ok.
finally had the time to replace fluid.
needless to say the one there was dark, kind a brownish. So replaced with the ch11s stuff (green) and cleaned all up nicely (hoses, reservoir)
No change in symptoms. Power steering still somehow hard to turn.
Also, went for a drive (some 20+ miles), after which went to check the steering fluid.
The pressure build up this time was so much that upon removing the cap, the reservoir actually shrunk (visibly!) right when cap was removed!!! And at the reservoir bottom, where the hose goes into the pump, there's a visible moisture around the jubilee clip and an inch below at the hose surface.
So two questions now spin on my head:
1. Would I benefit with a new (upgraded) PAS reservoir?
2. Could this pressure be caused by a worn out pump? In this case i cannot, to my best knowledge, understand if this is even possible, as the effect of a worn out pump would be lower level of assistance (hard to turn steering), not air pressure build up.
As mentioned before, no strange sounds coming from pump. and everything is properly tight with jubilee clips (no chance of air being drawn into the system).
Please advise.
Don’t want to turn this issue into a money pit of attempts of solving a problem without understanding it first.
I already imagined that i could install, as a remedial measure, a pressure relief valve (one way valve with a spring) drilled into the reservoir! (maybe a dumb idea, as then from time to time i would have a purge of power steering fluid coming out in tight corners
)
cheers everyone