97-SC300

iTrader: (17)

when i did my powersteering rack i did not need to reuse that old sensor. i think mine came with a new one.maybe tahts ur problem

BigD026

Between You post and gsrep1's information...this has to be the most informative PS pump thread here.. I've been reading off and on for months trying to determine my problem. I think you or Gsrep1 could set me off in the right direction...

Last Jan. it was Very Cold here(15'F a few days). My car started making a slight noise by the PS pump.
1.) I checked the reserve..it was bone dry. I noticed the lower fluid on the piping below the reserve but not really any on the Alternator(thank God).
2.) I filled it up and the slight sound went right away.

I checked it throughtout the Spring-Summer-Fall and it has not leaked in a year.. However when it gets below 40'F ..it sounds like a Sewing machine..Louder than EVER! ! There is a Ton in the reserve but..I don't know where to go from there? Reading your post on page 1, Since i ran it bone dry last Winter for a few days, do you think i may just have Air in the lines? or do i need to replace everything?


Click on the picture to get the video to start..



Keep in mind, my Steering works perfect..even to this day with the loud noise..
My Alternator is fine as well - no signs of interior lights flickering...or anything like that.

I have not checked to see if fluid is moving around in the reserve.. but i will today.

What should i check Before going through shern's massive "power steering system" rebuild?
Thanks
BIGd

shern

iTrader: (6)

BigD

Damn, that sounds like shiza! Do you drive around like that?

The Lexus power steering system is pretty straightforward. My 1991 Accord with its mechanical speed sensor is more complicated. There is a pump, a rack and pinion, 2 lines and a few sensors.

With that being said, you need to first find out where your fluid is going. If it is not visibly leaking, there is a very good possibility your vacuum assist valve is leaking. It is the unit attached to the pressure line right at the pump. Please see OLT's thread on diagnosis and remedy. I plugged mine up even though it may not have been leaking at all. I didn't want to deal with it at all.

I dare you to figure this one out.........Problem: Power steering fluid dissapears into thin air.

After you do that, I would highly suggest flushing the entire system and cleaning the two filters. There is a filter INSIDE the reservoir tank. If you look into the cap with the fluid drained, you'll see the bottom of the reservoir and the filter area. Do what you got to do to clean that out.

The next step is to clean the filter in the selenoid at the rack. This one will be a little more work. You'll need to get enough clearance to get a 15" crescent wrench with at least a 1 1/2" opening on the selenoid. I picked one up at Ace, it's a big biotch. You can probably get at by removing all 4 mounting screws and releasing the steering shaft from the rack and pinion (1 bolt). Pull the rack away from the crossmember and let it hang. Disconnect the selenoid wire and break it lose with the crescent wrench. Spin it off with your hands and pull the selenoid. I bet $100 it's filthy. Pry the small filter off the selenoid and clean it. Get all the gunk off and reinstall.

Put everything back together and blow out the return and pressure lines with air. This will ensure that all the old fluid is out. Refill with Mobil 1 Synthetic ATF and bleed as mentioned in my previous post.

If this doesn't solve your issue, purchase a pump. I've replaced many bad PS pumps and racks in my time. I probably could have saved a buck if I followed this procedure but oh well. I loved the learning experience.

Give it a try and let me know your progress.

BigD026

Thanks Bro.

I can tell you it leaked from the bottom piping last January - very very slow. Even then..the fluid was nearly dry before i heard the noise. Fournately, bearly any of it leaked onto the Alternator. I was explaining the design flaw to my Girl...Its like Lexus placed a TV under a big aquarium..sure it is ok today..but if the Aquarium every leaks in 10yrs...your TV is Toast.. I still don't know why they didn't design a catch tray or something in the later models 97-00'

Anyways, Its not actually leaking since last Jan - very dry everywhere and i'm not losing any from the Reserve. Just Noisy at below 45'F, then after the car warms up..the sound is nearly gone.. however its still noticable..but not as loud as the video. If the noise was 10/10 in volume in that Video.. it's about a 3/10 volume after i drive around. About three weeks ago, I could hear it over the engine when the Valet started my car the next morning leaving the Casinos.... << I knew i needed to get it fixed very soon..

