Power Steering Woes!!!!!!!!!!

My 67 has fairly new componets and Ive had all kinds of trouble with hoses. Now I was driving down the road and the power steering went out then came back for a couple of days and now its gone. I have reason to believe that there is trash in the lines. My question is will puting compressed air through the lines hurt the control valve? Is it posable to flush the system by doing this?
 
I took off my power steering valve. It was easier than I thought it would be. You'll need a few pullers to the the center link off. (That's the piece that goes across the car and move from right to left when you turn. The center link has attached the valve and has a total of four hoses. You can get the 4 off hoses once the center link is off the car.

Once you have the center link and valve on a work bench, it is easy to disassemble. Just be careful to watch how it goes back together. You will likely be able to tell if some internal pieces are worn.