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914World.com _ 914World Garage _ shaky suspension ?
Posted by: michelko Nov 1 2005, 10:53 AM
Hi everybody,
have a mysterious suspension problem.
Sometimes on a bumpy road the car is shaking a bit side to side.
Changed the tie rods to turbo style, mounted bump steer kit, adjusted the toe in to factory spec, every screw connection is fastened. what else can i do (check)?
Any body know this problem or the remedy?
I am sure it is not the bump steer problem!!! 
Posted by: Aaron Cox Nov 1 2005, 10:58 AM
was it aligned afterword?
is your car lowered? thus you used a bumpsteer kit?
Posted by: Joe Ricard Nov 1 2005, 11:04 AM
Define shaky. like going over bump in curve and the wheel trys to jerk out your hands. or like shake and shimmy like tire out of balance or wheel bearing loose.
Posted by: michelko Nov 1 2005, 11:15 AM
it feels like the whole front of the car is moving from left to right. fast and short .
Not the shaking steering wheel if the car is lowered to much. The steering wheel is not moving while the symptom is happening.
It is realy hard to explain 
Posted by: lagunero Nov 1 2005, 11:18 AM
lug nuts tight? new tires grabbing grooves of road?
Posted by: SLITS Nov 1 2005, 11:19 AM
Rain grooves in driving surface?
Shitty roads
Poor quality / old tires tracking in ruts / grooves.
Loose wheel bearings
To much toe (neutral or out)
Check rear trailing arm bushings for detoriation..
Check front bushings for same
Posted by: michelko Nov 1 2005, 11:39 AM
tires are new.
wheel bearings not checked till now but no abnormal noise from them.
Toe in adjusted to factory spec 20` (+- 10`)
A-Arm buschings and trailing arm bushing not checked now. How is this done?
Posted by: michelko Nov 1 2005, 11:41 AM
a forgot: anti roll bar in, no difference!
Posted by: goose2 Nov 1 2005, 12:30 PM
shocks?
Posted by: Headrage Nov 1 2005, 12:31 PM
Bent wheel?
Posted by: SLITS Nov 1 2005, 12:54 PM
| QUOTE (michelko @ Nov 1 2005, 10:39 AM) |
| tires are new. wheel bearings not checked till now but no abnormal noise from them. Toe in adjusted to factory spec 20` (+- 10`) A-Arm buschings and trailing arm bushing not checked now. How is this done? |
For rears....put on lift....try to push wheels sideways...watch trailing arm attachment (especially the inner attachement) for movement
For fronts, the same principle...but wheel would move more fore and aft around the torsion bar ends. You would have to carefully watch the attachment points
The wheel bearing check is not noise....it would be rocking the wheel in a vertical plane to see if they were loose....grab top and bottom and try to rock them to see if there is any movement about the spindle.
Hey, we're guessing here.
You said the steering wheel doesn't shake...you said the car darts back and forth while holding a straight line.... Please correct me if I am wrong......
Posted by: Joe Ricard Nov 1 2005, 01:06 PM
Yea, I agree now it sounds like you need to go inspect stuff.
I bet loose wheel bearings
followed by worn suspension: shocks, bushings or mounting points in that order.
Posted by: Thorshammer Nov 1 2005, 01:32 PM
How wide are the front wheels and where is the caster set at???
Erik
Posted by: r_towle Nov 1 2005, 04:55 PM
I chased a shimmy for quite a while...
I changed everything...
I found two things.
First was the bottom of the strut tube where the ball joint is installed, the round hole that the ball joint slides into was out of round...this created a wobble .
The second was simple, but annoying.
The rear of the torsion bars has a felt washer over it. It ensures that the torsion bar stays centered.
Well, after 30 years, the felt is gone...I replaced it with a rubber washer. This stopped the clunk.
Rich
Posted by: michelko Nov 1 2005, 11:33 PM
| QUOTE (SLITS @ Nov 1 2005, 10:54 AM) | ||
For rears....put on lift....try to push wheels sideways...watch trailing arm attachment (especially the inner attachement) for movement For fronts, the same principle...but wheel would move more fore and aft around the torsion bar ends. You would have to carefully watch the attachment points The wheel bearing check is not noise....it would be rocking the wheel in a vertical plane to see if they were loose....grab top and bottom and try to rock them to see if there is any movement about the spindle. Hey, we're guessing here. You said the steering wheel doesn't shake...you said the car darts back and forth while holding a straight line.... Please correct me if I am wrong...... |
Yes there is a little play if i rock the wheel in vertical.
