Norwegian activa won`t rise or fall..

HaraldG · Unread post by **HaraldG** » 17 Jan 2011, 21:41

Changed the brake doseur today.. Didn`t help

I`l do some more searching for where the "hissing" originates tomorrow..

HaraldG · Unread post by **HaraldG** » 18 Jan 2011, 17:05

Ok..

I hope you are still willing to help me make a lady again out of this french "putain"

I found most of the return flow going through the pipe in the middle of the three connected to the main-return pipe. (Near LHM tank)

Today I took of the power connector to the electrovalve on the activa-regulator at the rear.. No difference .. I can`t reach it to dismantle and check the O-ring though..

I dicovered that the "STOP" light goes if in about 20 sek when the car is started in the lowest position. And the brakes then works

I have to help the car with a jack under front left side both on the way up, and on the way down. If the front left wheel touches the ground just a little bit, the light comes on and the car won`t budge. I am also pretty sure the "normal position" on the front height corrector is way of.

I wonder if the height-correctors can be moved indepentently so that I can check if it rises in the front/back separately.

Rooling out the one with the problem? If the light comes on on both circuits I guess I can assume the problem is in the "activa-part" of the system

no

HaraldG · Unread post by **HaraldG** » 18 Jan 2011, 19:15

I`m also wondering if the antisink sphere can leak through the height corrector via a faulty antisink-valve? Do you know? It looks that way in the drawings I`ve seen.. Maybe I should check if I have any rear breaks when engine is of..

Unread post by **CitroJim** » 23 Jan 2011, 14:45

I'm still here Harald and I'm still thinking about this... Been thinking for a week now. I'll be back soon...

HaraldG · Unread post by **HaraldG** » 23 Jan 2011, 22:19

I`ve found the activa-corrector is leaking internally. I think it might be leaking High pressure back to the return side. (which it`s not supposed to do).
If it was leaking systempressure from the "activa work pressure" side, it wouldn`t cause such a big leak that the car would fail to rise, would it??

With the car standing on jack stands, I disconnected the plastic "dogbone" from the activa-corrector rod. When the car started, it pressurised immedeatly (

) and lifted the left side wheels as if in a hard left turn..

I then shut the engine off, tried connecting the dogbone back on. As I touched the corrector it hissed loudly, depressurising..

If it is stuck in the wrong position, I know it will drain from the activa work pressure (regulator side).
Is this a mater of adjustement or a faulty corrector leaking from the high pressure side...?
To find out, I plan to bleed the activa-regulator. If there is still pressure left in it tomorrow (without starting the car, pressure regulator bled, and the dogbone connected) I think the corrector needs changing.

I`ve done a lot of activa studying this week. I find it very interesting, endeed !! I think the layout of the activa system in "the citroën technical guide" is misguiding though. I mean, if you pressurised that system, both rams would extend, and not be counter acting, don`t you think?? The tekst is ok, but the drawing looks wrong...?

I`m planning to borrow a pit some day this week and either change or try to correct the corrector (

)

Deanxm · Unread post by **Deanxm** » 23 Jan 2011, 23:08

Is this corrector just a height corrector controlling roll rather than pitch? if so i would imagine the leak is the components its supplying as it tries to compensate for a right hand turn, there is nothing to go wrong with them really, its just a shuttle valve.

Of course ignor me if its some other component you speak of

.

D

HaraldG · Unread post by **HaraldG** » 24 Jan 2011, 10:13

No, it is that component

But the corrector shouldn`t feed anything when in normal position. It should close.

If the corrector and linkages are completely out of position and not calibrated, it could act as if in a sharp right turn, while the car is standing still. It would then drain from the work pressure. But would it drain so much that the car won`t rise??

If you are right, I guess it is leaking from the activa-regulator, the solenoid valve or one of the rams...

Do you have any suggestions how to check this??

My use of stethoscop earlier is not such a good idea. The sound of LHM running through the system spreads, and I can hear it in any of the components close to the source..

HaraldG · Unread post by **HaraldG** » 24 Jan 2011, 10:43

Maybe I should add that the right wheels don`t lift as in a hard right turn when the dogbone is connected...

HaraldG · Unread post by **HaraldG** » 24 Jan 2011, 14:50

Now I have bled the activa regulator.

Nothing came out when i tried bleeding with the activa-corrector connected.
When I slipped of the "dogbone" and started, it pressurised the car and I could then bleed 5,5 dl presurised LHM from the activa regulator, after stopping the car and draining the main accumulator.

I guess Deanxm is right then

.. Or else; the work-system on the regulator side actually consumes that much LHM when the corrector is simulating a hard right turn...

The car has been on jackstands during these tests. Can the antiroll bar then trap the corrector in the wrong position?

