Suspension clunking after changing coilovers driving me mad!

[jonamacg83]

Hi all, I have fitted a Nitron Kit NTR one way to my Lotus Exige, and followed correct procedure, everything has been tightened to the correct torque levels as specified in the Lotus manual, I even cleaned up the threads with a wire brush to ensure they are torqued up correctly. All the relevant spacers are fitted and yet the suspension 'clunks' over each small pothole/manhole cover etc that I go over. What is more bizarre is that each corner does it, so its obviously something to do with the units themselves or indeed the way they are fitted/setup. I have fitted coilovers to cars before and never come across anything like this. The rideheight and damping is adjustable, the current damping is set to factory settings and I have messed about with the rideheight but it is in the right ballpark.

Someone suggested that it could well be that I have overtightened the joints at the top and bottom (I did do them up pretty tight after I initially fitted them with the correct 45Nm) of the coilovers and hence seizing the bushes/ball joints. I struggled away in the dark tonight after work and slackened them off and there is no improvement what so ever.

If anyone has any ideas they would be greatly appreciated. Its driving me nuts! I have tried all the Lotus forums I am a member of but to no avail.

Thanks in advance.

[MiniDiva]

We had this on our S1 elise after fitting Protech shocks, a friend had mounted his the other way up to us and had no problems. We turned them around and that cured the problem. Seemed very weird but worked a treat.

[Scuffers]

you need to describe the 'clunk' better? (one man's clunk is another man's thud etc)

also some pics of the install might help, specifically the joints top and bottom.

dampers themselves do make some noise, Nitrons are not immune from this, but their normal Elise range it's not noticeable.

[jonamacg83]

The 'clunk' is a very solid, similar sound to the one you get with a worn steering rack or when a caliper is loose etc. What really puzzles me is the fact that it occurs on all 4 corners. I will get some pictures up asap.

[Wildfire]

If it's all four corners, then it woudl suggest that they may have been supplied with the wrong bushes??

[Scuffers]

Wildfire said:

If it's all four corners, then it woudl suggest that they may have been supplied with the wrong bushes??

NTR's don't have bushes....

[danwebster]

Are they second hand?

My best attempt at an internet diagnosis suggests that you either haven't done them up tight enough or the rod ends are shagged.

[jonamacg83]

They are brand new, so I doubt its the rod ends. I tightened them up to 45Nm as stated in the Lotus manual, maybe that simply is not tight enough?

[danwebster]

Quite possibly - presumably this is the lotus manual referring to rubber bushed dampers?

I'd just do them up until my eyes almost pop out to be honest, forget the torque wrench.

[danwebster]

45nm is about 30ft lb isn't it? I do my valve caps up tighter than that

[s.m.h.]

Ok, not a Lotus man myself but.... Is there any preload in the spring or is it loose on full droop?
Might be that you need helper springs if the spring seat is allowed to move over bumps. Noise you hear might be the spring moving on the platform?
Pics would help!

[Scuffers]

45Nm is the right number.

something more to this that we have not seen yet.

[jonamacg83]

Not much conflicting advice on the torque settings then! Definitely some preload on all the springs at full droop. Will get photos up as soon as, though its fairly snowy at the mo and don't fancy battling against the elements!

[TIPPER]

When I fitted my Nitrons all sorts of previously unheard bang, thumps and clunks became apparant. They all dissappeared once I renewed all the articulating parts of the suspension - the car now rides as near silently as an Elise will ever (I suppose).
That was on a 70k mile S1 though so everything was past its best although maybe if your car has had a lot of track use and spent time riding kerbs then it might be time for simiiar?
Not much help really, but improving my dampers and fitting stiffer springs just showed up tiredness in the rest of my supension.

Just as an aside, as you originally tightened the bolts to over 45nm then you may have overstretched them so they might be worth replacing? I'm sure Scuffers or someone else more knowledgable will confirm or otherwise.

[jonamacg83]

My car is on 45k miles, so it could well be the case that it needs a hefty refresh, though I am surprised that I wouldn't have heard all the noises previously.

I can't imagine I have managed to stretch the bolts, as I was only using a 3/8 ratchet spanner to do them up.

[polus]

Have you had a pry around the various joints to see if anything has excess play in it?

[TIPPER]

polus said:

Have you had a pry around the various joints to see if anything has excess play in it?

Apart from my steering rack needing a refresh everything on my car felt fine - the difference after a refresh was night and day though. Certainly not a subtle difference. It would have passed through an MOT with no problems (apart from the rack) but after doing the job is was abvious everything was waaaay past its best.

[jonamacg83]

I have had a brief check - Pushed things around a bit with a pry bar to find some play but nothing is apparent. What baffles me is its the same noise on all four wheels, which was not there before, I can't see how the old shocks would have covered up the bangs previously.

[Ruxpin]

Might be completely unrelated to your issue - i can't see if yours are loud when stationary

On my S1 after replacing the rattly konis with a set of S2 dampers i was expecting a silent ride but was baffled by a rattling/knocking sound.

Turned out to be the rs42 pads rattling in the front callipers! I'm still amazed at the amount noise they made. When fitted they had the anti-rattle buffers in place but had fallen out over time.

Driving along and just dragging the brakes fractionally would make the car silent - took me a while to work out though....d'oh

[Martinsalharris]

Hi, did you solve this issue as I appear to have the exact same thing on my Elise after fitting Nitron NTRs