Suspension querry

[Martyn-123]

Hi,


Just about to put my Marcos on the road after a 3 year restoration and just wondered about the suspension settings.

The car has koni 8212 aluminium shocks front and rear which i understand are quite special units. I will be having them rebuilt shortly by a Koni authorised dealer but just need to get the car MOT'd first and was not sure about the settings, the front of the car is sitting a little low and have adjustments on the actual shock absorbers and can also alter the preload on the spring itself. I did tighten the collar on the spring which raised the car height but over a couple of days (car resting) the front of the car lost height again and when i lift the bonnet the front edge touches the floor telling me its too low.

Is there any guidance as to how tight/loose the collar should be on the springs, any advise gratefully recieved as on a learning curve, i will get the car set up properly once on the road,


Regards,


Martyn

Edited by Martyn-123 on Monday 19th December 06:43

[DanGPR]

There should be two collars that rotate on the bottom of the struts, one that the spring sits on and the other is to lock against the other to stop it from spinning.

Are you sure that what you adjusted wasn't damping? There's no real way of the spring perches winding themselves down whilst the car is just sitting in the garage.

[Martyn-123]

Hi,

Thanks for reply, no the collar has not moved.

There is plenty of info on the www re setting the rebound and compression settings on the shock absorber itself but can't find any guidance at all re setting the collar on the spring,



Martyn....

[one eyed mick]

the springs control ride hgt not the dampers ! so i dont quite see how the car can be setteling lower after adjusment ! unless you adjusted the spring collars the wrong way ?more inf please

[Sam_68]

If the dampers are fairly stiff, it's possible that they were helping the springs to hold the front up when you adjusted the spring perches (I assume that you took the wheels off to do this... obviously this allows the suspension to go to full droop, and the stiffness of the dampers might have resisted it settling back to 'ride' height when you dropped the car back onto its wheels). If the dampers have just been rebuilt, some of the seals may be a bit 'tight', which would exacerbate this problem.

Re-set the ride heights (or corner weights, if you can get hold of the becessary scales) by screwing the spring seats up and down (tip: work on diagonally opposite corner), but this time make sure you 'bounce' the suspension when the car is dropped back onto its wheels, to ensure that the dampers have settled back to their proper 'ride' position.

[Martyn-123]

The dampers are due for rebuilding but need to get the car up and running first.

I have tightened the springs up each side with the front of the car raised. It has raised the height of the car which is what i want but wondering having the springs tighter does this affect the settings ?

Will monitor now to see if the front end looses height again overnight whilst resting,



Martyn....

[Sam_68]

Martyn-123 said:

It has raised the height of the car which is what i want but wondering having the springs tighter does this affect the settings?

It affects the corner weights, certainly, so you should look upon it as a temporary measure until you get the corner weights checked, if you want to do it properly. Having said that, if the ride heights at all 4 corners are correct, you shouldn't be so far out that it actually makes the handling dangerous or anything.

The only other potential problem is if you have had to screw the springs up so far to get the correct ride height, that they have a lot of preload as a result (ie. with the damper at full extension, the spring is still heavily compressed between the upper and lower (adjustable) spring seats), which wouldn't be ideal.

Edited by Sam_68 on Tuesday 20th December 19:21

[Martyn-123]

Thanks for replies, as i said only a temporary measure to get car on road through MOT, will then send off dampers to be rebuilt and then get car set up properly


Martyn?..