Some guidance now would really be appreciated

Unread post by **CitroJim** » 24 Jan 2011, 19:58

Harald, this is excellent progress

You're right that the roll corrector should not leak and hiss when off the normal position. The roll corrector works exactly like a height corrector except it has no damper discs in it so that it responds instantly. I have known a roll corrector leak externally but that was because it had been physically damaged. For a roll (or height) corrector to leak internally is very rare. Have you disconnected the leakage return pipe from the roll corrector to see if there is excessive leakage from it? There should be little.

The fact that the car pressurises properly when the dogbone is off suggests that you are on the right track. Even if the roll corrector is off-normal then all should happen is that one ram goes up and the other goes down with little loss of pressure and certainly no pronounced hiss.

You're right, the technical guide is not good for the layout. I have a much better Citroen diagram and will scan and post it in a while.

Firstly, there are a few other things that bear investigation in the Activa system.

Firstly, does the hiss sound like a toilet flushing? A noise that suggests a very fast rush of LHM running along pipes?

If so, it'll be worth checking the Activa Electrovalve is not leaky. Deanxm has found a broken inner O ring (see this thread) and this would allow much fluid to flow around the valve but with no external leakage. Trouble is, the valve is hard to get to, being located high in the rear subframe. It may be necessary to lower the rear subframe to get to it or else remove the whole sphere block and take it to the bench.

So, before doing that, check the ram leakage returns. Some leakage from the rams is normal but it should not be excessive. I have a front ram with a damaged piston (scored where the concertina gaiter was damaged) and big leaks can flow across the scores and damaged area of the piston. If the piston is damaged only in one place then it might be OK when say fully retracted or extended but leak terribly when in the mid-point of its travel.

If one or the other of the rams are leaking excessively there will be a big flow in their leakage return pipes.

Rams can be tested but to do so they need to be removed. If you block both pressure inlets on the ram and then pump the piston up and down it should go solid and immovable after a few strokes. Also, it should develop enough pressure (like a bicycle pump) to blow out of the inlets whatever you have used to block them. Imagine holding a finger over the end of a bicycle pump and you have the basis of the test I'm trying to describe.

If the rams are OK and the roll corrector is not leaking excessively internally then you'll have to look at the electrovalve in the sphere block. If you look at the series of diagrams I will post in a while, you'll see that if the Activa Electrovalve is leaky it can drain system pressure directly back to leakage in very short order.

We're getting there!

Give me about 15 minutes to post up the diagrams. They explain very well indeed.

Unread post by **CitroJim** » 24 Jan 2011, 20:00

Harald, forgot to say, if you open the bleed nipple on the Activa sphere block you should be absolutely showered in LHM

It should spray out at very high pressure even after the engine has been switched off for some time.

I know from painful experience. I opened it on mine and soaked me and the whole underside of my car!!!!

Deanxm · Unread post by **Deanxm** » 24 Jan 2011, 20:07

But the corrector shouldn`t feed anything when in normal position. It should close.

Indeed it should, and with the dogbone disconnected you should be able to operate the corrector manualy to get the car to lean left, then right and hold level, if the leakage happens when the corrector is closed then im stumped as it blocks any fluid admitance, the shuttle valve itself cannot be put back in back to front either so its not like someone has put it back together incorrectly, it has to be another component.

Too many Activa's are making my brain hurt

D

Unread post by **CitroJim** » 24 Jan 2011, 20:25

Dean, you are right. Look at the diagrams below and if the electrovalve is very leaky internally or one or other of the struts is leaking very badly internally then there is a clear route to the leakage returns.

Here's the diagrams:

This is the system at rest:

This is the turn in:

This is the heavy curve:

Deanxm wrote: Too many Activa's are making my brain hurt

Mine too!!!!

HaraldG · Unread post by **HaraldG** » 24 Jan 2011, 21:12

Great

I`ll check these points tomorrow.

Those drawings make a lot more sense!!

I really hope it`s not a ram though.

If it comes to it, I have the possibillity to change the entire activa-regulator for another with a working electrovalve. I can then dismantle and check it thoroughly.

It certainly sounds like a toilet flushing.. High pressure and, it seems, regardless of the rams positions..

Thanks guys !!

HaraldG · Unread post by **HaraldG** » 25 Jan 2011, 20:54

I found no obvius faults today either..

No big leaks from rams or the corrector..

I got to the return-pipe on the electrovalve return-side after a lot of fumbling. There were no leaks there..

I also dismantled the main-pressure feed pipe (The one under the bleedvalve) to the regulator to gain acces to the electrovalve.
After I was done testing for leaks in the electrovalve, I took the dogbone back of to continue testing.
When car was pressurised, and after running for a while, it popped the pipe of again, spilling LHM all over the place.. (I had been too carefull when reconnecting it

)
That suggests that it is proparly sealed too, doesn`t it?

I don`t think the regulator has anywhere else it can leak of the activa work pressure..

French Car Forum

Norwegian activa won`t rise or fall..

Problem found :)