I have a bladder type pressure tank,the tank will pressure up to 35# and cut off like it suppose to,but it won't go any higher,if I turn the screw to try to get it higher,it will run constantly yet never get any higher.is the tank bad,or is it my well pump?

With the power off and the pressure bled off what's the bladder tank pressure set at?
Back to you, Tom

Is your pump a jet pump (above ground) or in the well?