Hydraflush and internal leaking problems

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Juliso35
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Hydraflush and internal leaking problems

Post by Juliso35 »

Hello

Nice to put a stick for the first time in this useful board. I do not speak english very well so I hope you can please understand my linguistic errors. Yes.... :oops: It would be better if I pass first through the presentations section. I'll do it!! I promise :wink:
Currently, I have problems of excess return of LHM. I have read in some parts of this forum before any maintenance to any component of the LHM is better to try with Hydraflush first. Here is known as Hidraurincage.
I would like to know your opinion first. It is true that dirt stuck in any of the components can cause internal leakage? My filters are OK and my LHM is pure green, but perhaps a debris left by an old sphere is causing this behavior. Hydraflush could help? I was told that is a very strong liquid that could cause further damage!

My car is a 2.0 Turbo CT HA State with which I am pleased but certainly the problem of excess LHM return is driving me crazy.

Some observations:

Tick ​​rate rises in the morning as the engine warms up. Currently down 12 to 5 seconds.
Main accumulator 50 BAR but temporarily exchanged with the Hydractive Sphere and still remained the same
I did the Regulator test using a gauge regulator only connected to the output and it marked 168 bar. The residual pressure (before 140 bar) was maintained 8 minutes after stopping the engine. According what I read in the service's manual if more than 4 minutes, the regulator is OK :wink:
There are no air bubbles in the tank. 8-)
A strange thing is that when I do any test in the morning and the car parked with the engine at idle I can get tick rates up to 50 seconds. But once I go riding time decreases quickly!!
The electrovalves make the characteristic buzzing sound ​​and cut-out in the time expected. I did the test to force the hard state by disconnecting one of the EVs - in this case was the front electrovalve- in the morning and the tick rate increased but after a while so move back to the time 5 seconds. :cry:
I also read somewhere on this forum about making a test by lowering the suspension and see if there are changes in tick rate. In this way, I think, you know if there are problems with any strut or with height correctors. There wasn't a very noticeable change. :(

Anyway this weekend I'll check the returns and see the flow amount on each one when the engine be hot the I'll comment the results!!

That's all for now! Thanks in advance! :) :mrgreen:
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Re: Hydraflush and internal leaking problems

Post by Peter.N. »

Flushing the system might improve it but there is no guarantee. The reason that time interval is greater when you start is probably that because the engine is cold the fluid it thicker. Providing that the accumulator sphere is good I wouldn't worry about the ticking speed providing everything works allright, one of my XMs ticks about every 10 seconds and has been doing it for years. You could have leakage practically anywhere and it could cost you a fortune to cure it. You can find out where the leakage is occuring by removing the return pipes from the LHM tank one at a time, you should find an indication of which pipe is connected to what somewhere on the forum.

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Re: Hydraflush and internal leaking problems

Post by Juliso35 »

Opsss No replies??? :( :( :( :cry:

I know this is a very often treated topic. Indeed the supesticky post has a very useful link there but it doesn't mention of the relationship between internal leaks and the possibility to solve using Hydraflush. Maybe someone has had an experience like this to share :) :)

Ok guys.. anyway I find this board very interesting. Thanks for all ;) Thanks Steve for the access!!



Regards
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Re: Hydraflush and internal leaking problems

Post by Juliso35 »

Thank you Peter. Your response entered at the same time with mine. :lol:

Bad news then!! :(

There should be a kind of thicker LHM. A kind of "LHM +" for hydraulic systems with aging as with engine oils :? :? . There any way of thickening "at home"??

I'll check the returns and I'll shot a video to share with you!!

Thanks again
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Re: Hydraflush and internal leaking problems

Post by Xaccers »

No, and thicker fluid would put extra strain on the system and not work the same through the spheres i would imagine.
Either put up with it or replace the faulty part by finding out what is leaking internally.
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Re: Hydraflush and internal leaking problems

Post by CitroJim »

Welcome Juleso :-D Your English is very good :-D

I must say you have done all the tests to try and isolate this problem. However, I am not happy with how you have forced hard mode. That is not the best way.

Normally, fast tick rates on any hydractive car is down to electrovalve leakage and the best way to force hard mode for testing is to power down the Hydractive ECU by removing F8 in the engine bay fuse box. If yours is a very late Activa (Year 1999 -2000) then the fuse to remove will be F3 in the passenger compartment fuse box. You will know which it is as you will hear the electrovalves stop humming when the fuse is removed. This will force a permanent hard mode.

Recheck the tick rate. If it is now good them you have the problem. If not try with the suspension set high, normal and low. Any difference in tick rate?

This will determine if strut cylinder wear is the cause. It rarely is.

Switch off the ignition before replacing the hydractive ECU fuse. If the tick rate is good when hard mode is forced then you definitely have a leaky electrovalve but which of the three is it?

Start the car and allow ride height and hydraulic pressure to become normal. then switch off. Close all doors and bounce the front up and down for at least 30 seconds. It should be soft initially and then go hard once the electrovalve switches off. If it goes hard before the 30 seconds have elapsed then the front is the leaky valve. If that test is good, repeat for the rear. On both ends you should be able to feel the suspension soft and then switch hard after 30 seconds. If all is good, on opening a door to put the suspension in soft mode again, both ends should go soft again even with no engine running.

The Activa electrovalve may be leaky but there is no test for this except by disconnecting its leakage return pipe and observing how much LHM runs from it. Access is hard and I hope by now you have found the problem!

The other rare cause of the problem may be the brake dosuer valve but I don't think so as your pressure gauge tends to suggest that the system is pretty much leak free.

