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632 Regal
03-12-2005, 05:31 PM
on the strut mount under the hood, the 22mm nut, should I be able to turn it fairly easy? Not that the nuts loose or anything I mean the shaft that goes through the rubber mounts and all, mine can spin while I hear rubber squeeking...hard to explain. Trying to locate front clunk noise. The nut is tight as can be.

Jose
03-12-2005, 05:34 PM
What kind of klunk, when steering or driving over small short bumps ?

Qsilver7
03-12-2005, 07:20 PM
...it may be a failed guide support. Sometimes the rubber rips/tears and even though the nut is screwed on...when going over bumps...the shaft pushes upward through the guide (which is now ripped) and makes the clunking sound.

When you open the hood...push down on the side that you hear the clunk and see if the rod is moving upward. (see #1/#5/#6 in diagram...I don't think you have #13)

Click here for diagram of front suspension: http://www.realoem.com/bmw/showparts.do?model=HE23&mospid=47406&prod=19940400&btnr=31_0123&hg=31&fg=10

632 Regal
03-12-2005, 07:44 PM
Yes on small bumps and it isnt the sway bar links or anything else obvious under there.

the rod kinda moves up and down if I rock the car, not a lot but its obvious that its not real tight to the rubber on top, it does about the same amount of movement on both sides but only clunks on the drivers side.
What im thinking is from my stupid mile of frozen mud road something went awry. Im getting thrust arm shimmy after a year which isnt normal but probably from that damn road, constantly slams and bottoms the shocks.
Am I correct in thinking that there is no upward rubber insulation on the strut shaft to the guide plate and only rubber on the top? There isnt any way of duplicating the clunk unless its on mudville road or other big type bumps.
If the guide goes bad, can this cause a clunk?

632 Regal
03-12-2005, 08:02 PM
I wish I could find a diagram or something of whats all in these things and how they are put together.

Qsilver7
03-12-2005, 08:03 PM
the rod is not supposed to move upward into the engine bay...if you see any movement at all...they have failed. The reason it may be only clunking on one side is that it has more deterioration...meaning the rip/tear is probably more invasive.

I've never had front support guides fail...but I have had the rear ones fail onmy old e30 & e32. The clunking sound was annoying and took awhile to figure what was causing it (on the e30). When it happened to my e32...I sort of knew what to check...and sure enough...the rubber had ripped/torn and I could see the rear strut's rod move upward taking the nut at the top with it. This upward/downward movement would make the clunk sound when driving on uneven surfaces.

632 Regal
03-12-2005, 08:28 PM
what rubber are you talking about tearing? I just cant picture the thing in my mind. I'll probably get a used one or two since they last forever but still dont understand whats broke...lol Im anal about everything.

Qsilver7
03-12-2005, 09:15 PM
what rubber are you talking about tearing? I just cant picture the thing in my mind. I'll probably get a used one or two since they last forever but still dont understand whats broke...lol Im anal about everything.
If you did, item #1 is rubber...or at least they were rubber on my e30 and e32.

Here's a pic of a rear guide support (also called strut mount) that has failed. You can see how the rod (from the shock/strut) moves upward...the clunking sound comes from this failure to contain the rod and it moves up and down over bumps: http://hock.net/images/bmw/rear-strut-mounts/strut-mount-revealed.jpg

Here's another pic of the guide support (strut mount). The old one is on the left and the new one is on the right. They are made of rubber and fit directly underneath the metal strut tower under the hood (with the screws sticking up through the metal). The rubber generally rips or tears at the base of the rubber section in the middle that you see that is raised:http://hock.net/images/bmw/rear-strut-mounts/strut-mounts-old-and-new.jpg

Sorry I couldn't find a pic of the front strut mount...I just went out on Google and did a quick search and found this pic of a failed rear one.

632 Regal
03-12-2005, 09:50 PM
i did look at the realoem site even before posting this. My supports or "guides" dont look like anything pushed its way through itself, I see what your talking about now on the ripped rubber deal. I dont think the fronts are made like that. My idea is NOW that everytime my strut bottoms and slams, its actually "slamming" against the guide and not a rubber insulator and must have somehow caused play in the bearing where its pressed together? I mean thats all I can imagine at this point without seeing mine all taken apart so far. The upward pressure in the strut is a constant upward pressure so its impossible to duplicate whats happening at speed. I also did a search on google with the part number but didnt come up with a cross section.

Qsilver7
03-12-2005, 10:03 PM
here's a pic of the front strut mount (support guide)...you can see the rubber beneath the strut tower and how the rod comes up thru the center:http://www.pelicanparts.com/bmw/techarticles/E30-Front_Suspen/pic23.jpg

You can see the beginning of a stress tear starting just above the black center cap in this pic below. If the rubber rips/fails, the strut's rod will move upward and the metal stopper & nut (#5 & #6 in the diagram in my 1st post) will clunk as it moves up & down:http://www.pelicanparts.com/bmw/techarticles/E30-Front_Suspen/pic24.jpg

632 Regal
03-12-2005, 10:24 PM
sweet man! OK, so if I remove the nut and upper rubber bushing deal I should be able to see the lower rubber deal failing correct?

The nut is real tight and started bending my allen wrench trying to loosen this thing so Im not sure how Im going to loosen it up without ruining my new shocks. Im thinking my impact will just spin the shaft without gripping it with vice grips from the bottom. I dont remember seeing that rubber lower deal but it might just be there! LOL I really appreciate this from you and my mind is pretty much like an elephant (unless im havin a few beers) so hopefully I wont need to go back to this, I'll just know...I hope...:D

winfred
03-12-2005, 11:10 PM
theres a few different styles of upper mounts, i zap those nuts with a impact all of the time, if the piston spins i pulse the impact and it grabs after a few hits

632 Regal
03-12-2005, 11:42 PM
Winfred, remove it and inspect it, what shall I find if it's bad?

winfred
03-13-2005, 12:03 AM
i am not sure that you would find anything unless it was put together wrong, usual sorces for clunk/knock type noises, loose strut insert hold down collar, worn balljoint (just did a 525 with a nasty clunk that had totally wornout control arm and thrust arm joints on the drivers side) thrust arm bushing (you usually get a clunk if you tap the brake hard) sway bar link, really worn out strut insert, crappy ill fitting brake pads/missing spring clip and last but not least crappy ill fitting strut/wrong combo of strut and upper mount or put together in wrong order (spacers and or washers in wrong place)