vibration

[Tafi]

i am getting a vibration at about 2000rpm. it is in every gear. it is not the wheels as i have had them balanced.
the one thing that springs to mined is the prop, as it happends at the same rpm in all the gears.

please help as it is starting to get to me.

Tafi

if you need more info, please ask

[fgc]

Hi Tafi,

sorry to hear that... I have the same problem too and its around 2000 rpm too in every gear except 1 (perhaps the prop isnt spinning as fast at 2000 on 1?)

I know how annoying it can be.. hope you find the cause and I would love to hear about it too.

fgc
67 spider

[Roadtrip]

If it's only at a single rpm of the engine , then I'd look for something loose that's causing a resonate vibration. The first thing I'd look at are the heat shields of the front and center mufflers. That front one expecially can make an awful racket and vibration if it's loose.

[tokky28]

Yeah, I remember having a similar problem in the past, I don't know if it was in the same rpm range, but I got the front heat shield tacked down and the noise was gone with the wind.

Andre

[Tafi]

thanks for your help. i will have a good look tomorrow.


Tafi

[alfist]

I also have an exactly same problem. It's very annoying and ruining my summer ride...

It happens during deceleration (maybe acceleration too, but I don't notice) and 4th gear is most noticeable (2000-2500RPM).

My friend will do something this week.

Let's keep in touch till the problem is solved!

I started the thread for this almost 2months ago, but it's gone...Maybe it got lost when the server had the problem.

[Lance G]

Please let me know if anyone has had any luck solving this problem?

[Antiacus]

Mine was the heat shield over the cat...

[Lance G]

Mine is a '74 without that heat sheild. My dad has an '86 with the heatsheild exhaust manifold problem. His Alfa mechanic fixed it with a couple of hose clamps on the exhaust manifold.

I still think my problem is u-joints, just need to get it taken care of.

[AlfaRomeo1750]

Hello every one,

With regard to your vibration, my two cents are to check for worn motor mounts. As the engine revvs it does move slightly in the direction with which the crank turns, when you have worm mounts the tilt can be excessive especially under load.

If you have a pan guard, this is one place to check for a vibration point, perhaps it is the exhaust touching as the engine moves... what ever the cause check if the engine is secure first... then work your way back.

Just my two cents..

Regards

Martin

71 Spider Veloce
81 GTV6
87 Quadrifoglio
93 164 S

[boggissimo]

When you say vibration, is it one you can feel, or just hear?? Does it happen if you rev the engine in neutral too, or does it only happen when you're in gear?

I have had a couple of vibration things in my Spider, one was a loose fitting in the air intake tube, and the other was a buggered catalytic converter with loose bits inside it - the rattles happened at characteristic RPMs because that happened to be some sort of resonant frequency of whatever was wobbling.

[Lance G]

This vibration can be felt and heard. At first I felt it in my seat, now I think it is most noticable under the center hump, just behind the emergency brake handle. It happens whenever you are done accelerating, while in neutral or a gear or braking or coasting or accelerating gently.

I have now tried u-joints and tightening the motor mounts (which look new) and there is no improvement.