But i thought it´s normal my BMW makes the same thing and hasn´t the shaking.
And yes, the steering wheel is stady, it is the body of the car that is moving from side to side (not front to rear).
btw. thanks for all the tips. much work for the next weekend
Posted by: michelko Nov 13 2005, 01:58 PM
After some inspection of the suspension parts, changing (again) the shocks, allignement, wheel bearing etc. i can´t find anything wrong with the mechanic, so i think its a problem of the tub itself.
I read about a mercedes cabrio that made this shaky also when driving over a railway crossing.
I purchased the Engmann-kit months ago, i will mount it over the winter.
I am in the hope that this will cure the problem.
Unfortunately i don´t know any other running 914 in the area to take a test drive .
Posted by: r_towle Nov 13 2005, 05:41 PM
vertical wheel shake on the front tires is the ball joint.
Have a friend shake the wheels while you feel the bottom of the strut tube...it was really hard to find, and really hard to feel, but a little wobble or shake in the lower ball joint will be drastic on the road...
Rich
Posted by: Spoke Nov 13 2005, 10:31 PM
Had the wandering thing also. Tie rod ends were shot, replaced with turbo tie rods, wandering reduced but not gone. Checked front end by jacking up one side at a time, and grabbing the wheel, shake back and forth, up and down and found out the ball joints were bad.
After new ball joints, things got much better, but still had some play which was from the wheel bearings not being tight enough. Tightened the bearings and now the car is nice and tight.
Spoke
Posted by: michelko Nov 14 2005, 12:30 PM
| QUOTE (Spoke @ Nov 13 2005, 08:31 PM) |
| Had the wandering thing also. Tie rod ends were shot, replaced with turbo tie rods, wandering reduced but not gone. Checked front end by jacking up one side at a time, and grabbing the wheel, shake back and forth, up and down and found out the ball joints were bad. After new ball joints, things got much better, but still had some play which was from the wheel bearings not being tight enough. Tightened the bearings and now the car is nice and tight. Spoke |
maybe that balljoint way is something i could try out bevore i throw it away
. they are not too expensive.
Posted by: Eric_Shea Nov 14 2005, 12:39 PM
Hey Rich... Check this out!
I agree with Rich. This is a problem that Porsche has recognized and posted in their Upfixen series. Early ball joints can wallow out the bottom of the strut causing exactly what you are describing.
Also, sounds like you need to either tighten or replace your wheel bearings based on this comment...
| QUOTE |
| Yes there is a little play if i rock the wheel in vertical. |
Posted by: michelko Nov 16 2005, 11:29 AM
purchased already a set of new wheel bearings. This weekend i willl check/replace the ball joints.
Posted by: Brotherbob Nov 16 2005, 11:36 AM
I would mount the rear tires on the front and front on the rear and drive it.
Nothing changes nothing lost , no money spent?
Then start throwing around parts money, wheel bearings, ball joints, etc.
my 2 centavos.
Posted by: michelko Nov 17 2005, 06:13 AM
| QUOTE (Brotherbob @ Nov 16 2005, 09:36 AM) |
| I would mount the rear tires on the front and front on the rear and drive it. Nothing changes nothing lost , no money spent? Then start throwing around parts money, wheel bearings, ball joints, etc. my 2 centavos. |
I have this shaky feeling since i bought the car.
It was fitted with 41/2" Steel Wheels with gigantic 165 winter-Tires, now 51/2 wheels with 185 summer-tires : no change
totaly shot boge shocks allaround, now new koni: no change
rusted through hell hole and rocker, now complete solid tub: no change
old standard tie rods, now new turbo-tie rods: no change
different toe in settings tested: no change
Things to check or change:
Ball-joints
wheel bearings
A-Arm bushings
Will do this next weekend
Posted by: Bill Kohnke Nov 17 2005, 06:56 AM
Is the car a 1970?
I chased what I thought was a caster shimmy for months. It was at 50 to 55 mph. And some shaking also. This was after moving up to 205/50 tires. I finally changed out the front struts and ball joints to a 74 models. The hubcentric feature fixed the problem.
Bill Kohnke
Posted by: MecGen Nov 17 2005, 07:17 AM
Hey hey
Lots of good advice here...I have personaly seen an early 914 lower ball joint wobble in its socket....
