front top mount and coilover "boinging"

[p 5ary]

Any advice appreciated with this one,

basically im trying to sort out a "boing" sound that keeps coming from my front coilovers, when i turn the steering wheel i expect the coilovers to turn with it, yes?

but... im finding that the coilover is reluctant to turn and the result is the spring sliding across the coilover at the bottom to try and counter the rotation , here>>>

http://i31.photobucket.com/albums/c393/p5ary/BMW/how%20to%20lower%20april%2006/DSCF0020.jpg.

ive tried loosening the top nut of the coilover as at first i thought it was a bit tight but nope not it, the required torque setting of the top nut is 32nm so tight enough.

the top nut its free when the nut is barely touching the washer , as soon as it touches the washer it is biting in and not as free, any torque on the nut and "boing boing", the tighter the nut the worse it is.
when i had the nut totally loosened it allowed the strut to turn, i can get at the nut from the engine luckily as I'm really trying to avoid needing to remove the entire strut although i realise this is like trying to make an omelette without breaking eggs:$ .

everthing on this diagram on the left hand side up to but not including nr 8 in the middle has been installed as oem

http://i31.photobucket.com/albums/c393/p5ary/GENERAL/topmount.jpg

and heres the part nrs

http://i31.photobucket.com/albums/c393/p5ary/GENERAL/partnrs.jpg

any help to reduce the "boinging" greatly appreciated

[p 5ary]

the main part i have a query with is the washer kw give you that was attached with the front strut when new, im thinking this may be in the wrong position , i have it placed just below the nut they give you above the top mount. im a bit worried this should be at the btm of the top mount but above the dished washer from the oem suspension.

[exdos]

p 5ary,

I presume that the "boinging" noise is due to the larger spring being held captive at both ends, so that when the steering is turned, the spring is partially uncoiled/coiled rather than remaining just compressed inbetween the two purple spring perches, and the noise is as a result of the springs returning to their coiled state.

I am wondering if you are getting this boinging noise when you turn the steering when the wheels are off the hubs. What I'm wondering is: are the inner walls of the front tyres catching against the springs and forcing the springs to rotate? Are you 100% sure that your wheel spacer are giving you sufficient clearance during turning of the steering? Alternatively, are the grub screws in the spring perches shown in the photo fastened properly; from memory these should be torqued to 2Nm?

Another suggestion is: have you got the spring perch which fits between the large spring and the smaller "helper" spring correctly positioned (if there is a right way up)?

From the top of my head I can't remember the order of what goes where in assembling the KW dampers on to the front top mounts but when I fitted my KW suspension it seemed to be pretty much self-evident as to how to do the job properly.

Good luck!

[M3 Compact]

Doesn't sound right. :cry:

Possibly relevant? (http://forum.bmwcarmagazine.com/topic.asp?TOPIC_ID=33809)

[p 5ary]

Exdos and m3 compact, thank you for the reply, im sure the forum is sick of reading about my kw disasters :lol: :lol:

p 5ary,

I presume that the "boinging" noise is due to the larger spring being held captive at both ends, so that when the steering is turned, the spring is partially uncoiled/coiled rather than remaining just compressed inbetween the two purple spring perches, and the noise is as a result of the springs returning to their coiled state.


Thats what i was trying to describe :oops: although i think it may be captive at one end only as the bottom perch with the grub will turn with the hub as it has no choice but to turn



I am wondering if you are getting this boinging noise when you turn the steering when the wheels are off the hubs. What I'm wondering is: are the inner walls of the front tyres catching against the springs and forcing the springs to rotate? Are you 100% sure that your wheel spacer are giving you sufficient clearance during turning of the steering? Alternatively, are the grub screws in the spring perches shown in the photo fastened properly; from memory these should be torqued to 2Nm?



im definately achieving the minimal gap although will try it with the wheel of the hub and turn for piece of mind, tyre spins freely when off the ground and can fit a good 3mm object between coilover and tyre when off the ground,
PS i really hope its not the tyres as i just got 2 new front tyres today (boinging was happening before new tyres went on).

checked the grub screws and tightened them (2nm is spot on)



Another suggestion is: have you got the spring perch which fits between the large spring and the smaller "helper" spring correctly positioned (if there is a right way up)?


From the top of my head I can't remember the order of what goes where in assembling the KW dampers on to the front top mounts but when I fitted my KW suspension it seemed to be pretty much self-evident as to how to do the job properly.

Good luck!

heres the way its gone in, basically top mount just sat on top??? then added new kw washer and kw nut?? ( the instructions are sooo bad its unbelieveable, ive tried their site to try and find any further instructions but no joy

http://i31.photobucket.com/albums/c393/p5ary/BMW/how%20to%20lower%20april%2006/DSCF006.jpg

http://i31.photobucket.com/albums/c393/p5ary/BMW/how%20to%20lower%20april%2006/DSF0007.jpg

[exdos]

p 5ary,

The photos of your front coilover looks right. the only bit that is missing is the front tower reinforcement ring (Part 15 in the realoem parts diagram).

The large washer fitted below the top mount looks a bit rusty, if you were to clean this up and smear it with a little grease might this help, because any friction that the corrosion might cause will be considerably increased when the damper is loaded ?

Is this boinging noise coming from both sides or just one side only? If you're dismantling the front suspenion to sort this problem out, how about swapping the springs over L >R and R >L, and also inverting them to see if that makes any difference.

Have you fitted uprated ARBs? Most of us who've recently changed to H&R are finding that this finds out any weakness in the stabiliser links. The symptoms are noise on turning, especially at very low speed. I know Steve1 had a problem of a noise which he couldn't cure which was driving him nuts. Like you he'd recently fitted Rogue top mounts and thought that the noise was from those so he swapped back to OEM rear top mounts. (I know you recently sold your Rogue mounts). However, it transpired to be the front stabiliser links. He's now made some stronger ones which have cured the problem.

I'm finding that with a much stiffer ARB and KW V3 that under heavy braking, I get a slight juddering, which feels like wheels out of balance, but I think it is because the front stabiliser link is under compression due to pitching and the stabiliser links are acting like Rolf Harris' wobble-board. I've submitted a request for help from KW with this, but I doubt if they'll be much use, since they will no doubt claim the problem is due to the H&R product.


These drop links from demon tweeks my be the answer: http://www.demon-tweeks.co.uk/products/ProductDetail.asp?cls=ROAD&pcode=WHIKLC40-060
From memory, the stabiliser links which KW supply have the 2 bolts at 180mm centres, whilst you've got the suspension dismantled, can you give me the exact measurement please.

Hope this helps.

I did warn everyone that KW is the WORST company I've ever dealt with :cry: :cry:

[p 5ary]

ive managed to sort the boinging for now, basically the the top nut is compressing the top mount bearing too much, making the top purple perch stick against the rusty washer.
(a difficult job to do by yourself until i found that i could turn the wheels by literally turning the wheels, with the car jacked both sides and started up, made identifying the boing much easier).

basically i think the top purple perch should rotate freely whilst the washer should be static although this seems difficult to achieved as surely a bearing of some sort should be between the perch and washer??.

i was going to remove both struts and change over the top mounts but thankfully have cured it for now (photos where taken during initial installation, theyre still fitted at the moment)
ohh and tower reinforcement was installed just didnt have it on at that photo lol.

Exdos, thanks for taking the time to help, if your ever over in belfast ill have to buy you a large number of drinks!

[exdos]

Exdos, thanks for taking the time to help, if your ever over in belfast ill have to buy you a large number of drinks!

Glad you've got it sorted :D 8)

You can always come over to England and buy me the drinks here :wink: :lol: