Classic/Antique Car Repair: Power Steering/91 Edlorado 4.9 litre engine, bone yard, steering wheel

Question
QUESTION: I have a 91 Caddy Eldorado. I just replace a leaking power steering pump. However, everytime I turn the wheel the car makes a moaning sound. This was not happening with prior to my replacing the leaking pump. The mechanic was stumped---he felt the rack and pinion system is failing and the new pump is sucking in air which causes the moaning sound. Please advise.

ANSWER: Jeff, was the replacement pump new,, rebuilt, or from a bone yard. Do not rule out a defect in the replacement pump. It is possible that the fluid is low or that one of the lines is resting against the body of the car causing a resonance.
Brad

---------- FOLLOW-UP ----------

QUESTION: The pump is new. The groaning/hissing sound is made everytime I turn the wheel either left or right. The fluid level is good (if fact the mechanic put in a special fluid that was supposed to help this problem).

Answer
Jeff, it is time for your mechanic to reach in his tool box and grab his trusty stethoscope. Probe the rack, the hoses, and the pump while you are turning the steering wheel. The stethoscope will pick up the unit creating the sound. What, he does not have a stethoscope? He should have one. And don't forget that just because it is a new pump does not mean that it is not causing the noise. That is why mechanical things are warranted.
Brad