Power steering system noise?

For some unknown reason Toyota engineers decided to put a fine mesh screen inside the power steering reservoir. When the screen clogs up, as is common on a 20+ year old system, the result is cavitation at the power steering pump. Cavitation will make the pump noisy and / or the steering jerky............especially when the van is cold. The best way of fixing this is to flush the system, clean the filter, and put fresh fluid back into the system.

I'm not sure what the factory recommended procedure would be for this, but as long as you get the old out, clean the filter / screen inside the reservoir, and refill with new fluid you should be in good shape. I empty the system by pulling a pressure line from the rack, then start the motor and use the pump to spray it into a bucket or drip pan (warning this can be messy :shock: ). After it's all out, you may wish to put a quart of new fluid in the reservoir just to rinse things out. Leave your drip pan in place and let the new fluid puke out like you did with the old. Don't worry about letting the system run dry (it won't hurt anything).

The tough part in all of this is cleaning the screen /filter inside the PS reservoir. IMO Toyota was not thinking straight when they put that thing inside a reservoir that was not designed to be taken apart :cnfsd: . It can be taken apart and cleaned, but since it involves bending metal tabs, you're probably only going to get away with it once or twice before another reservoir would be needed.

Here are some pics of a reservoir I took apart for cleaning of the screen / filter.
http://i8.photobucket.com/albums/a23/timsrv/01-4.jpg


It's tough at 1st to unbend these tabs. I used a 90 deg scribe from the side to get them started. It takes some force and some patience, but once you get it to this point a large slot tip screwdriver will finish the job with ease.
http://i8.photobucket.com/albums/a23/timsrv/02-3.jpg


This particular reservoir came from a salvage yard and sat around dry for a while. Yours will probably look a little different inside.
http://i8.photobucket.com/albums/a23/timsrv/03-3.jpg

I used a big bucket and some mineral spirits paint thinner to clean. I poured the paint thinner in the bucket, then threw the parts in and sloshed it around. I took the parts out and blew dry with compressed air. I ended up putting the reservoir back in the solvent/thinner and I repeated rinsing/drying until I was satisfied with the results. That spot you see is a stain on the bottom of the reservoir (not junk on the screen).
http://i8.photobucket.com/albums/a23/timsrv/04-3.jpg

Re-crimping the reservoir lid.
http://i8.photobucket.com/albums/a23/timsrv/05-3.jpg

All ready to be installed.
http://i8.photobucket.com/albums/a23/timsrv/06-2.jpg

When it comes to filling back up, Toyota calls for Dexron II (which is NLA), so Dexron III is the next best choice. Stay away form the newer Dexron fluids (like Dexron VI) as they are synthetic and may or may not be compatible. This is a recirculating system and is also self priming / self purging. This is nice because there is no need for any special care when refilling or servicing. Once the pressure line is hooked back up just start the engine and start filling the reservoir. The pump will suck the ATF easily. Pause every few moments and listen. When the pump stays quiet without you pouring, shut off the engine and top off using the dip stick inside the cap. Start the van again, turn your steering wheel from stop to stop (to get any errant air bubbles), shut off and recheck fluid level. Add more fluid if required and you're done!

If you are cheap and lazy, and only care about shutting up that noisy pump, an alternative way (short-cut) could be to forget about everything I just said and simply poke holes in the reservoir screen with a screw-driver :LOL2:. Of course this is defeating the purpose of the screen and you would be releasing all the grit previously captured back into the system. This method would also most likely shorten the life of your power steering system. Have fun. Tim

PS: Since you're servicing your power steering system anyhow, it might be a good idea to check the pump for leaks and repair (if required). Here's a couple of good threads on that:
http://www.toyotavantech.com/forum/s...-Steering-Leak
http://www.toyotavantech.com/forum/s...alot-of-fluid!
https://www.toyotavantech.com/forum/...-steering-pump

There seems to be a fair amount of room beside the PS reservoir. Wonder if it's possible to put an inline filter in the PS pump suction line? It's plenty long. Have to look at doing that...

