DickieG wrote:I now own Bernie's Xantia estate with the pipe mod (its still fitted to the car) but to be honest I can't say that it makes any noticeable difference to the hydraulic system by comparison to the other Xantia's I have which are as standard. Air or more specifically Nitrogen will inevitably enter the system by way of osmosis as it escapes through sphere membranes, especially when there are eight of them!
That's true, but the system is open on the reservoir so all nitrogen that escapes goes to the atmosphere. The problem I am chasing with the pipe hack is "bubble realimentation" - air gets in the system somewhere, and when it returns to the reservoir it gets sucked again from the pump. As more air gets into the system, more and more % of the system gets air instead of LHM.
The hack prevents the bubbles (actually most of the power steering's return flow) to be directly sucked by the pump. Bubbles go up with the LHM, and they disappear on the LHM surface.
At least, that's the goal
My next step is probably removing the security valve to see if it is sticky, and if it leaks to (and more problematic, FROM) the return piping.