HELP! My baby has got suspension problems!

Geronimo '74 · 09-22-2003, 03:23 AM

Hello everybody,

I desperately need some help fixing the front suspension on my 911 '74 coupe (see also in owners gallery).
Whenever I encounter a small bump or hole in the road, I hear a strange sound (like, er.., "klonk"...) coming from the front suspension (left more than right). I think the sound (like two hard things colliding) comes from my Koni shocks (red ones). My car has been lowered in the front and I use 205/50 tyres (15 inch fuchs) So it would seem possible to me that my shocks are maxed out (or maxed IN, depends on the way you look at it) While turning the sound is there even without noticeable bumps or holes.
Can you guys give my some advice about this because it's taking a lot of fun out of my rides (not all the fun though...)

Geronimo '74

Tim Walsh · Tim Walsh's Garage

If your suspension hasn't been gone through in 30 years I'd sugest that first. Replace all your bushings, tie rods, ball joints and probably shocks as well. It's like night and day when it's all done. That's next on my list after my engine's back in the car.

jpnovak · 09-22-2003, 05:57 AM

Check to make sure your wheel bearings are correctly tightened. Next would be ball joints and tie-rods. I would also check to make sure that the strut insert has not come loose in the housing. Support the car on jackstands and wiggle things. You may just isolate the clunk.

Of course, Tim's suggestions go right along with the general suspension maintenence after 30 years.

Superman · 09-22-2003, 06:39 AM

Your front torsion bars are probably banging against the control arm because the bushings are sagging. I agree that the front suspension should be disassembled and inspected. It's not really that hard to disassemble. Replace those bushings, and the front will be quiet as a mouse.

Geronimo '74 · 09-22-2003, 11:17 PM

Thanks a lot for the advice!
Will be helping my mechanic with the disassembly soon.
Can anybody tell me if it would be better to change all four shocks or should I just keep it with the ones in the front? (Will go for Koni again, Bilsteins might be a bit too stiff for mostly road use, if I'm wrong, please correct me.)
Anyway, thanks again for the enlightenment.
Geronimo '74

dickster · 09-23-2003, 12:31 AM

jamie

i have the same thing. one of my (fairly) new fronts has come loose and bangs when i go over bumps.

Jeroen · 09-23-2003, 02:53 AM

Hey Geronimo,

If you replace the front shocks, do the rears as well
You might wanna consider the yellow adjustable Koni's

Bilstein Sports are too much for a car with stock torsionbars IMO, but you could use Bilstein HD's (which are softer than the sports)

Basically it comes down to what type of struts are on your car, and since you said you already have Koni's, I'd stick with them

Check all rubbers/bushings in the suspension while you are at it.
Those were all pretty much desintegrated on my '87 Carrera (with approx. 230K km's of abuse)

cheers,

Jeroen

Chuck Moreland · 09-23-2003, 07:59 AM

Quote:

Originally posted by Superman
Your front torsion bars are probably banging against the control arm because the bushings are sagging. I agree that the front suspension should be disassembled and inspected. It's not really that hard to disassemble. Replace those bushings, and the front will be quiet as a mouse.

If you don't find a loose part, this is likely the problem.

The torsion bar rubs against the ID of the control arm, making noise and scraping off the protective paint. Be sure to inspect the torsion bar for damage. Rust will ruin the tbar if you don't catch it early.

Geronimo '74 · 09-23-2003, 09:29 AM

Thank you all very much for helping me in this. I am new at this and it is a pleasant surprise to get so much help from my recently acquired pelican family members. I hope that I will be able to help other people one day as well (for now, I'm still somewhat of a novice)
I do have another question now though. If one of the front suspension bars needs to be replaced, should I replace the other ones (all 4) as well?
And if I change them, should I replace them with ones that have the same specifications knowing that I will probably be installing yellow Koni sport shocks?
Greetz,
Geronimo '74

Geronimo '74 · 09-23-2003, 09:31 AM

I mean TORSION bars of course instead of suspension bars...

FrdzRed · FrdzRed's Garage

Had the same sound in my car, especially when going over bumps while turning. It ended up being the steering rack. The bearings/bushings in the ends of the housing worked loose and the rack would rattle inside the housing since the bearing was not centering it.

Jeroen · 09-23-2003, 01:22 PM

IF you need to replace a torsionbar, it would be best to do them in pairs at least (both fronts and/or both rears), since they've been there for quite some time already
Chances are pretty big that the old and new bar would have different springrates

For the same reason, I would replace all four, but that's just me...

This may also be a good time to consider bigger torsionbars (if that's your kinda thing)

cheers,

Jeroen

Geronimo '74 · 09-23-2003, 10:27 PM

Steering rack hey, will have to check that as well then. I was so focused on the suspension that I didn't even consider the steering part.
Jeroen, if I take bigger torsion bars, then my ride will become harder, no? Would that be necessary? I don't use my car on the track. I'm a sporty driver, not a race pilot. BTW, where are you from in the Netherlands? I live in Mol, near Turnhout (below Eindhoven)
Greetings
Geronimo '74

Jeroen · 09-24-2003, 12:05 AM

Hey Geronimo,

Yes, bigger torsionbars are stiffer springs. But they are available in several gradiations.

I'm from Hellevoetsluis, which is about 30km south/east of Rotterdam

You might wanna check these BBS-es
http://www.prikpagina.nl/list.php?f=830 some guys there are organising a drive this saturday that starts near Eindhoven.
http://www.porscheforum.nl is still fairly new so there isn't much traffic yet.

cheers,

Jeroen