Noisy after Steering pump replacement in '90 90 20V

[benswann at comcast.net]

I recently replaced a bad steering pump that had seized in a '90 90 20V with a
rebuilt unit from one of the commonly used reputable suppliers on the list.

The pump/steering system is noisy with the high pitched type of noise that
occurs when steering is turned full lock eminating when turning at any position
in range of travel.

Is this a bad rebuild or is there something else to look for.  System was fully
purged and filled with new Pentosin 11S as specified.

Ben