and down against, and the 32mm nut housing has very specific features and precise tolerances for the correct seal design.

Yes, I do still have some seals left over, however, I have a list of other forum members who have already asked for my remaining sets, and all my extra seals are claimed. I had held off for a while on selling the extras until I had some miles and time on my struts to verify they would actually work in the long run (they have without issue so far). I somewhat recently sent out the last claimed pair to another forum member already, but I still need to see if the first few folks who asked still want theirs (I still have those sets). I'll PM those members now and if anyone doesn't still want theirs, you're next in line. I'll PM you as soon as I hear back.

Awesome - thank you!

It seemed it was coming from the perimeter, though I wasn't as detailed in double checking that as I should have been.

I think I'll try just the outer/ 32mm while you verify interest from the other guys.

I forget how much the ENTIRE run cost you, but I'd propose I foot the bill for the next run of 10, and we split the run between us so I get what I need and you get a couple sets to sell as your royalty for the engineering work.

What do you think?

...

Ok, I couldn't NOT look. Got the assembly off and found bits of seal.

I'll use the o-rings in the short- term, but I'm officially interested in bankrolling the next batch!

[m60power]

Awesome - thank you!

It seemed it was coming from the perimeter, though I wasn't as detailed in double checking that as I should have been.

I think I'll try just the outer/ 32mm while you verify interest from the other guys.

I forget how much the ENTIRE run cost you, but I'd propose I foot the bill for the next run of 10, and we split the run between us so I get what I need and you get a couple sets to sell as your royalty for the engineering work.

What do you think?

...

Ok, I couldn't NOT look. Got the assembly off and found bits of seal.

I'll use the o-rings in the short- term, but I'm officially interested in bankrolling the next batch!

Yeah that sounds like a plan, I really appreciate the offer! Honestly, I don't need extra seals at the moment but I'd gladly accept some from you to have as backups, or sell to others that need them. I would only ask for 4 seals (2 sets) if you have a run made and want to send some my way. I have more than one E32, and have been keeping my eye out for more low mileage e32 examples to grab, so it would be good just to have the extra sets if needed in the future! I've been selling my extra seal sets at just my original cost for the seals + shipping, so haven't been looking to make a profit, just recuperate some of my initial cost, and give others a reasonable option to fix their LAD struts.

PM me if you decide to order another production run and need additional info regarding my previous order from Gallagher. I messaged the folks who PM'd me previously about buying the remaining seals I have; I'll let you know after I verify their interest.

[shogun]

if any from the internal valve rod seal production are available, let me know, will take a set or 2. Or a barter trade vs the top SLS seals, still have some sets on stock.

[m60power]

Check where it leaks on the shock, top = usually the bombs are dead and cause peak pressure which destroys the top seal. http://www.bimmerboard.com/forums/posts/1261417/
Also check the hydraulic hose from bomb to shock, The lower seal is the easiest, even no need to take the shock out , some links with pics
http://www.bimmerboard.com/forums/posts/779720/ Ken said: Hi It took some searching to find a size that compressed correctly but they were available at my local hardware store out of an assortment case. I would have rather had the dual seal Quad ring style for the small plunger shaft but not to likely to find them at your local store. Attached images from Mc master carr for the O-ring and Quad ring style along with the base o-ring. If I planing ahead these could be ordered ahead of time but since they are Nominal inch series you may find the Standard round profile easy. The 18mm Pocket (708" squeezes the Nom 3/4" (.750") diameter nicely to fit tight and make the 1/2 diameter squeeze to about .448 that fits well on the 12mm shaft http://www.bimmerboard.com/forums/posts/779739
then he changed : Update Installed #206 Viton Quad rings http://www.bimmerboard.com/forums/posts/831490



http://www.bimmerboard.com/forums/posts/1245907/

Interesting, that Viton quad cross-section ring seems like it could hold up a lot better than a regular circular o-ring. Being Viton it will perform much better in the hydraulic fluid than Buna-N for sure. It seems that his circular Buna-N O-ring failed pretty quickly...

Did he ever provide any updates with how the Quad ring seal performed in the long run?

- - - Updated - - -

if any from the internal valve rod seal production are available, let me know, will take a set or 2. Or a barter trade vs the top SLS seals, still have some sets on stock.

I'll keep you updated; if I don't end up having any more available to send out, blkstrm likely will after a new production run is ordered.

[shogun]

Interesting, that Viton quad cross-section ring seems like it could hold up a lot better than a regular circular o-ring. Being Viton it will perform much better in the hydraulic fluid than Buna-N for sure. It seems that his circular Buna-N O-ring failed pretty quickly...Did he ever provide any updates with how the Quad ring seal performed in the long run?

he never updated it, so it seems that Viton quad cross-section ring works since years