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Bumps after installing Billstein shocks

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Old Jul 28, 2002 | 01:31 PM
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Erik - Denmark's Avatar
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Red face Bumps after installing Billstein shocks

After installing Bilstein rear shock absorbers, I got a ' bumpy' noise from the rear axel when driving low sped over uneven surface.
Is that normal for Billstein shock, or is it a sign of worn suspension links?
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Old Jul 28, 2002 | 03:58 PM
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jpitman1
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Eric,
I think I have heard of something to do with sequence of washers/spacers in the rear being reassembled wrong doing something like this? Maybe check the archives/search.
Interested to see what it is, as I will be doing this sometime soon.
jp
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Old Jul 28, 2002 | 04:02 PM
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I have some sort of noise as well when driving over minor bumps. And now that you mention it I never heard it before I changed the shocks. Mine are bogeys.
regards,
Sab.
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Old Jul 28, 2002 | 05:00 PM
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If you have any kind of gap between the lip of the damper that the spring plate sits against and the spring plate itself, you will hear a loud banging sound every time you go over a small bump as the spring plate hits this lip. You can see this gap when the strut is completely put together and tightened. I had to remove my new rear bilstien's three times to figure this out.

My theory was that the rubber support and the damper bushing were 20 years old and had fallen just a bit so even at max tightness on the top locknut I couldnt get the two peices to seat correctly. It could also be that the Bilstien dampers have a different clearance then the stock dampers.

Eventually I installed a small washer between the spring plate and support plate to tighen the clearance between the spring plate and damper lip to zero and it is now silent as I go over the small bumps.

Or it could be that you broke you stabilizer as you set your car down after the strut install. That has happened to me once. But if your stabilizer isn't damaged then remove your struts and check for that gap.
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Old Jul 28, 2002 | 05:20 PM
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Jake,
Thank you for the advise, I think you got the point - I will check
OK, I installed new rubber damper together with the shocks, but still your theory is a possibility
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Old Jul 29, 2002 | 06:46 AM
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I also installed bilsteins and have bit of a noise also. The handling is fantastic though, wait to hear what you found out before I go any further. Good posts! <img src="graemlins/burnout.gif" border="0" alt="[burnout]" />
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Old Jul 29, 2002 | 12:13 PM
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You know, I took at look at what I posted yesterday and I just realized how hard it is to understand myself. Haha. Since a picture is worth a thousand words maybe this will clear it up.



Part 11 should be seated all the way against the lip halfway up on part 21 when the unit is fully tightened. I had a 1/16" gap between them on both sides and it made a horrible sound. I put a washer between 10 and 11, the gap went to zero and no more noise. Hope this helps better then my screwed up attempt at using the part names.

Jake
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Old Jul 29, 2002 | 01:46 PM
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Jake (and all other)
Wonderful with this free consultancy service
I checked my rear shocks - from the inside of the car! - The problem was exactly what Jake said - The nut (item 5 at page 42-16) at the end of the shock shaft was screwed to the bottom of the thread. I placed two 12 mm Ø distance washers, one over and one under the original conic washer (item 6 page 42-16)
I.e. The shaft end is longer on Billstein shocks, but of course that's my fault, I should have checked this when I mounted them
PS:I do not think I would choose Billstein shocks if I should choose today - They are damn stiff compared to Boge! - But maybe/hopefully they will normalise over the time.
You can see page 42-16 in Jakes post above
Jake I understood, but ok, I was reading your message two times before I saw the light!
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Old Jul 29, 2002 | 01:52 PM
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Yes, but this is for an older model front strut. I've heard the newer models have an adjustable lower spring plate. Mine used to look just like this one before I replaced it.



Jake
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Old Jul 29, 2002 | 01:57 PM
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Erik, that's a great idea! So if I read you correctly, you didn't even have to take the strut out of the car? If so that's a great time saver. I took mine out three times trying to figure out where the damn sound was coming from.

So did the noise go away?

Jake
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Old Jul 29, 2002 | 05:04 PM
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Hi Jake,
No I did not remove the shocks, I installed the distance washers at the top, the result will be the same - The reason I installed one washer under the conic washer was, the hole in the original conic washer (item 6) is only 12 mm and it was 13 mm in the new dishes - This to prevent the original washer to stand on the lip between the thread and the shaft.
The bumps disappeared, now only remains what the very stiff Billstein shocks can say.
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Old Jul 29, 2002 | 08:34 PM
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Erik I just had my seats done which helped because the old seats were so hard. The new seats have much better padding. What do you think of the handling though? Mine is quite incredible although I can't discern between the shocks or the wheels and tires as they were all done at the same time. <img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />
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Old Jul 30, 2002 | 04:19 AM
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Wink

The seats are ok - But the handling of the car is still not 100% ok. Next step will be to change the front shocks and look at the steering house.
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