What is the working pressure of the Hydractive 3 & 3+ systems?

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Jay-Bruce
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What is the working pressure of the Hydractive 3 & 3+ systems?

Post by Jay-Bruce »

Hi, just out of curiosity, I'm wondering what the hydraulic system's working pressure of these cars is?
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GiveMeABreak
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Re: What is the working pressure of the Hydractive 3 & 3+ systems?

Post by GiveMeABreak »

The hydroelectric pump operates at 140 bars, 0,7l/min, at 2300 rpm.

The Overpressure valve operates at 180 bar.
aerodynamica
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Re: What is the working pressure of the Hydractive 3 & 3+ systems?

Post by aerodynamica »

Quite similar to the original LHM system pressures. Main difference is that the pump runs (I think) at that one speed whereas the LHM system with its engine- driven pump runs at a range of speeds and that's why the old system needed its pressure regulator and in some, flow divider. It's interesting to me because I daydream about classic citroen electric conversion and wonder if adapting a GS or DS to use the BHI unit would be more efficient. Far more difficult on flow divider equipped models like XM and BX because that set up relies on a constant flow. Also I think the BHI is designed to operate infrequently and so having it kick in every time the steering is moved would probably give it a short life. Anyway it could still be done with the appropriate change of seals for use with LDS
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GiveMeABreak
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Re: What is the working pressure of the Hydractive 3 & 3+ systems?

Post by GiveMeABreak »

The later system uses a series of inlet and exhaust electro valves in the BHI and hydraulic blocks, so the electronic pump rarely runs except to maintain the height occasionally and for raising operations, which is another main difference.