I suspect that the pressure relief valve of my F1 unit is bad. Does anybody know where it is located? Looking at the unit I find two screws: One at the top (A) and another next to the solenoids (B). See attached picture. Is one of them the pressure relief? Thanks for your help! Image Unavailable, Please Login
Looking at the hydraulic schematic in the workshop manual (page D20), the relief valve is towards the top end of the unit, in the middle. If you had to guess, "A" would be the likely one. What's that circular item below the "A" in your photo?
Loss of pressure in idle (i.e. no solenoids actuated). The pressure releases through the return line, so its not the check valve. That was an educated guess and you're absolutely right! The screw contains a spring loaded ball, which acts as the relief valve. You can adjust it by turning the inner part. The outer part (i.e. the screw nut) is just there to hold things in place. Moreover the screw is also part of a check valve: the top of the screw compresses another spring which presses against another ball. Well, I don't know the english term. Its there to seal the cross hole which was necessary for manufacturing purposes.
Is your accumulator good? Is it over 10 years old? How long have you owned the car? If atleast 10 years have you ever notice the hydrauic oil getting a bit creamy looking or foaming?
