On Wed, 03 Sep 2014 17:06:38 -0500, dpb wrote:

On 09/03/2014 4:28 PM, Tim Wescott wrote:
...

AFAIK, power steering works by having the force transmitted through a set
of valves, that make the thing torque one way or the other depending on
how it's being pushed.

If the valve is clogged, or stuck, it would cause what you see.

Or the linkage broke...
Or the cyl is bypassing in one direction (or one cyl is bypassing on
a dual cyl system (vs dual acting cyl)