Drilling Out Sphere Damping Holes!

That also explains why you cant depressurise the centre sphere unless you've got dodgy diodes.

Uhh, this meant as a humorous observation? If not, of course there is a procedure to depressurise the centre spheres I have seen it described in the books and used it myself

If all the connections are rusty, its probably just as easy to pour LHM all over you

Hi Dean

just chekin'

1. So you do notice the difference between soft/hard when you push your car yourself, playing with the suspension ecu fuse (not the "sports" switch)? Is the car in "soft" as compliant as the 2 XMs shown in the videos at my signature, or not really? In my car, pre-flushing, there *was* a difference but it was small (1cm at "firm", 2-3cms at "soft").

2. Have you looked under the car, engine running, at the electrovalve return, to see if it's leaking? (mine was seeping with car stationary, so I can imagine it would well close when receiving the back-presure from hitting a bump).

3. Afair, your regulator clicking time is pretty good, near 1 minute?

cheers
G

This post has been edited by jorgy9 on July 22, 2008 11:16 pm

Hi George

1. Yes i can tell the difference between sports and auto, since i drilled the sphere's it has become more of a difference between the two but i haven't tried removing the hydractive fuse,

2,The electrovalve does need checking, if i leave the car for a couple of hours then come back it is still at normal ride height but when i open the door and the electrovalve energises the front will drop slightly? and since i now have a brand new h/c and a good pressure regulator plus the struts dont leak a drip i can only assume that premature closing of the slide valve in the hydractive block would be due to a worn/faulty/leaky in some way electrovalve but it seems to be working fine ie opening and closing when its told to. will check for leakage this weekend though.

3,Strangly it was 45sec's a few months ago but i checked it yesterday and the regulator seems to cycle at 37-38sec's despite now having a new H/C, maybe due to the acc sphere loosing a little pressure since it is now 17mnths old but i dont know.

Regards

D

Ok, so:

1. Alright, there's a difference. The second part is equally important: how great is the difference?? If you are unsure it is very great, then 99% it means it's not right. Look at the 3 vids in my sig/re. Is your car giving in *as much* when in soft? The front should move freely about 5-10cms when pushed from the front, and the rear should bottom out easily when you seat on it -about 10cm+ of movement-. [Can we keep our reference to the standard spheres, all 3 vids are on standard spheres not comfort].

2. The front drops as the middle sphere opens, and as it is at a lower pressure than the suspension, LHM from the corners rushes into the middle sphere. This is not good:

When you shut off the car and the e-valve shuts off, the middle spheres close and stay at the pressure they were at that moment. So pressure in corner and middle spheres is equal. You come back 2 hours later and the remaining system pressure is able to open the middle sphere. This is not a good sign initially, as in principle -unless the hydraulics were totally watertight which they are not- the system pressure 2 hours after will be considerably lower than when u left the car. Still it manages to open the middle sphere.

Second, the car drops, i.e. the pressure in the middle sphere is lower than the suspension's pressure. If this sphere had ever opened up properly, remained open all the way to "riding" pressure, where has this pressure gone?

This pressure can only escape through the hydractive piston, in 2 directions:
a. towards the other spheres (not your case obviously as your pressure is not being equalised), b. towards the electrovalve (i.e. this one is leaking in "closed" ["sport"] position). The other, 3rd possibility, is that due to inadequate pressure the middle sphere has never opened up properly and so it remains in some very low pressure, so low that your remaining system pressure can open it up 2 hours after. Then your car drops, height corrector comes in, the front builds up pressure and rises, and at some point on the way, the front piston cannot stand the pressure and closes again, having stored some pressure which is below the "riding" pressure of your front suspension. You drive all day without your middle sphere, come back, shut off, and it all repeats. The rear could still be opening up properly as it's lighter than the front.

3. Ok so your system seems to hold pressure well. This, in combination with 2., potentially points out low pressure as the suspect.

4. Can you also try this for me please: enter car, put in "lowest", start up, put in "highest". As the car rises, listen carefully for the pressure regulator. How many times exactly does it click till car reaches maximum height? Do the test: a. from cold, and b. with car having run some miles at least.

5. What about the FDV valve?

Please let me know of 1. and 4., and of 2. the e-valve return.

cheers
G

Ok George will do it this weekend and post the findings on Monday.

Many thanks
Dean

Hi,

I found it worked quite well drilling out the centre hole. Using a rare earth magnet on a slow speed cordless drill with the sphere upside down should be as safe as possible. The amount of swarf is minimal due to the small difference in hole size.

Another side effect of this is the increased strut travel which moves more fluid which is a good thing if you're running Hydraflush in your system. The spheres are only about £22 pounds each from GSF so if you're careful what have you lost? It's not a permanent/unreversible change.

Steve.

Hi Steve,

I really done it to protect the strut tops from the harshness while i sort the cause of the problem...........which has now stalled again due to my holiday.......but on the plus side it will give the flush a chance to do its thing, and like you say its only £40 to replace them once its all back to normal.........fingers crossed .

D