My 914 had a bitch of a "sideways" wobble after hitting a railway track at an angle...my new Koni's diddn't fit quite right in the tube or loose in its own insert, 6 and 12 oclock movement when the car was jacked and shock fully extended. Switching to Boge fixed this. in the ass end my trailing arm bushings were OK but took them apart anyways...good thing, my near pearfect car had rust on the inside shafts so deep the rubber bushing where just being squished around...
These 2 things made all the differents in the car, very hard to check and find.
Ich liebe Ihr Auto 
Later
Posted by: michelko Nov 17 2005, 11:52 AM
| QUOTE (Bill Kohnke @ Nov 17 2005, 04:56 AM) |
| Is the car a 1970? I chased what I thought was a caster shimmy for months. It was at 50 to 55 mph. And some shaking also. This was after moving up to 205/50 tires. I finally changed out the front struts and ball joints to a 74 models. The hubcentric feature fixed the problem. Bill Kohnke |
Yes it is a 1970 car.
I am looking for a 5 lug conversion. Only missing parts are new break calipers.
Don´t know if try first with new ball joints or buy new 911 calipers and 2 more fuchs and do the five lug now
ball joints are cheaper.
BTW Thanks for all the good advices. I love the Club!
Posted by: brp914 Nov 17 2005, 11:39 PM
My '70 had the exact symptom yours has, and just like everyone here has mentioned, the ball joint was loose in the strut. New later style struts using the wedge pin solved the problem. But I wanted to mention a couple things that I've read here that I disagree with. First, I cant believe the problem is in the tub. After the work you did restoring it, you probably the most solid tub on the planet. Second, people have suggested tightening the wheel bearings as a means of removing play. I think that is dangerous. Front bearings are tightened to 1 ft-lb (please do the N-m conversion). If they are still loose then the bearings and/or spindle is worn and should be replaced. Overtightening the bearings risks disaster. Feel for a groove on the under side of the spindle. good luck
Posted by: michelko Nov 28 2005, 01:22 AM
Hi everybody,
thhis weekend i did some improvements on the front suspension.
I changend the ball joints and the wheel bearings.
As they looked, they were the first ones. Original mounted in Stuttgart 
Opening the nuts that hold the ball joints was areal disaster
With the right tool an an impact wrench a 1/2 hour of work....
nothing happened.
Weapons of choice:
Attached image(s)
Posted by: michelko Nov 28 2005, 01:24 AM
then i decided to grind out the big nuts with a dremel. Fortunately i bought a set of that stupid nuts time ago.
Attached image(s)
Posted by: michelko Nov 28 2005, 01:28 AM
old stuff
Attached image(s)
Posted by: michelko Nov 28 2005, 01:29 AM
and the new ones
Attached image(s)
Posted by: michelko Nov 28 2005, 01:29 AM
driver side
Attached image(s)
Posted by: michelko Nov 28 2005, 01:30 AM
and after half an hour of grinding
Attached image(s)
Posted by: michelko Nov 28 2005, 01:31 AM
the new one in
Attached image(s)
Posted by: michelko Nov 28 2005, 01:36 AM
after a short testdrive i decided to change the wheel bearings also.
Unfortunately no pics of that work.
The shaky was a mix of a bunch of worn parts. Every step (Tierods, Ball joints, wheel bearings) made cured the shaky a little more.
Couldn´t do extensive test driving because of snow
but till now this is an complete different car now.
Posted by: maf914 Nov 28 2005, 08:09 AM
| QUOTE (michelko @ Nov 27 2005, 11:22 PM) |
| Opening the nuts that hold the ball joints was areal disaster With the right tool an an impact wrench a 1/2 hour of work.... nothing happened. Weapons of choice: |
Where did you get the tool for removing the ball joint nut? I think this is the first time I have seen the "special" tool, other than in my Haynes manual. I remember the one Dave Hunt made up from pipe fittings.
I used an adjustable pipe wrench to remove them on my car.
Posted by: michelko Nov 28 2005, 08:32 AM
| QUOTE (maf914 @ Nov 28 2005, 06:09 AM) | ||
Where did you get the tool for removing the ball joint nut? I think this is the first time I have seen the "special" tool, other than in my Haynes manual. I remember the one Dave Hunt made up from pipe fittings. I used an adjustable pipe wrench to remove them on my car. |
i bought it from guy that is remanufacturing several parts, like tools, suspension bearings, caster shims, etc.
I bought it before i saw the idea with the pipe fittings, on the other side 20 Euro are not to much for this rare tool
Also on german ebay those tools appear from time to time.
