Top shock mount torque and bushings on NB

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samx5
Fast Driver
Posts: 172
Joined: Tue Feb 24, 2009 10:59 am
Vehicle: NB8A
Location: Radelaide SA

Top shock mount torque and bushings on NB

Postby samx5 » Wed Apr 11, 2012 1:58 pm

I've noticed that the rubber bushes in the top shock mounts on the front of my car are squashed down pretty hard, so much that they have many small splits in the rubber. The washer on top has also distorted due to being tightened. I'm after some advice on the following:
Should the recommended torque setting for the top shock bolt (whatever it is) cause the rubber top bush to squash down significantly and also cause the washer to be squashed, or has the bolt been done up too tight?
The rubber bush is probably perished to some degree, causing the small splits. Are these rubber bushes meant to retain some compression in them (i.e., not be too tight) so they assist in ride quality and noise suppression over bumps?
If the rubber bush is on the way out, I'll probably order a set of replacement top mounts.
I've also had a persistent knocking from the rear on one side, its been narrowed down to the shock itself (without removing the shock from the car, just process of elimination on what is tight & what is loose). The Koni Yellows in the car have only done 6,000km, & I'm starting to think that maybe the mounts have not been done correctly in the rear as well. It was noted when the shocks were installed that there was a little bit of vertical free play in the shock shaft from full extension, I don't know if that is normal or not as the shaft will not be at full extension with the weight of the car on top - happy to stand corrected.
I'll try to get a close-up piccie & post up, in the meantime all assistance appreciated.
Was: 1988 Corolla 4A-GE Twin Cam, 1991 Laser TX3, 1995 Peugeot 306 S16, 2003 Astra Sri Turbo, 2007 SP23 Lux
Now:1999 NB8A, 2011 Outlander VR-X

RJ45
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Location: Lane Cove

Re: Top shock mount torque and bushings on NB

Postby RJ45 » Wed Apr 11, 2012 2:59 pm

I also had a knocking from the rear, felt like the car was about to explode if driving on anything but smooth roads.

Turned out that the captive nut in the lower arm, that the lower shock bolts into had broken off.
I drove around on it too much, as I was too busy to get it fixed, and ended up snapping the bolt.
But the bolt did stay in place so was still able to take it to a suspension shop to sort.
NB8C+PSS9

samx5
Fast Driver
Posts: 172
Joined: Tue Feb 24, 2009 10:59 am
Vehicle: NB8A
Location: Radelaide SA

Re: Top shock mount torque and bushings on NB

Postby samx5 » Wed Apr 11, 2012 6:46 pm

Thanks RJ, yeah the bottom bolts have already been checked, as have sway links etc...... the only thing left is the top mounts or the shock body itself.
Was: 1988 Corolla 4A-GE Twin Cam, 1991 Laser TX3, 1995 Peugeot 306 S16, 2003 Astra Sri Turbo, 2007 SP23 Lux
Now:1999 NB8A, 2011 Outlander VR-X

samx5
Fast Driver
Posts: 172
Joined: Tue Feb 24, 2009 10:59 am
Vehicle: NB8A
Location: Radelaide SA

Re: Top shock mount torque and bushings on NB

Postby samx5 » Wed Apr 11, 2012 7:44 pm

Update, see attached photo of front shock top mount:
http://s715.photobucket.com/albums/ww153/biante27062/?action=view&current=Shocktopmountresize.jpg
Note the splits in the rubber and the deformed top washer.
Was: 1988 Corolla 4A-GE Twin Cam, 1991 Laser TX3, 1995 Peugeot 306 S16, 2003 Astra Sri Turbo, 2007 SP23 Lux
Now:1999 NB8A, 2011 Outlander VR-X

RJ45
Fast Driver
Posts: 107
Joined: Wed Feb 16, 2011 5:55 pm
Vehicle: NB8B
Location: Lane Cove

Re: Top shock mount torque and bushings on NB

Postby RJ45 » Thu Apr 12, 2012 9:50 pm

Just in case you wanted something to compare to, pic is from my old shocks 2003 NB with 86K
http://s1057.photobucket.com/albums/t39 ... nb_top.png
NB8C+PSS9

project.r.racing
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Location: Glasshouse Mountains, QLD

Re: Top shock mount torque and bushings on NB

Postby project.r.racing » Fri Apr 13, 2012 9:31 am

Recent thread about same subject...
viewtopic.php?f=30&t=52189

samx5
Fast Driver
Posts: 172
Joined: Tue Feb 24, 2009 10:59 am
Vehicle: NB8A
Location: Radelaide SA

Re: Top shock mount torque and bushings on NB

Postby samx5 » Fri Apr 13, 2012 12:12 pm

Thanks RJ & PRR, good info.
Was: 1988 Corolla 4A-GE Twin Cam, 1991 Laser TX3, 1995 Peugeot 306 S16, 2003 Astra Sri Turbo, 2007 SP23 Lux
Now:1999 NB8A, 2011 Outlander VR-X


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