I Do think i need to attempt to bleed the air out of the line 1st...
I read how to bleed the lines on page 1 and will try it this weekend. I'm trying to be positive here...I hope its just Air in the lines...but wouldn't I have heard it in the Warmer months?

I still haven't found out why it makes that noise when it's cold..and its completely different when 70-95'F ..maybe something contracting - allowing air to get into the pipes -then when it warms up-rubber pipes expand-sealing it back up? just a guess..

shern

iTrader: (6)

Pop the cap off the top of the reservoir while it's running. Leave the level stick in the hole or fluid will gurgle out. If you have air in the system, you'll see the bubble right away.

Again, I recommend flushing and cleaning the filters. Metals and dirty fluids will obviously react with fluctuations in temperature with respect to expansion/contraction and viscosity.

fwynn

iTrader: (1)

Maybe u have a supercharger ;] and u never knew it was there

96dtm850

I have a very similar problem. I just got my power steering completely overhauled; new rack, pump, cleaned out the lines/cooler. There was a lot of metal in the fluid as the previous pump destroyed it self taking everything else with it.

Strange thing is, cold morning, start the car and it'll whine like crazy. Give it like 5 min., restart the car and it goes away. I'm sure it has to do with the temp. change in the fluid. Perhaps not enough pressure in the system when it's cold???

I've bleed the system, left <--> right steering, hold it at full lock for 15 sec.

I'm going to flush the system again, but what can it be???

shern

iTrader: (6)

As mentioned previously, check the filter in the selenoid at the rack as well as the reservoir filter. Could they have transferred over the selenoid without cleaning the filter?

Are you sure the shop put the correct fluid in? We require Dexron ATF fluid for our power steering systems.

BigD026

I checked the PS reserve while the car was parked at idle and there was no movement in the fluid at all. is it suppose to circulate all the time or just when it needs to assist the steering?

I assume it consistantly circulates from the reserve to the pump and back.. since the belt is turning the PS wheel...I could be wrong.. I'm thinking something has blocked the line between the Power steering Reserve and pump. But the power steering couldn't have ran completely blocked off from the Reserve for a year without failing?

BIGd

shern

iTrader: (6)

Fluid should be constantly flowing through the system even at idle and not turning the wheel.

BigD026

Maybe I filled the reserve up really high and the circulation loop is slow(lamar flow) not disturbing the surface?

Should i see some disturbance on the surface of the fluid inside the Reserve under normal conditions? I don't think it's flowing and I'm betting my Pump has dried&burned up. <but my steering is still perfect...
How Strange.
BIGd

Jerzy_Boy

I just changed my pump and bled it, but i'm still getting the whining and tight steering. i'm gonna try the filters now, and flush the system again. It used to whine at idle before swapping the pump and now it only whines if I turn the wheel, so hopefully thats a sign that i'm moving in the right direction and that the rack might still be good.

Jerzy_Boy

aight, went outside got the solenoid off and damn, that thing was clogged like a muthafuqqa. So I cleaned it reassembled everything and bled again. it turns good and the whining is minimal, I'm gonna flush the whole system, since i used ps fluid instead of atf and hopefully that gets it the rest of the way.

tritron

I wonder if that will solve my problem with hard siring at low rpms. When I start the car the stearing works just fine but once it wormup and rpms at idle go down my car is hard to stear at idle.

wwy059

does anyone know a good way to clean the sensor screen. I can see it and understand putting a large cresent wrench on it. I just don't see room to put a wrench on it. Do you have to pull the steering rack to get to the sensor off? Any information to make this easier would be helpful. this is on a 93 Lexus SC 400.