i need help. 1963 gmc surburan.it came with factory power steering.i have installed 454 .i have installed a mid 60`s power steering pump with new seals. i have had new custom hoses made .i installed seal kit in the control valve .i have installed new seal on the end of the steering cylinder . today is the first day i have tried it . i bleed the steering with the wheels off the ground and tried to adjust the the control valve . it would creep to the right but not to the left.i went for a ride around the block felt nothing. i jacked the truck up and now it would not creep to the right or left now. i have drove the truck for a while with no pump.is there any thing in the steering cylinder that can go out,burn up. do the clinders go bad. no external leaks.thanks