Power Steering whine and bubbly fluid

[pugsy]

Have a 92 XLT and the power steering is fine when it's cold, but when she warms up, the power steering whines when I turn the steering wheel and I can feel some feedback like it's not going smooth. I still have power assist but it sounds awful. And when I open the power steering resevoir to check the fluid (I have ATF in there) after it's warmed up, it's kinda cloudy and bubbly.
Any ideas what's going on in there & how to fix?
Thanks!

 

[BrooklynBay]

Try draining out the fluid, add a drop of Lucas P/S stop leak, and conditioner, and use synthetic ATF. If you use too much Lucas, it will create the same symptoms as you were already having in addition to having fluid pouring out of the reservoir.

 

[Bill Kemp]

Whats wrong with useing power steering fluid?
Agreed that Lucas makes good stuff. It extended my pump & rack for a year or so before replacing on the 96X.

 

[BrooklynBay]

If you could find synthetic P/S fluid, then use it. It's easier to find synthetic ATF. ATF also has detergents for keeping your system clean. Some ATF, like Mercon V is semi-synthetic, and contains friction modifiers. Check this link about the various kinds of ATF: http://www.explorerforum.com/forums/showpost.php?p=1348273&postcount=10

 

[ma96782]

Mine made noise when I over filled it.

Though, it wouldn't hurt to draw off most of the fluid (turkey baster) and add fresh new fluid (be it p/s fluid or ATF). I used p/s fluid as I already had some, on hand.

Use the fliud marking on the dip stick............note: one level is hot and one level is for cold fluid.

Aloha, Mark

 

[Bwana Bob]

My 92 uses type F ATF. I don't know if Mercon is acceptable.

It sounds like you have air in the system. Check for leaks, then try the air bleeding procedure.



Bob

 

[pugsy]

how do you do the "air bleeding procedure"? If I suck out most of the fluid and refill with fresh or better fluid, would that work?

 

[glfredrick]

Generally, the louder the whine, the more air is trapped (in bubbles) in the fluid. That air will also eat your pump. The technical term for this is cavitation.

You only get air from one of two sources -- a leaky line or a low fluid level that exposes the intake to air. In your case, I'd check for both.

I just did a power steering job on a Ranger where both lines were rusted off, one totally the other full of pin holes. The truck came in with a "whining" noise complaint with a "hard steering" issue. I guess. As far as I could see, that pump had not held oil for a LONG time.

Also, when you first fill your system, you have to do a slow turn from lock to lock several times. This purges the system of air, but it will not take the bubbles out of the oil. For that, you have to just let it sit for a while without running until they work themselves out of the system.

 

[unclemeat]

FYI cavation is the condition in a system where the pressure in a fluid is reduced due to high velocity to below the vapor pressure of the fluid, resulting in the sudden boiling (a liquid changing to a gas or the formation of bubbles) within the liquid and then the collapse of the bubbles when the pressure returns to above the vapor pressure. When cavitaton occurs within a pump, the action of forming bubles and the subsequently collapsing, it creates pits on the impeller/propeller. The result is that the cavation is a violent process that will destroy of the impeller. If cavation is occuring within a power steering system it is simply a matter of time before it completely destroys itself. Cavation is certianly possible, however it make a lot of noise. I think it is more likely that you have some leaks and air is getting in. If I am not mistake the resevior of a power steering pump is in a negative pressure (sucking) condition.

 

[pugsy]

This cavation sounds like what's happening. When I drive for a while and things heat up, it makes a lound whinning noise when I turn the wheel just even slightly. I went to look at the fluid level and the ATF was almost foamy bubbly. However, once it sits for a while and cools down, the fluid looks normal again it's fine and doesn't whine when I drive it the next time untill it heats up a lot again. The power steering system doesn't leak so I wouldn't think there are any holes in the lines. How can I fix this cavation so it doesn't totally wreck my power sterring pump?

 

[badgett]

All you have to do is add the Lucas to the fluid that's in it. It will stop the whine instantly. Money back guarentee if it doesn't. Tried alot of things to make my pump stop whinning. Lucas was the only thing that worked. That was about 5 months ago. Still no whine.

