hydra flush

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goodier
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hydra flush

Post by goodier »

do you drain the whole system on the car then put the hyra flush in is draining the system a straight-forward job,
do i have to bleed the brakes or the system, ok with the spanners but this is a new field to me.
tony42
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Post by tony42 »

see post re citroen suspension overhaul it has links to instructions re completing this task and also contains useful advice from the experts on the forum. Did it myself today. Its not too bad. I was a bit slow as it was my first time attempting this. Usual got my mechanic to do it
rgds Tony
BonceChops
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Post by BonceChops »

It is definately worth doing.
My car has 149k miles on the clock and I replaced the LHM with hydraflush on Sunday. The red lights go out faster in the morning and the car drops less and raises faster. The brakes feel smoother, especially when slowing from high speed to stop fast ( motorway slip road to roundabout [}:)] ), ride feels smoother as well.
I bled all the brakes as well.
I am not sure it the improvements are due to the new fluid, clean filters or both. I suspect the filters made a big difference but, I think the LHM was very old as it was a dirty green colour.
All in all probably the best £13.50 + VAT I have spent in a long time. Now what do I do with the remaining litre of hydraflush I have left.
kosio
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Post by kosio »

I just went out on Saturday and bought a 5L Hydraurincage and a 1L of LHM (just in case).
Drove to a quiet place, lowered the suspension to min, couldn't find a depressurizing knob/screw/etc so didn't do that, ran the engine for a while then turned it off.
Removed all the pipes leading to the LHM reservoir, removed the bracket holding the filters/cap (took me a while until I figured it out ;-)), unscrewed the 2 nuts holding the reservoir to the body, drained as much old LHM from it with a pipe and removed it.
Cleaned the filters (quite dirty; especially the one filtering the LHM to the pump), cleaned the reservoir as much as I could reach through the tiny opening on top... BTW, if anyone knows how to open the container it would do me a favour...
Reassembled the whole thing and poured aprox. 4L of Hydraurincage (I guess about a litre of the old stuff stayed in the system :-( ). Did the citaerobics (3-4 cycles) and hard-left hard-right with the wheel (3-4 times).
Checked level (suspenssion high) - topped and was done.
Took me about 2-3 hours for a first timer - not too hard really.
Performance now is noticably different - healthier is the best description I guess - rises faster, stays up longer.
It's a Xantia 1.8i march.1994 with 120k km on the clock, BTW.
HTH,
kosio
Ah, forgot.
Old LHM had a orange-brown dirty-looking colour.
Probably hasn't been changed ever...
-k
BonceChops
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Post by BonceChops »

The pressure release screw is a 12mm (might be 13 but sure it is 12mm) hex head bolt to the right of the accumulator sphere just behind the radiator. You cant miss it as there is only one. When you refill with LHM in 2000km or so it would be better if you can de-pressurise the system first.
kosio
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Post by kosio »

Do I understand correctly that by depressurising the system I can get more of the LHM out of it?
kosio
tomsheppard
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Post by tomsheppard »

Yes! the accumulator holds about half a litre. The pump also primes up more easily with the bleed screw open. More experienced owners/wrenches than myself reckon that if you change the LHM annually and rinse 4 yearly then the hydraulics last for ever with just a change of spheres every 30,000 miles being the only work you'll ever need to do.
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Kowalski
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Post by Kowalski »

Depressurising the system will make the spheres empty themselves of LHM. Lowering the car will make the suspension cylinders empty themselves too.
The pressure release screw is a 12mm. I accidentally undid mine with a 13mm socket when I changed my LHM last, I couldn't see it properly so couldnt really tell but it felt "wrong", so I checked with a 12mm socket, that fitted and I used it to tighten it up again.
kosio
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Post by kosio »

Aha.
I'll do filter cleaning on 500km marks and will top up with the remaining hydraflush.
But when I change it with LHM I'll definitely try to depressurise the system then.
I'll fit in the new spheres then when the system is all clean too.
Now I'm running on 5 regassed @ 119k km which I did a couple of weeks ago. They where almost
completely flat - 9-12 bar each (probably never changed before), as one of them had sucked
some of the LHM inside the gas chamber - seems to be holding for now though.
kosio
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