B7100 weak hydraulics

[B7100]

hi people, my B7100 has weak hydraulics so I drained the oil and cleaned the screen which was not too dirty.
I then hooked up an hydraulic gauge which showed a pressure of 750 psi
and my WSM says 1570-1710 and can be adjusted by using shims under the relief valve.
Does anyone know if this can be done by just removing the cover held on by 4 bolts that also have a "x" for a phillips screwdriver bit and sits at the front of the control valve? also,what is the purpose of the adjuster screw next to the shim?
Thanks
Dave

 

[B7100]

Nope, Dave, you have to shim under the relief valve. Upload a pic of the screw you are talking about.

Thanks for the reply,does "no" mean I have to remove the whole valve and not just cover #21 to get at the shim.What do you reckon adjuster screw #23 does?
Dave