QuestionIs this system pressurized? and i have a whine that i can not make go away, i`ve tried different fluids and changed pumps. please help.
AnswerYes, the power steering system operates at very high pressure - around 1000 PSI, in fact.
The noise you are hearing is most likely caused by an incorrect high pressure hose - few people even in the trade seem to realize that the hose must have a restrictive orifice in the pressure hose - about 12 inches from the bottom end. If you have the proper hose, it will have a larger diameter down to a metal collar which is about 12 inches from the bottom end, then a smaller diameter from there to the actual power steering control valve. Inside that collar is a 0.070" restricitive orifice to prevent the noise you are hearing.
If you have the original hose to look at, you will see what I mean.
I have found that most of the auto parts stores are unaware of what is inside these hoses, and they will simply sell you whatever will fit.
Check your hose to see what you have - if it has been changed, replace it with a correct one (you may have to take the original hose to a hose repair outfit and have them rebuild if for you - make sure they include the orifice at the same distance from the end). I have found correct replacement hoses at CarQuest for many cars of that era - so try them first.
The other hose, the return hose that simply goes back to the fluid reservoir is not involved in this issue.
I hope this leads you to a solution.
Dick
