Earlier this year I replaced the power steering pump on my '84 Trans Am. I also replaced the pressure and return lines since I cut the old lines after they wouldn't come off. They were rusted and stuck and I've got a short temper sometimes!
Anyway... There is SOMETIMES a lack of power assist while driving slowly and turning sharply. I've bled the system numerous times, but can't find why the steering is as stiff as it sometimes is. It has felt at times like there is manual steering!
My steering box was also slightly worn before the pump change, and I've noticed a larger 'dead spot' at center. As a quick fix, could I adjust the box to tighten it up a little more or have most of you had to buy an entire new box?

 

'84,

The amount of lash in the steering gear is not directly related to the hydraulic assist of the box. You can adjust the lash to reduce the "play" or "dead spot", but that won't change the assist force.

Hydraulic assist force is dependent upon good seals in the pistons at either end of the box, free-moving steering components (greased it lately?), and hydraulic line pressure. If the pump you installed is the correct one for the car, the volume and pressure should be correct, and assist should be fairly constant. However, if the pump RPM is too low from either belt slippage, low engine RPM, or underdrive/incorrect sheaves, your assist force may be low and steering effort would be excessive.

Just some things to check.