QuestionQUESTION: Power steering pump (area) is making a lot of noise. It happens at start up and turning (and usual only after everything warms up slightly). I thought it was the PS pump but talked with the Dealer and they recommend changing the reservoir as the filter may be clogged and not supplying oil. I took the reservoir off and flushed out the filter from both sides then filled it up with new fluid. Went away for a day or two then started back up. Noise is getting worse and today I found the fluid running back out the top of the reservoir. Tempted to replace the reservoir and pump. I do not see any oil leaking out the tubes.
ANSWER: There is a technical service bulletin (TSB) indicating that in the event of a humming noise from the steering, the first place to check is the reservoir screen. This is why the dealer has started there. Although you've flushed it, it may be difficult to access all the areas of the screen that need to be cleaned, and it may also be difficult to knock all the debris off if it is there.
I've seen this condition several times. To check, simply drain the reservoir and visually inspect the screen in the bottom by looking through the hole in the top and looking at the bottom near the sides. Typically, you'll see a significant portion of the screen blocked. The fact that you're expelling fluid from the reservoir supports this type of problem.
If you're getting more of a squealing noise, check the belt.
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QUESTION: I took the reservoir off and knocked the screen completely out. Noise is still there also dressed the belt and the sounds is still there.
ANSWER: I'm surprised that you were able to remove the screen from the reservoir. How did you accomplish this considering that the only openings are the fill hole and the inlet and outlet? If the screen has indeed been removed, you'll definitely need a new reservoir now. The purpose of the screen is to prevent large particles from entering the pump and damaging it.
Presuming this is a humming noise originating from the pump, your next step is to check the power steering lines and hoses for restrictions. This will produce exactly the same symptoms as a restriction in the screen.
If there's any question about the origin of the noise, you should first isolate for certain the source. This can be done by taking a long screwdriver and touching various items in the vicinity of the noise and then placing your ear on the other end of the screwdriver. The noise will be loudest when the screwdriver is on the component making the noise. If you've indeed applied belt dressing, this can complicate matters. This compound tends to be sticky and cause the belt to make chirping noises.
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QUESTION: I took my time with tongs (needle nose style) and a screw driver. I planned to change the reservoir so I had nothing to loose. I have ordered a new one. when it gets here I will replace it and then pull each hose off and inspect and blow them down to see if there is a restriction. I will go ahead and change the belt.
I took an long extension and it did seem to be really close to the pump.
Thanks.
AnswerCan you probe the pump body itself with the extension? If the noise is loudest there, it's a safe conclusion it's coming from the pump.
To check the lines, you may need to do more than just blow through them. The power steering system is under high pressure and moves a large amount of fluid in a short period of time, so simply blowing through the lines may not uncover a restriction. You should also visually inspect the entire length of the lines. Keep in mind that there's also a small section of line in the front that acts as a steering cooler.
If you've determined that there is no restriction, then I'd support replacing the pump (presuming the noise is actually originating from the pump).
When replacing the belt, you may also need to clean the belt-dressing-gunk off the pulleys. It'll be relatively obvious whether you need to do this once you remove the belt from the pulleys.
