hydraflush ?

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froggy
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hydraflush ?

Post by froggy »

Hi what"s the benefit of hydraflush ? I"ve never done it .
cheers Terry

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Xaccers
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Post by Xaccers »

Cleans gunk from the hydraulics system, definitely worth doing.
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Post by Stekelly »

Sorry for hijacking but could groanign from the front on switch off be caused by (or more to the point fixed by a flush?) never having seen a flush? My car was laid up for the best part of 2 years up till 2 weeks ago. After a few days use it now groans when turned off.
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Post by Xaccers »

It's the anti-sink valve not closing properly/quickly enough, and the groaning is it vibrating as LHM leaks past, causing the front to sink.

Low pressure in the spheres can cause the A/S to be slow, or gunk in the way of the shuttle valve inside, which hydroflush will help with.

The antisink valve is kept open by the pressure supplied by the pump, and closed by the pressure supplied by the corner spheres when the pump pressure drops.
If the spheres are nearly flat then they can't push hard enough against the valve and it doesn't close.
1.9TD+ SX Xantia Estate (Cassy) running on 100% veg
1.9TD SX Xantia Hatchback (Jenny) running on 100% veg for sale
Laguna II 2.0dCi Privilege (Monty)

DIY sphere tool
Stekelly
Posts: 257
Joined: 17 Mar 2008, 01:21
Location: Dublin, Ireland
My Cars: 2022 Trafic work van
2017 Kadjar

Previous
06 C5 1.6 HDI
00 Xantia 1.8
00 Clio 1.2
98 Xantia Activa (briefly)
97 Partner van
97 Safrane 2.5 Auto
94 Safrane 2.0

Post by Stekelly »

I changed al the spheres, bar the front accumulator because I couldnt get it off at the time, shortly after I got it. I assume the car sittign up for 2 years could have killed the spheres yeah? would the accumulator that was new ut has sat in the boot all that time still be good?

cheers for the help Xac
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Xaccers
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Post by Xaccers »

Spheres off the car should last years and years as the membrane inside is pushed tight up against the inner wall of the sphere.

Sphers on the car, except when on low (if they have enough pressure to empty themselves), are able to lose gas through the membrane into the LHM over time.
If they were genuine new Citroen spheres then they should last more than 2 years without ill effects.
3rd party sphers like amtex which are decent and a fraction of the Citroen price would probably be down on pressure after 2 years.

What's your tick rate? Engine idling, listening for the tick from the accumulator sphere area (regulator).
Should be 30 seconds or more between ticks, any less and the acc sphere needs changing, and if that needs doing, then the rear accumulator (known as the anti-sink sphere) will also need doing. Do a search for the knack to that one - you'll need a 9mm flare spanner, although you said you did them all so it sounds like you've already replaced it which is good :)
1.9TD+ SX Xantia Estate (Cassy) running on 100% veg
1.9TD SX Xantia Hatchback (Jenny) running on 100% veg for sale
Laguna II 2.0dCi Privilege (Monty)

DIY sphere tool
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