Hi guys,

I get a knocking noise when driving over bumps/ruts, especially at slow speed. I have an idea it might be the ARB bushes. What do you think?

Adam.

probably bushes or worse shock absorber. i hear that knocking on cold days when going forward an turn the steering wheel on flat road. local mechanic has rise up a car and put a crowbar between something and try to bend. there was no moving, so he say that shock absorbers are probably near death. probably will put some kayaba just-a-gass..

F4ust that sounds like CV joints to me. Hopefully my problem is only bushes. Do you know if they are sold separately or come as part of a component?

It could be your Swing arm Bush, If it is you can either buy the whole arm with the bush in place , or buy a kit and replace the one in the arm you have. If you have ABS i would go for the the kit as the sensor will probably break and that adds a £60 on to the job .

If it's the front it could be the end ARB bush that connect onto the lower swing arm as the ARB is real close and can hit the swing arm on the bump rebound.

It's hard to test for as the ARB is under load when the car is on its wheels and when you jack the car up the bar moves but is still under load so everything feels tight when you have a feel. Look at the end of the bush and you might see some cracks in the rubber or a small gap around the ARB end that goes into the bush.

When the rear swing arm bushes go you can get knocking but more then that the back end of the car feels all over the place when going round corners.

FYI Fiat want to sell the full ARB with bushes (nuts!) but you can find them for sale on ebay.de or from a company on the web.

Rear swingarm bush kits can be found from the link below

link1

Front ARB swingarm bush link below.

Link 2



Hope this helps.
Doc Orange Peel

Nino
How about putting together a Polyflex bush kit for the barchetta? I was at some point going to buy a front swing arm and send it off to them to match up the bushes and then buy a load to sell as a kits. When you buy the upgraded ARB kit for the Barchetta you do get the two inner ARB bushes in Polyflex but the kit never comes with the outer swingarm polyflex bushes !?!

Let me know Nino, I will be the test subject for a Polyflex kit m8.

Thanks everyone for your help, I'll have a closer look today. When you refer to front swing arm, do you mean wishbone?

i get a knocking from my rear end when going over bumps too, which now looking at those links, have identified it as the rear arm ,front bush. When driving and pulling on the handbrake the knocking can be also be heard.

when yr parked with handbrake on, try rocking the B forward and back, if the rear bushes are gone u should see the movement and hear the knock.

just placed an order for new front and rear bushes for the rear swing arms and also the bush and bearing kits from the nice guys at Shop4parts.
Should be the end of my knocking noise, They did say at the store that they sell lots of these for the B so must wear out alot.

Have fun m8

docorangepeel said:

Have fun m8

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It will be my nephew mike who will be doing the f-ing and blinding... if its a difficult job to do.

As long as nothing snaps off it's not so bad but you know Italian cars m8

I changed the rear discs the other day and the locating studs snapped off! It took a lot longer than it should have! Other than that I count on the bolts sheering because it makes removal so much quicker.

I was cornering at 60 today and half way through the bend the car snatched suddenly and almost over steered. I think I should get some advice before it gets dangerous.

When I had stock 15" alloys on my B I used to be able to get lovely lift off oversteer around the large roundabouts on my old companies campus but after changing the shocks and springs and fitting 17" alloys the speed I would need to go before the back end would let go was way to fast for me. When the upgraded ARB kit went on the car felt even more sure footed.

docorangepeel said:

When I had stock 15" alloys on my B I used to be able to get lovely lift off oversteer around the large roundabouts on my old companies campus but after changing the shocks and springs and fitting 17" alloys the speed I would need to go before the back end would let go was way to fast for me. When the upgraded ARB kit went on the car felt even more sure footed.

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Uhhm. Ive got the same spec as you.. LOL . hit a few roundabouts and managed to get her arse out, dred to think what speed i was doing. defo left the other guy chasing me.

i did have a scare the other nite though, had just left from a race meet they have on an unused highway over here on sunday nights. I only spectate but when i got on the motorway to go home, had a run upto high speed in 5th gear and was just about to take this motor when he pulls across my path and i hit the brakes. The B's rear end went out and i drifed across the motorway's two lanes like a snake before gaining control and my heart beat to come down to a safe level. Very scary but exiting at the same time. Can anyone explain why this would happen, should i check my brake bias.

Sounds like as you hit the stop pedal hard the travelling weight all went to the front and the back got all light on you and the rear tyres lost grip, plus with a little sideways movement all got a little white knuckle. Was the petrol tank almost empty as well? You could move the battery to the boot or add some extra ballast in the boot and see if that helps at all.

If I ever get round to fitting the Brembo brake calliper upgrade, I would add a changeable brake bias.

I think my driving style is not at full on as yours KC hehhee :slayer: