A recent experience with Dampers ....

[ECR]

Shock absorbers/dampers

I thought I’d share some recent experience with you concerning those things inside coil springs on each corner of the car. I’ve been chasing chassis noise on my Elise (but the same will apply to a Seven) for some time. The car rode well enough on reasonable surfaces but put it on the rough D roads of the commune and it progressed over each pothole with a series of sharp CRACKS from the chassis, this although there were no noticeable problems with the handling.

It sounded for all the world like worn suspension bushes/links so I did all the normal things. I replaced anti roll bar drop links (which were worn), then the upper and lower upright bearings. I found a slight play in the track rod ends but as the car needed to be presented for its controle technique (MOT) I left them as they were. It sailed through the test and the tester gave me the certificate. Just before he lowered the ramp I had a look under the car. The nearside damper was significantly dirtier than the offside and a closer look revealed that it was dirt sticking to a thin layer of oil which was obviously leaking from the damper.

I replaced both dampers and took the car out for a test. No difference in the road handling but the big surprise for me was that the CRACK that I had been chasing had disappeared. I never thought that a substandard damper could cause so much noise (whilst still being roadworthy).

Lesson learned, they obviously do “Damp” out the “Shocks”

[Drumster]

Thanks for that Roger as it gives me a degree of comfort as I've recently experienced the same phenomenon. I, too, could feel the crack through the chassis on local roads but it has been fine on recent sprints.

I'll mention this to the manufacturers as they are looking at the damper for me as the adjustment knob turns far too easily and it may all be related. I don't have any noticeable oil leaks but maybe there is a loss of gas pressure.....

[Johnh]

I'm a little surprised the MOT guy didn't pick that up ...reporting on leaks to shocks is as far as I know is part of an MOT.

 

[7 wonders of the world]

Control Technique centres focus on performance using a shaker plate which takes the dampers through a predetermined cycle of varying frequencies and records accordingly.