Please let us know the result of these tests...
Jim

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Re: Hydraflush and internal leaking problems

Post by Juliso35 »

Hi Jim ... Thank you for your answer. At last we can talk on here! :o Finally those zip files were useful?? I have one more about a drain on spacer of doseur valve to avoid flooding the carpet with LHM :wink: :-D

Ok .. Really my car is a Hydractive 1997. I will check the fuse as you say F8 or F3. How many amps is that fuse?

Today I was doing more tests. :| I checked the front electrovalve return flow. Was something significant. Then I dismounted it in order to stretch a bit the famous spring. By the way,... :oops: I have to say that I forgot to depressurize the system first. Can you imagine the mess of LHM under the car?. :oops: :lol: :lol:

Well,.... after I reinstalled the electrovalve again the same strange behavior :? tick rates of 50 seconds, but as usual, once I go out to ride, tick rate down again to 5 seconds. Also I checked the returns of height correctors in the tube No 2. (I previously did this octopus changes that allow me to see each tube separately)
I must say that they had some leaks. One drop every 0.8 seconds maybe :oops: Meanwhile the flow of the tube No. 6 that also brings another kind of flow from height correctors, is nearly zero.
Here is where I have my suspicions about these height correctors too. So my question about the use of hydraflush :wink:

Ok... I'll try to force the hard state as you suggest me and the other tests. I'll be back with the results!!

Regards
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Re: Hydraflush and internal leaking problems

Post by Juliso35 »

Hi All!!!

CitroJim,.. Thank you for your support. Well,... I performed the tests that you suggested me. I set the suspension at all heights but there was no notable change in the tick rate. :? Also,. I made the test of bouncing each corner of the car with the doors closed. Indeed, in the front I noticed that the hard state quickly came long before the EV's were inactivated. Then I removed and opened it again. I think this stretch of the spring degrades over time because after a day of riding in the car again had this f***g leak. :grr: What do you think? :-k

It is possible to change the type of spring for a harder or necessarily have to change the full EV?

It's pretty hard to explain things in a different language than yours. Finding the right words is difficult :oops:
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Re: Hydraflush and internal leaking problems

Post by citronut »

to repair the in cabin hydraulic leak you require these two parts below

Part Number Description Quantity Price excl. VAT Price incl. VAT Total incl. VAT Selection
5424455 CNTRL-UNIT RING 4.82 GBP 5.78 GBP 5.78 GBP

95640067 BRAKE PROTECTOR 7.99 GBP 9.59 GBP 9.59 GBP


regards malcolm
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Re: Hydraflush and internal leaking problems

Post by KevMayer »

Hello Juliso35,

Which of the electrovalve springs did you stretch? Was it the small spring or the large spring?
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Re: Hydraflush and internal leaking problems

Post by CitroJim »

Juliso,

No problems on the language, we understand you absolutely perfectly :-D :lol: 8-)

Did you do the test on the back and was this OK? did hard mode coincide with the electrovalve (EV) switching?

From the tests you have done, it would seem the front electrovalve is leaking badly. I've known a spring stretch (it should be the small spring) cause the problem to get worse and usually this is because the very end of the spring is out of place and interferes with the needle seating properly. You can often hear this problem with your ear. A very leaky electrovalve will sound like a toilet flushing as you turn the engine off. The noise is made by LHM rushing up the leakage return pile. It can be confirmed by removing the leakage return pipe from the top of the valve and plugging its end. Then run a lenght of clear plastic pipe from the top of the electrovalve into a large jar. leakage in both hard and soft modes should be minimal and you should only see a spurt of leakage as the valves switches from hard to soft.

Hope that translates OK...
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Re: Hydraflush and internal leaking problems

Post by Juliso35 »

Hi Kevmayer

The spring I stretched by a 30% was the smallest and weaker. I was told elsewhere that perhaps could be changed by another stronger :?

Citronut. Thank you. I have those parts already. :wink: As you see, we are trying to make and detect an internal leak which can be between the doseur valve and the electrovalves.


Citrojim to the rescue.. \:D/ It is comforting to know that I do understand to others!!

I did exactly what you said and everything was perfect after stretching the spring, but after a day of running, it seems that the spring has lost this stretch. About the needle seating I know well because on another occasion I 've tried another spring and the sound of the EV when disconnects is softer (muted) than usual. The soft mode was always set. I'll try another harder spring. Is there any last minute recommendation?

Regards

P.D. Now,... I know where the "castle gate" sound comes from. Is the sound of a leaky EV :wink:
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Re: Hydraflush and internal leaking problems

Post by KevMayer »

This picture shows the electrovalve laid out.

Image

Is the 'O' ring ok on the inlet (seen bottom right in the picture)?
Cheers, Kev

02 plate C5 2.2 Hdi Exclusive SE (now 170k miles 03/21).

Used to have:- Xantia 1.9 TurboD SX. 1996 Blue & 1998 Silver Activa. + 1992 BX TZD Turbo.
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Re: Hydraflush and internal leaking problems

Post by Juliso35 »

Hi Kev

Of course. I understand if this o'ring is defective, it will leak on hard state also right?

Thanks. Tomorrow I will buy "many" springs of this size and do more tests.
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Re: Hydraflush and internal leaking problems

Post by Northern_Mike »

Juliso35 wrote:Hello

Nice to put a stick for the first time in this useful board. I do not speak english very well so I hope you can please understand my linguistic errors:
Hi Juliso,

I can't offer any help on the tech problem you are having - CitroJim and the others are better for that, but if you have any trouble with the language barrier - you appear to be in Bogota - my wife is Colombian - so post in Spanish, and I'll get her to translate it and repost for you :-)

Also - I often know of people flying from the UK to Bogota... so if you need parts that are hard to find, maybe we can arrange to get them to you!
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