Unfortunately in my case the tool doesn´t help anything to remove the nuts.
For torquing down the new nuts it was very helpfull.
Posted by: Aaron Cox Nov 28 2005, 10:44 AM
where do you get your parts? do you go down to mittelmotor?
Posted by: michelko Nov 28 2005, 12:45 PM
| QUOTE (Aaron Cox @ Nov 28 2005, 08:44 AM) |
| where do you get your parts? do you go down to mittelmotor? |
Yes sometimes. But i have some .. lets say not so good experiences with them.
So i try to find my stuff at other dealers. There is one called "914 Ersatzteile Versand".
Only the best experiences, ultra fast shipping, good prices.
Some parts are direct from Porsche. In Mannheim, 30km away there is an porsche agency.
Ebay is also a good source for new and almost used parts. It´s in the mix.
Posted by: michelko Mar 24 2006, 05:12 AM
Hi guys,
think i found the problem.
excesive low ride! There are some rubber pieces mounted n the struts.
there was to less room for the strut to move free if i hit a little larger bump. I turned the spindels higher an made a test drive. Nearly now shaky anymore 
But now the car looks like a stork
Maybe the rubber things can be cut a little?
Posted by: sj914 Mar 24 2006, 06:06 AM
The bump stops. Are they the solid ones or the ones that look like three donuts stacked on top of each other?
Posted by: michelko Mar 24 2006, 08:35 AM
| QUOTE (sj914 @ Mar 24 2006, 04:06 AM) |
| The bump stops. Are they the solid ones or the ones that look like three donuts stacked on top of each other? |
bump stops... the right description. yes the donuts.
Posted by: rhodyguy Mar 24 2006, 10:31 AM
brad told me to cut the bump stop in half. liberal ammounts of penetrant, and your air chisel placed in one of the tangs on the capturing nuts, will run the nut off in 15 seconds. prob less. using a dremel seems like a bunch of work. for others that haven't done this, loosen the nut but leave it on. this makes it easier to pull the top of the ball joint out of the strut tube after you remove the bolt.
k
Posted by: Dr Evil Mar 24 2006, 10:38 AM
I use a pipe wrench and then put gobs of anti sieze on my ball joint at the nut when installed.
Posted by: DEC Mar 24 2006, 10:51 AM
Michael,
call me 
Phone number is locate on my homepage 
Is very difficult to explain this phenomenon.
Wilco
Posted by: SirAndy Mar 24 2006, 11:43 AM
| QUOTE (michelko @ Mar 24 2006, 06:35 AM) |
| bump stops... the right description. yes the donuts |
are they the 3-piece ones? what brand are your shocks?
you should be able to cut 1/3 for sure, on any brand shock. on some, up to 2/3 ...
here's what i did:
jack up the front, unload the suspension, remove top nut, remove bump stop rubber, press the shaft all the way into the shock until it hits the bottom, mark the shaft where it enters the shock.
remount shock (don't forget the bump stop). once the shock is fastend, the distance from the top sheetmetal to the mark on the shaft is the absolute minimum of rubber you have to leave on the bump stop.
you should actually leave a bit more as the rubber compresses. the mark is where the shock will bottom out internally and if that happens, your shock will break.
this way, you get a really good idea on how much of the bump stop you can cut off, regardless of the brand of your shocks ...
AndyPS: makes any sense? if you want, i can repeat it in german ...
Posted by: michelko Mar 25 2006, 12:25 AM
| QUOTE (SirAndy @ Mar 24 2006, 09:43 AM) | ||
are they the 3-piece ones? what brand are your shocks? you should be able to cut 1/3 for sure, on any brand shock. on some, up to 2/3 ... here's what i did: jack up the front, unload the suspension, remove top nut, remove bump stop rubber, press the shaft all the way into the shock until it hits the bottom, mark the shaft where it enters the shock. remount shock (don't forget the bump stop). once the shock is fastend, the distance from the top sheetmetal to the mark on the shaft is the absolute minimum of rubber you have to leave on the bump stop. you should actually leave a bit more as the rubber compresses. the mark is where the shock will bottom out internally and if that happens, your shock will break. this way, you get a really good idea on how much of the bump stop you can cut off, regardless of the brand of your shocks ... AndyPS: makes any sense? if you want, i can repeat it in german ... |
Hi Andy,
nice description. No need to say it in german again
I will try this after some more testdriving. Just to be sure it was the real problem.
Shocks are Boge but i also tryed adjustable Koni red. there was no major difference in the behavior.
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