 

[pugsy]

Will the lucas prevent the cavation that is referenced above? how does it take the air out of the oil?

 

[BrooklynBay]

It doesn't take air out of it, but conditions, and swells the seals. You shouldn't use too much, or it will start to expand, and blow the P/S cap off.

 

[unclemeat]

Lucas wil not prevent cavation.

 

[pugsy]

I've used a stop leak additive before and it blew out the seals! had to get a new p/s pump. There's no leaks currently, just cavation - i just need to get the air out of the fluid somehow. Any ideas how to do this?

 

[BrooklynBay]

Drain out your old fluid, refill the reservoir with new fluid, and turn the steering wheel from side to side several times until the noise goes away.

 

[glfredrick]

Drain out your old fluid, refill the reservoir with new fluid, and turn the steering wheel from side to side several times until the noise goes away.

Cavitation can only come from a source of air entering the oil -- which means a leak or pinhole somewhere.

Lucas will swell the seals a bit to stop seal leaks. It can't really help a more major leak like a line or fitting. It also conditions the oil somewhat modifying its viscosity, which can also help to make it more resistant to bubbles. Otherwise, it can't stop cavitation.

It is actually likely that your pump is bad. You can try changing the oil, that is virtually a free fix (oil is cheap enough to not matter in the big picture) and if it quiets your pump, you are all set. If it doesn't then prepare to change pumps. Remember -- a new pump is not always a good pump. A pump that works correctly is a good pump, so it doesn't really matter if it has been changed recently.

One other issue that you might be having is overheating of the oil. I run a cooler on the power steering line on my off-road truck. You can get one at almost any salvage yard for a couple bucks and plumb it into the LOW PRESSURE LINE (the one held onto the back of the pump with a spring clamp -- NOT the one that threads into the pump!). Use transmission cooler line of an appropriate size to do the plumbing. It is fairly simple to hook up. Get the cooler into the airflow somewhere. Shouldn't cost you more than $20 or so to do this mod.

 

[pugsy]

Thanks for the tips. One thing I did notice is that there was excess fluid on the top of the dipstick cap (like it bubbled over). Is the cap supposed to be air tight? ie, not allow any fluid out the top of the resevoir when it heats up and expands? If it is, then I think that might be my air source to the fluid, not a leaky line. If it's supposed to have a hole and let fluid escape (in the event you overfill it), then I don't know where the hell the air is coming from. I might try sucking out the fluid and putting in synthetic stuff to prevent overheating of the fluid.

 

[unclemeat]

Cavitation can only come from a source of air entering the oil -- which means a leak or pinhole somewhere.

Your not understanding, cavatation is a spontanious boiling of a fluid, due to negative pressures effects within the pump chamber. A leak would increase negative pressure and deminish the chances of it occuring. Cavitation does not involve air. It is the fluid changing state from liquid to gas and back to liquid at constant temperature. If you have cavation in your pump it will destroy itself in no time.

I wonder what is the temperature of the PS fluid, is the cooler functioning properly? If the temperatre is high enough cavation may occur.

 

[glfredrick]

Thanks for the tips. One thing I did notice is that there was excess fluid on the top of the dipstick cap (like it bubbled over). Is the cap supposed to be air tight? ie, not allow any fluid out the top of the resevoir when it heats up and expands? If it is, then I think that might be my air source to the fluid, not a leaky line. If it's supposed to have a hole and let fluid escape (in the event you overfill it), then I don't know where the hell the air is coming from. I might try sucking out the fluid and putting in synthetic stuff to prevent overheating of the fluid.

The hole is supposed to be there. It is a breather vent. If you are slinging oil out of it, then you are either too full, or full of air bubbles.

I'd pull the drain line and let all of the oil run out. Refill with fresh. Synthetic is good. I like it and run Amsoil in most of my stuff. I still think that it is very likely that your pump is gone. They're only $50. I'd replace it.

Uncleanmeat, I hear what you are saying about cavitation, but I've worked in hydraulics for years and the air leak mimics the effect so I use the term in both directions. I've rebuilt enough pumps with torn up impellers, rotors, or pistons from leaky o-rings on the suction side to know how that it works the same way for all practical purposes.