SkyDog1971

I've been having some issues with my power steering. Awhile back my pressure hose was leaking so I replaced it. A few months later I noticed my 4runner was leaking real bad. I'd fill the reservoir every other day it was so bad. So I figured I'd replace the pump and go from there. Once I got the new pump put on I could still notice the whining coming from the pump and the reservoir would overflow this time. Even with the cap on. So I did some more research and heard that the reservoir screen can get clogged so I decided to clean it out and was able to remove most of the gunk. So I put the pump back together and still hear that whining sound. I've been trying to find anything and everything I can about the subject and heard bleeding it may or may not do anything, or changing the little O-ring underneath the reservoir. Any links would be greatly appreciated. Ill be the first one to tell you I ain't no mechanic but I do like to try and get my hands dirty when it comes to doing car stuff

RJR

Just one thing to note - what have you been putting into the PS system to replace the leaking fluid? The Toyota PS system requires automatic transmission fluid; if you use standard power steering fluid like you'd use on your Chevy the leaks will just continue to get worse. PS fluid apparently attacks the seals and causes them to leak.

SkyDog1971

I had been using ps fluid until I read about using ATF. Finally bled the whole thing a long with the steering box and it seemed to have done the trick. No more foaming after I shut it off and driving seemed okay. Still whines a little when I press the brakes though. Not sure what that could be.

RJR

I can't tell you the exact reason why it whines when you press the brakes, but they are related. The anti-lock brake controller uses pressure from the PS pump to activate and pulse the brakes. I don't know any more detail than that, however.

SkyDog1971

Well it looks like its leaking somewhere. For the life of me I could not find out where. All the hoses seem okay and it looks like it coming from under the reservoir. Looked at the o-ring but it looks fine. Think ill replace it and see what's up. I mean as soon as I'd pour enough in the reservoir it would empty within 30 minutes.

millball

Not sure about specific years and models, but some PS systems have a sensor valve in the high pressure side that uses vacuum to raise the engine idle RPMs slightly when the steering is turned.
This sensor is known to fail and then aspirate PS fluid into the engine intake manifold.
This may be the cause of PS fluid loss that cannot be attributed to an external leak on models that use this setup.

scope103

Good point, but when that happens the ATF should disappear into the intake manifold (causing, usually, rough running). SkyDog reports seeing fluid everywhere. (Here's a pic of the PS idle-up valve: http://personal.utulsa.edu/~nathan-b...11powerste.pdf , p.46

If it's leaking that quickly, you should be able to stand there and watch it. First, get it cleaned up really well. You can use spray-on engine degreaser, but ATF isn't very "greasy" so you should be able to just use paper towels. Start it up, and then run around and stand there watching it. Don't be afraid to shut it right off and feel for fluid.

No point guessing about leaks.

SkyDog1971

Definitely will do. Just replaced return hose just in case. Didn't see any holes in it but knew it wa pretty old. Just put a new o ring on reservoir an put ps back in. I flushed it before this but may do it again just in case. Ill keep you all posted. And thanks again for all the help from everyone. Love this forum!

SkyDog1971

Ok looks like we are in business. Put ps back in, filled it up, started the engine and turned wheel very slowly. Started to make a bad whining noise so I added more. Felt like there was more air in the lines so I loosened the power steering box nut to let some of the air out. Tightened it down and turned wheels again. No more whining! Put some cardboard under to see if its still leaking and so far so good. About now I'd see a good size puddle building but it seems to be good. Ended up replacing o-ring on the bottom of the reservoir too so I don't know if maybe that was where the problem was or what but everything seems to be good to go just wanna say thanks again for all the help. Really appreciate it