Bilstein B6 problem

[igor136]

Hi to all.
I had a problem with my Audi UrS6.
"KLANK" was sometimes heard on the left front wheel.
I have a Bilstein B6 on all wheels.
I suspected the shock absorber.
After I loosened the shock absorber triangle bearing bolts, BOOM.
The shock absorber flew out of the case. It split into 2 parts.
I was lucky. Did I make a mistake because I didn’t drill a hole in the bottom of the case? That water or oil can come out. Anyway, the shock absorber should not have exploded.
Does anyone have similar experiences?
Tnx Igor.

[igor136]

rsz_120211103_184235.jpg

[Lago Blue]

Igor,

I have not had that happen but suspect (from your photo), that your piston rod and bump-stop may still be inside the yellow tube (the rod still screwed into the base of the yellow tube?). If yes, then the nut which fastens the piston (last photo) to the rod has come undone (and could perhaps be heard to rattle inside the silver body). If yes, then this may be a factory assembly problem that you could approach Bilstein about.

Screen Shot 2021-11-03 at 22.34.34.png Screen Shot 2021-11-03 at 22.30.19.png Screen Shot 2021-11-03 at 22.26.17.png

[s2driveruk]

Sounds nasty, how much force did that leave the strut with? I would absolutely be approaching Bilstein about it too.

[igor136]

Thank you for your answers.
Everything is still in the yellow tube (shock absorber housing).
The shock absorber piston is empty. So there is nothing inside it. Empty tube.
That was nasty. I didn't even see what happened. I just heard a shot. Confused I look and don’t see the shock absorber in place. He was in the garage, between tools. It was like a rocket.
I also damaged the hood. But I don't care.

[K Simmonds]

Oh my word, just read this post as I had been working on my C4 100's front suspension... If that had clouted you if the face with the force you describe it could have killed you. Kinda puts me off B6's!

[s2driveruk]

I have some in mine which i realised have been there since 2003. Was thinking about replacing them and probably will but this adds a dimension of risk that makes me very uncomfortable to do it on a bench!!!

[K Simmonds]

Your dam right! I have some on the front of my RS2, which I fitted back in 2016, I also forgot to drill holes in the bottom of the struts... I'm going to have to carefully take them apart again and tackle this job once I can use my arms properly again. However I'm going to make very sure I'm not in the line of fire so to speak at any point. To be fair this is the only case of this happening I've ever heard of, but once is all it take's sometimes to have truly deadly consequence's.

[igor136]

It was brutal energy.
New shock absorbers were installed yesterday.
No more shock absorber sound.
To be honest, I didn’t drill holes in the case. I am afraid that water will enter through that hole, which will cause a water hammer.
The right shock absorber was fine. While still in the car, a little unscrewed, you can feel if he is too tense or not. In fact, you need to be able to press it with your hand. Hard but it goes.
Honestly, I think the original shock absorbers are better for our cars.

[K Simmonds]

You had a very lucky escape IMO, I'm pretty sure the energy required to send that much mass flying across a workshop would either seriously maim or more likely kill you.

Using spring compressors always makes me a touch edgy but this is a whole new level of scary!

What replacements did you go for? I've got some random German made replacement's for my C4 100, can't recall the brand off hand as they came with the car, if I'd purchased them myself I'd be able to remember.

[Lago Blue]

Perhaps as a general rule, we should all be more considerate of the possible risks involved that we may encounter everyday somewhat casually (assumed familiarity breeds contempt) in auto maintenance, simply because we have not seen a particular fault before. IIRC, even the factory original dampers were gas pressurized. As Mr. Simmonds rightly suggests above, to always keep the weapon pointed down range would be a prudent precaution.

I share Mr. Simmonds apprehension when compressing main springs, similarly removing the brake accumulator, seating a tire bead on a 30-year old alloy wheel and even just jacking up the car always gives me pause to think about working safe. There are spring compressors more confidence inspiring than others (1st photo) well worth the money but of little help here. This issue (as I'm not familiar with the larger car's top-mount arrangements) on a B2, 3 or 4 would (with a still intact top-mount!) also present when one goes to remove the strut from the fender-well, but perhaps differently.

