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sixaddict
Car was aligned and corner balanced .....At track discoverd 3 bolts attaching @ front of trailing arm were "tight" yet arm was shifting. So bolts are tight but arm sliding back and forth....Really "interesting" under heavy braking after high speed straight...... evilgrin.gif
I am sure someone can tell me what is up and how to fix..
Thanks
Terry
Eric_Shea
Do you have the proper Schnorr washers under the bolt head?
pcar916
Shims (washers) between the arm and it's mount until it won't move laterally any more.
sixaddict
Eric:
Good possibility they are not there...but frankly not sure.
Is this a Porsche only part. Does it in any way impact ability to get negative camber because it was apart to be aligned
Thanks
Terry

QUOTE(Eric_Shea @ Sep 21 2012, 10:02 AM) *

Do you have the proper Schnorr washers under the bolt head?

pcar916
Just to ask if I'm I understanding right, is the arm moving side-to-side between the mount points?
Jgilliam914
QUOTE(pcar916 @ Sep 21 2012, 01:10 PM) *

Just to ask if I'm I understanding right, is the arm moving side-to-side between the mount points?


That or the rear suspension points are flexing?
ChrisFoley
QUOTE(sixaddict @ Sep 21 2012, 11:53 AM) *

Car was aligned and corner balanced .....At track discoverd 3 bolts attaching @ front of trailing arm were "tight" yet arm was shifting. So bolts are tight but arm sliding back and forth....Really "interesting" under heavy braking after high speed straight...... evilgrin.gif
I am sure someone can tell me what is up and how to fix..
Thanks
Terry

There is something keeping the bolts from tightening against the underside of the bracket. Perhaps the bolts were changed and have too long an unthreaded shank, or there is something inside the threaded hole (possibly rust or dirt) causing the bolt to tighten up before its fully against the bracket.
There should be a 3 hole plate between the bolt heads and the console bracket. Is that there still?
Who did the alignment? Did they use the correct shims? How many shims are in there? Has someone previously "fixed" a broken bolt issue on your car?
Shnorr washers are important to keep the bolts from loosening but that doesn't sound like your problem.
toolguy
Pull out 1 bolt, measure the depth of the hole it's going in compare to the bolt. .
The cheating fix is add a shim plate on top of the factor top plate but I'd only do that as a temp thing. . on older 914 the bolt hole went all the way through. . I seem to recall that later cars they didn't. . if that looks all ok, amybe there is wear problems in the pivot bushings

Jack up the car, grab the wheel and see which way it wiggles. . . I'd look at the ears for elongated holes, the inner ear is cracked and flexing, or the bushings are worn out. .

When you cant' see the trouble, you'll need to pull it apart. . unfortunately that mean loosing the alignment settings. . and if any of those things are worn, it will need realignment anyway.
Eric_Shea
QUOTE
Shims (washers) between the arm and it's mount until it won't move laterally any more.


That would change his camber.

Chris is on to something; There is supposed to be a plate under the bolt heads. It's rather thick. If it's missing the threaded portion of the fastener could be bottoming out prior to the assembly being tightened properly.
sixaddict
Yep...I thought Chris may have hit on it too.
Will post when we get it figured out.
Thanks
Terry

QUOTE(Eric_Shea @ Sep 21 2012, 12:46 PM) *

QUOTE
Shims (washers) between the arm and it's mount until it won't move laterally any more.


That would change his camber.

Chris is on to something; There is supposed to be a plate under the bolt heads. It's rather thick. If it's missing the threaded portion of the fastener could be bottoming out prior to the assembly being tightened properly.

bulitt
Bolts should be 10mm x 55mm x 1.5 thread. They bolt into the three threaded tubes welded into the front outer control bracket.
Is it possible the threads stripped and someone just put bolt(s) through the tubes with a nut on top?

Here is the plate Chris is talking about.
Click to view attachment

sixaddict
Chris was right ...Bolts were too long
Thanks all

beerchug.gif


QUOTE(bulitt @ Sep 22 2012, 05:46 PM) *

Bolts should be 10mm x 55mm x 1.5 thread. They bolt into the three threaded tubes welded into the front outer control bracket.
Is it possible the threads stripped and someone just put bolt(s) through the tubes with a nut on top?

Here is the plate Chris is talking about.
Click to view attachment

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