Rear Rattles and non symmetry in dampers

[TomB]

I spent part of the afternoon looking for the causes of rattles from the rear near side suspension of my 1997 De dion. I have not been able to find any loose nuts & bolts.

 

The spring on the near side of the car could be rotated around the axis of the damper & upon shaking seemed to make the correct rattle.

 

There was about 2 cm of thread exposed at the top of the damper. The offside damper had about 4 cm of exposed thread and the spring was tight. I assume they should both be tight.

 

To correct this is it just a case of buying the spring adjusting tool and screwing it to compress the spring? I dont want to fiddle with the suspension settings cos I know nowt about it and I dont want to adversely affect the set up.

 

Are the screw adjustments meant to be equal or are they a method of correcting the spring / damper setting as the dampers wear and age?

 

I also noticed the 4 settings for the rear roll bar - mine is on the rear most setting. Is this the best for road use? Is this the setting for least or most roll?

 

Someone please explain the spring / damper relationship to me and the effects of adjusting the suspension adjustments at the rear.

[Mark H]

It sounds like you rear dampers/spings have been set up to take account of driver wieght , and there for will not be equal in platfom hieght.

The most common cause of your rattle does sound like the spring rubbing on the damper body(quite common im affraid)

 

How do you find the handling/balance of your 7 ?

 

Do you lock one corner under hard braking?

 

 

Marc.

 

 

Edited by - Marc Hicks on 15 Sep 2002 19:57:18

[scooby dooby doo]

before doing anything else you should investigate with your weight in the car. put compost bags, spuds etc in the drivers seat equivalent to you weight - then bounce the car a few times to settle things and have another look.

 

Its still not ideal that the spring can become loose like that bt it may not be as bad as it seems...

 

HOOPY R706KGU CYCLE WINGS AEROSCREEN K SERIES CUCUMBER

[Peter Carmichael]

Sounds like the car has been flat floored which is a good thing.

 

If the spring is *just* loose then leave it as it is. If the car understeers, then you might jack it up by a couple of turns on both sides. If the car oversteers or feels unstable then you might jack it down by a couple of turns on both sides.

 

This is nothing to do with spring/damper wear, but is fine adjustment of how the car sits on its springs, coping with the uneven weight distribution of the offset driving position and the assymmetry of placement of the exhaust, battery and other components.

[TomB]

Thanks for your input chaps.

 

The car handles and feels fine. The chap at caterham mentioned a good point: if the car is jacked up on axle stands with both wheels off, the springs & dampers will be at their max extension, so the spring may well move a bit.

 

I wondered if a previous owner had had it flat floored as apparently they used for exclusivly track days.

 

This weeks job is too replace the alternator & refit the exhaust manifolds! No rest for the wicked 7 owner!!