If the damper halves became unattached while installed, when the car is raised, I believe the strut would continue to extend until the internal pressure was allowed to escape or the suspension travel was blocked by the axle, if present. If correct, and it did not come apart as the car was raised, then the first visual sign of the problem might be that the main spring (perhaps if of stock or near to stock length only?) would become loose between its perches. The second clue might be the difficulty in removing the second strut to hub carrier bolt. At this point is where one should stop. I'll have to have a think on what I'd do next (call Bilstein?). Another drain hole somewhere to allow the still trapped pressure to be bled off safely in such an event comes to mind, but exactly where?

Igor,

Perhaps this will allay your concerns re the drain / vent hole mod to the strut base. I don't yet see a possible connection between this mod's either presence or absence and your issue, but I could be wrong. Nevertheless, gravity is our friend here and said mod simply allows any water that would otherwise accumulate, to have a route to fall out. Because of the height of the strut base above the axle (2nd photo) one would have to be in deep and parked to have water get in; and stay there.

Strut-Master w front strut Screen Shot 2021-11-11 at 06.10.51.png UrQ Fr strut base height above wheel centreline Screen Shot 2021-11-11 at 04.55.40.png

[NickzD]

It was brutal energy.
New shock absorbers were installed yesterday.
No more shock absorber sound.
To be honest, I didn’t drill holes in the case. I am afraid that water will enter through that hole, which will cause a water hammer.
The right shock absorber was fine. While still in the car, a little unscrewed, you can feel if he is too tense or not. In fact, you need to be able to press it with your hand. Hard but it goes.
Honestly, I think the original shock absorbers are better for our cars.

My friend is looking at an S2 with some suspension noise.The stock shocks probably need replacement. We'll take a closer look soon after we install the wheels and suspension from 4Wheelonline onto the truck project.

[Cordoba16vt]

Hi to all.
I had a problem with my Audi UrS6.
"KLANK" was sometimes heard on the left front wheel.
I have a Bilstein B6 on all wheels.
I suspected the shock absorber.
After I loosened the shock absorber triangle bearing bolts, BOOM.
The shock absorber flew out of the case. It split into 2 parts.
I was lucky. Did I make a mistake because I didn’t drill a hole in the bottom of the case? That water or oil can come out. Anyway, the shock absorber should not have exploded.
Does anyone have similar experiences?
Tnx Igor.

What suspension springs are on the car in combination with the B6 shocks?

[igor136]

The originals that were on the car. I can still hear that KLANK. Is the problem perhaps incompatible parts?

[igor136]

Perhaps as a general rule, we should all be more considerate of the possible risks involved that we may encounter everyday somewhat casually (assumed familiarity breeds contempt) in auto maintenance, simply because we have not seen a particular fault before. IIRC, even the factory original dampers were gas pressurized. As Mr. Simmonds rightly suggests above, to always keep the weapon pointed down range would be a prudent precaution.

I share Mr. Simmonds apprehension when compressing main springs, similarly removing the brake accumulator, seating a tire bead on a 30-year old alloy wheel and even just jacking up the car always gives me pause to think about working safe. There are spring compressors more confidence inspiring than others (1st photo) well worth the money but of little help here. This issue (as I'm not familiar with the larger car's top-mount arrangements) on a B2, 3 or 4 would (with a still intact top-mount!) also present when one goes to remove the strut from the fender-well, but perhaps differently.

If the damper halves became unattached while installed, when the car is raised, I believe the strut would continue to extend until the internal pressure was allowed to escape or the suspension travel was blocked by the axle, if present. If correct, and it did not come apart as the car was raised, then the first visual sign of the problem might be that the main spring (perhaps if of stock or near to stock length only?) would become loose between its perches. The second clue might be the difficulty in removing the second strut to hub carrier bolt. At this point is where one should stop. I'll have to have a think on what I'd do next (call Bilstein?). Another drain hole somewhere to allow the still trapped pressure to be bled off safely in such an event comes to mind, but exactly where?

Igor,

Perhaps this will allay your concerns re the drain / vent hole mod to the strut base. I don't yet see a possible connection between this mod's either presence or absence and your issue, but I could be wrong. Nevertheless, gravity is our friend here and said mod simply allows any water that would otherwise accumulate, to have a route to fall out. Because of the height of the strut base above the axle (2nd photo) one would have to be in deep and parked to have water get in; and stay there.

Strut-Master w front strut Screen Shot 2021-11-11 at 06.10.51.png UrQ Fr strut base height above wheel centreline Screen Shot 2021-11-11 at 04.55.40.png

Sorry I just read your post. Everything you said is true. We take some things lightly. Thank you very much.