Knocking Noise suspension - Upper control arms or steering rack?

[bix]

I replaced the ARBs with Eibach unit which come with PU bushes. They don't come with clamps/collars, so there is a bit of hacking involved.

By the way, the old man never seemed too concerned with the knocking and squeeking coming from the XA Falcon, so I was wondering if Alfa Romeo owners fit any of the following profile:
1. Perfectionists
2. Sensitive new age types
3. Pure anal

[lmcpaulm]

Thanks for confirming the bolts bix.

Sounds like the front ARB to me (sway bar).

Looks like the ARB will be next on the list then....

By the way, the old man never seemed too concerned with the knocking and squeeking coming from the XA Falcon, so I was wondering if Alfa Romeo owners fit any of the following profile:
1. Perfectionists
2. Sensitive new age types
3. Pure anal

Probably a combination of 1 and 3. Once you've had an Alfa that drives like perfection it's your aim to get it back to that point again! 

[Evan Bottcher]

Probably a combination of 1 and 3. Once you've had an Alfa that drives like perfection it's your aim so get it back to that point again! 

Reminds me of the Clarkson quote: "Alfa's were built to be the best cars in the world.....briefly".  Always searching for that perfection again?

[bix]

Thanks for the confirmation lmcpaulm. I reckon I'm a 1 & 3 as well - probably from being tortured my entire childhood in the back of an XA Falcon!

[lmcpaulm]

Happy to report I believe I have now tracked down the problem. 

I thought to myself that the knocking it coming from my heels (and I can feel it) on both sides and the only thing that runs across there is the ARB/Sway bar. So I read on another site if you want to test if it's the sway bar, you take the droplinks off... therefore there's no pressure on the sway bar or anything pulling on it when the suspension is going up and down over bumps. So took them off, have driven it around for 2 days and NO clunking noise!

--> one end of the the sway bar needed to be tied out of the way using some wire as once the droplinks were taken off, both arms of the bar just flopped down.

So it appears;
1. It is either the droplinks themselves (which I highly doubt as they are brand new and Alfa genuine parts); or
2. The sway bar which will need to be replaced.

I'm hoping that if I buy the Alfa replacement sway bar, that it will be a somewhat improved version so this doesn't start up again in 12 months!

It is interesting to note that I have found no real noticeable change in handling with the droplinks off

[L4OMEO]

Hi again

Glad you're making progress, and good process of elimination.

I agree - it's hard to believe it's the links themselves since they're brand new and genuine, although it wouldn't hurt to double-check the genuinicity (is that a word) of them since after-market drop-links are notoriously problematic even from new. I've never inspected one closely so I don't know if they have a part number stamped on them, but check for this, and make sure the Alfa Romeo box it came in isn't branded "Arfa Lomeo' 

I also find it hard to believe it's the bar itself. I mean, it's a bar, a bent bit of metal. Unless it's physically broken, how can it clunk? As I mentioned in my last PM, I still think the front bar bushes could be the cause - if they're slogged out then the bar could move (or clunk) around. This would stop if the droplinks were disconnected, so at this stage you haven't yet eliminated this particular possibility. The front bushes are a known problem, I have yet to hear of someone who had problems with the bar itself. Worth checking.

The bar was never uprated to an improved version to my knowledge and I believe was the same part throughout the model run. You can install an uprated bar off a GTA, or an even more uprated one still from Eibach, but you would need replace the rear bar with one that matches. If you do decide to replace the front bar, you should change the bushes regardless. Bit of a painful job as the subframe needs to be dropped - not difficult, but bank on maybe 3 hours labour from a mechanic.

Interesting your comments on the handling not changing. I think with front-drive cars the rear bar is generally the one that does the lion's share of the work, so if you disconnected that then you might notice a greater difference. From memory, the standard 156 bars were 14mm front/22mm rear, but wankski or colcolcol may correct me there!

Good to see you're nearly there, and looking at a fairly cheap fix. Keep us posted.

Cheers
Rory

[lmcpaulm]

I also find it hard to believe it's the bar itself. I mean, it's a bar, a bent bit of metal. Unless it's physically broken, how can it clunk? As I mentioned in my last PM, I still think the front bar bushes could be the cause - if they're slogged out then the bar could move (or clunk) around. This would stop if the droplinks were disconnected, so at this stage you haven't yet eliminated this particular possibility. The front bushes are a known problem, I have yet to hear of someone who had problems with the bar itself. Worth checking.

Apologies - didn't mean to mislead. You're right it is the bushes. However, the sway bar comes with the bushes attached (like the wishbones), so I will just have to replace the whole bar with a new bar which will have new bushes on it. From what I understand, if the bushes around the bar are worn/split they will just be knocking up and down inside the metal bracket that's fixed to the frame. Removing the droplinks released the pressure on the bar though, so over bumps it's probably still vibrating but not with the force it was before. (I still haven't heard any noise over the last 4 days )

I won't be wasting money having the old bushes burnt off and new ones soldered on - I heard the job is a pain... So I'll just buy a new bar I suppose.

My Alfa Specialist has said since I've had so much work done he will do the job at 1/2 price which will save me some $$$!

Thanks for your help - much appreciated.

[L4OMEO]

Apologies - didn't mean to mislead. You're right it is the bushes. However, the sway bar comes with the bushes attached (like the wishbones), so I will just have to replace the whole bar with a new bar which will have new bushes on it. From what I understand, if the bushes around the bar are worn/split they will just be knocking up and down inside the metal bracket that's fixed to the frame. Removing the droplinks released the pressure on the bar though, so over bumps it's probably still vibrating but not with the force it was before. (I still haven't heard any noise over the last 4 days )

I won't be wasting money having the old bushes burnt off and new ones soldered on - I heard the job is a pain... So I'll just buy a new bar I suppose.

My Alfa Specialist has said since I've had so much work done he will do the job at 1/2 price which will save me some $$$!

Thanks for your help - much appreciated.
[/quote]

Hi

Yeah your description is on the money, that sums it up well. But, the bushes for the sway bar aren't exactly like those on the wishbone and they can be changed. They are installed within the mounting brackets which are indeed welded together, so you can't just open the bracket a bit to pop them out. However, it's an easy job to drill the brackets out to open them, take out the old bushes and install new replacements, and reassemble. When I had mine done I can't recall if the brackets were welded back together, or soldered, or bolted, but it was all included in the 3-hours labour from a non-Alfa but competent mechanic.

I guess where I'm coming from is - if you're going to replace the bar & bushes together you'll have to buy brand new, because if you just get a second-hand one then how do you tell how long the second-hand bushes are going to last before you have this problem again? On the other hand, sourcing the bushes alone is easy and cheap, and installing them as noted above is quite straight-forward.

Sorry I didn't take pics of mine as it was done, would have illustrated this nicely. Worth searching on alfa156.net now you have drilled down to the root cause, may be pics of the sway bar/bushes/brackets there.

Cheers
Rory