Hydractive And Estates, continued from HID thread

[steelcityuk]

You could well be right George but to be honest I'm not too bothered about spending even more time on a car I'm indifferent about but thanks for the offer it's very kind of you!

I had problems on the Xantia Exclusive I owned, despite countless hours it never was that comfy. The 2.5 is much better than that was.

>>Hmmm I can see Noz being very angry for me posting again to the wrong section! Sorry Noz, we'll continue where we should.
G

[jorgy9]

Yeah, I remember your interesting Xantia investigations with the leaky electrovalve etc...

I see you r decided for the fate of the 2.5, let's hope your next one will be alright, if not, we are here to get it right!

cheers
G

[jorgy9]

Just thought it would be useful to repost the original post re. if estates are harder than ahtches, for future searches:


Hi Steve

No, I've driven only mine, and it's my first hydropeumatic car also. I've seen it go through different phases/combinations since I got it (2004 +25,000miles): wrong spheres, shot spheres, diodes burst, wrong height, hydraulics dirty, hydraulics after 1,500mls hydraflush (no difference), hydraulics after 2nd time 5,000mls flush, middle spheres not opening, finally pressure regulator tuned and middle spheres opening the next moment for first time in my ownership. Car became perfect for that one day in March 2006, till the next day when I bled the brakes and on the process something happened and it went back to "not-so-soft". It's getting back to normality now, as you are reading elsewhere. I'm glad I saw it for one day operating as it should, because one cannot understand, just cannot imagine how good it can be unless he has driven one -no matter what you've read about "magic carpets" etc-. Today, I find no logical explanation other than lots of dirt having moved in the system during these 2 hours I had it on "highest" with engine running (to bleed brakes), and having blocked the hydractive blocks (symptoms [sideways rocking as if I had a very stiff antirol bar] show it mainly blocked the cross flow between corners, if not the 3rd sphere opening) and also went to the suspension cylinders and made them stick, but now it is slowly all washing away. I have had evidence for both issues mentioned. Plus, there's nothing else that changed since March 2006, all else remains same: regulator cycling time, spheres (had re-measured for pressure in 2007), etc. It was only the dirt.

To the point: I've read around that estates are not so soft as hatches; this reminds me the other thing that goes around, that V6s are not so soft as 2lt "because they are heavier". People go and think of all kinds of fallacies to conclude that a heavier car will be less comfortable than a lighter one. The other story that also goes around is that "hydractives are not as comfortable as traditional hydropneumatic Citroens" -I've read this in both UK and French forums, mostly non-interested garages reproduce this story and then clients go and spread it around-. Jesus Christ, all the theory shows that hydractives should be *at least* as comfortable, if not more! You see the point Steve. Estates have larger volume middle spheres at the rear, this is only beneficial for comfort. From below: the estate's corners (+10bars) is the only differrence, these will give a softer springing on compression to an UNLADEN estate when car is in "hard" (weight difference: +6%, pressure diff: 33%). When in "soft", the extra 100cc in the middle would make for looots of softness (the estate would take greater height bumps with same softness a hatch would take smaller bumps).

.................corner .......... middle
hatch ... 400cm 30bar ... 400cm 50bar

estate ...400cm 40bar ... 500cm 40bar


Do estates have firmer damping? For corners, I don't know. For middle spheres, answer is No, there's only one code for the hydractive blocks, for all models, so they should all have the same damper tablets inside (about 1.2mm orifice).

Do they have thicker antiroll bars? Yes, the front is 25mm, when the V6+2CT+2.1 have a 24mm and the 2lt 23mm. Is my V6 feeling not good because of the 24mm instead of a 23mm on a 2lt? No, actually I don't see how it could feel better...It's heavier so this just compensates for the stiffer antirol. The rear: all 21mm, V6 24v 22mm, estate 22.5mm. Same comment.

Steve, I don't think you should see a stressed difference with a hatch, comfortwise. The only things I can think of that you've not done are:

1/check pressure regulator for correct pressure output
2/check e-valves for leacking (my front leaked)
3/extensive hydradflushing.

I wish I could post you the pressure gauge my indy has for you to test it. I think he'd hapilly borrow it to me -he's done in past-. Do you think we could organise it?

cheers
George