Rear suspension knock

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dmad_dood
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Rear suspension knock

Postby dmad_dood » Mon Nov 25, 2013 6:19 pm

First off i've done a search and didn't find much in the likes of helping my issue so hear i am,

I changed the suspension on my car and then did a wheel alignment a while back but i'm getting a knock from the rear left. Ive tried just about everything i can think of to remedy the situation like moving the exhaust, reinstalling the coilovers, checking over the bolts 30 times, checking clearances etc..

its been like this for a few months now and happened as soon as i changed my coilovers over.

The noise only happens when driving over small bumps and bigger, the noise gets worse in successive bumps. It also makes the car jump slightly. Could i maybe be an issue with the coilover itself?

Im all out of ideas, can anyone help?

Cheers,

Jono.
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Regie
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Re: Rear suspension knock

Postby Regie » Mon Nov 25, 2013 6:58 pm

disconnect one of the sway bar end links and take it for a drive.

if the knock disappears, the bearings in the end links are stuffed.

This happened to my NB a few years ago
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dmad_dood
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Re: Rear suspension knock

Postby dmad_dood » Mon Nov 25, 2013 8:27 pm

Regie wrote:disconnect one of the sway bar end links and take it for a drive.

if the knock disappears, the bearings in the end links are stuffed.

This happened to my NB a few years ago


Ill give that a go, its worth a try. Thanks

Jono.
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hks_kansei
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Re: Rear suspension knock

Postby hks_kansei » Tue Nov 26, 2013 12:53 pm

What sort of wheels are on it?

They tyres may be lightly clipping the guards if they're wide/low offset.
Perhaps after the alignment/coilovers (height change?) they now clip (less negative camber maybe?)


Also check easy stuff like making sure the spare tyre and battery are clamped down firmly.
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dmad_dood
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Re: Rear suspension knock

Postby dmad_dood » Tue Nov 26, 2013 6:12 pm

hks_kansei wrote:What sort of wheels are on it?

They tyres may be lightly clipping the guards if they're wide/low offset.
Perhaps after the alignment/coilovers (height change?) they now clip (less negative camber maybe?)


Also check easy stuff like making sure the spare tyre and battery are clamped down firmly.


Ive got plenty of clearance in the guards and my wheels are very close to stock offset so i can rule that out, ive also checked the spare tyre, battery and jack to make sure there not moving around.
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Re: Rear suspension knock

Postby Sailor » Tue Nov 26, 2013 7:26 pm

Check that the nut on the top of the shock shaft is tight.
Rob


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dmad_dood
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Re: Rear suspension knock

Postby dmad_dood » Tue Nov 26, 2013 7:47 pm

I remember trying to tighten that a while back but I think everything just span if I remember correctly and I wasn't sure how tight it should of been either


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PT
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Re: Rear suspension knock

Postby PT » Tue Nov 26, 2013 8:02 pm

I had the same thing when I installed coil overs and then had a wheel alignment done. The eccentric bolts need to be very very tight. If they are not tight enough you will get a knock that sounds like there is something loose in the boot. Like metal on metal sound.
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dmad_dood
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Re: Rear suspension knock

Postby dmad_dood » Tue Nov 26, 2013 8:23 pm

Thats the sound. Like a sort of dull thud metal on metal sound?

Now which are the eccentric bolts? The bolts that to through the bottom of the coilover?
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aka_juffa
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Re: Rear suspension knock

Postby aka_juffa » Tue Nov 26, 2013 9:28 pm

dmad_dood wrote:Thats the sound. Like a sort of dull thud metal on metal sound?

Now which are the eccentric bolts? The bolts that to through the bottom of the coilover?

There are 4 eccentric bolts at each end the car, two on each side. they are the bolts that have a large washer with markings.

I've another suggestion for the noise. Between the suspension top hat and the car body there should be a very thin piece of plastic. that plastic stops metal to metal contact. Do you remember installing the plastic when you did the dampers?


J
Last edited by aka_juffa on Tue Nov 26, 2013 9:38 pm, edited 1 time in total.
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dmad_dood
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Re: Rear suspension knock

Postby dmad_dood » Tue Nov 26, 2013 9:32 pm

aka_juffa wrote:
dmad_dood wrote:Thats the sound. Like a sort of dull thud metal on metal sound?

Now which are the eccentric bolts? The bolts that to through the bottom of the coilover?

There are 4 eccentric bolts at each end the car, two on each side. they are the bolts that have a large washer with markings.

I've another suggestion for the noise. Between the suspension top hat and the car body there should be a very thin piece of plastic. that plastic stops metal to metal contact. Do you remember installing the plastic when you did the dampers?

J


I did put the plastic spacer on top, i made sure of that.

I no the bolts your talking about but I didnt touch them when i installed the suspension but ill give them a once over in case.
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aka_juffa
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Re: Rear suspension knock

Postby aka_juffa » Tue Nov 26, 2013 9:42 pm

You might not have touched them, but they would have been adjusted for the wheel alignment.

J
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dmad_dood
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Re: Rear suspension knock

Postby dmad_dood » Wed Nov 27, 2013 8:41 am

aka_juffa wrote:You might not have touched them, but they would have been adjusted for the wheel alignment.

J


The wheel alignment was done over a month after the suspension instal. And as soon an i installed the coilovers the noise was happening.

I will still give it a try thou.
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Re: Rear suspension knock

Postby olboy » Wed Nov 27, 2013 9:39 am

Have a look at the sway bar and the coil spring
sometimes the sway bar can slide sideways and touch the coil

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Re: Rear suspension knock

Postby fcruz3r » Tue Dec 03, 2013 6:26 pm

the strut top nut may be loose. Take an ring spanner and torque it down some more. The weight of the car will hopefully not cause the strut shaft itself to turn when your doing this.


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