Just keep in mind that this is a suction line and any restriction here will make the pump more prone to cavitation. I think that's why they put it in the reservoir (the best location with most surface area for a screen). It's just too bad they didn't make it easy to access. I'm not saying an in-line filter wouldn't work, I'm just saying restrictions on suction lines are not good. Tim

I think my pump is leaking and it's noisy as hell and a little jerky when cold. So I bought the seal rebuild kit from RockAuto like mentioned in another thread. And am going to replace all the seals and clean out the screen and bleed it a few times.

If that doesn't fix it, then f*&k it. My first 2 Toyotas never had power steering. That's how I can crush pecans with my fingers. :lol:

Will update hopefully soon with progress.

I think I am going to try this. Where exactly is the hose you pull to drain? Not a 100% sure where the rack is. :dizzy:

The rack is a few inches in front of the bottom of your radiator. These lines can get rusty and stuck so be sure to use a tubing wrench. If these lines are too rusted, rather than risk damage you may wish to forego the flush. The screen in the reservoir catches most of the particles anyhow, so just cleaning that should be good enough. Tim

I just realized I need to get that big expensive hose before I attempt this because I have a feeling mine will crumble.

Question: Is all ATF Dex II red in color? The reason is. My reservoir was really low so I put fluid in (ATF Dex II -red) and now when I check it it isn't so red. I think the stuff that was in there was brown because now I have redish goldenish brownish.

Dexron II was red but is NLA. Dexron III supersedes Dexron II so use that. Anything running for 25+ years in a closed system will turn brown. A system flush is preferred but if you have stuck pipes on the rack I wouldn't worry about it...........just cleaning the filter should be good enough. Tim

Looks like some spam got in. Anyway it reminded me to follow up on my power steering noise. It turns out it was the alternator because when I replaced it the "power steering" noise magically went away.

Most high mileage vehicles seem to have a whiny power steering pump so maybe I should be used to it but it is highly annoying. Is there any way to get rid of the noise without a completely new power steering pump?

:silvervan::redvan::yellowvan::greenvan:

It means you are not getting enough fluid to the pump either because

1. not enough fluid / you have a leak
2. a restriction in the system - a kink in a hose, dirty filter, a contaminated hydraulic system
3. air getting into the system - a hole in a return or reservoir hose allows air into the system.

With that said, I think the power steering systems on old Toyotas are a bit week. I've never had this level of power steering problems on any other vehicle I've driven.

Quote:

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Originally Posted by Cornato

I think my pump is leaking and it's noisy as hell and a little jerky when cold. So I bought the seal rebuild kit from RockAuto like mentioned in another thread. And am going to replace all the seals and clean out the screen and bleed it a few times.

If that doesn't fix it, then f*&k it. My first 2 Toyotas never had power steering. That's how I can crush pecans with my fingers. :lol:

Will update hopefully soon with progress.

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I have thought about running my van without power steering so that I don't have to deal with the leak - just drain the system, pull the belt and be done with it - but the steering rod and U-Joints look pretty small to me. On previous vans those U-Joints have even had play in them. Any thoughts on how much stress manual steering would put on the 25+ y/o steering linkage parts?

That's a good point. Running without power steering increases stress on the moving parts ahead of the rack. These vans aren't known for heavy duty parts here. In fact, there was a recall due to gearbox failures. That being said, I've run these without power steering before and things seemed solid enough, but that just was a temporary thing. It's conceivable that running that way long term could create a safety issue. Tim

In a previous post I reported the PS hose was dry rotted and broke off in my hands… so why not search the forum for tips and Timsrv had a great post filled with instructions on how to clean the screen in the PS reservoir Tim if you read this you were right on undoing the tabs will make you want to take the easy way out but I kept my patience and it was well worth it, the screen looked like it had coffee grounds embedded in it also I didn’t undo the pressure line at the rack but I did empty the system when I removed the reservoir I simply placed a small jug in its place and collected the goop there no wonder the PS pump wines the fluid is like loose mud….. the rest went just as you said I’m glad I didn’t resort to poking holes in the screen Thanks for sharing your technique. Ralph
Attachment 1813Attachment 1814

I did this same thing a couple of years ago but when I looked at the lines at the rack there was no way in hell I was going to disturb that mess of rust and scale. I did flush the system but did it a little differently.

I took the feed hose to the reservoir and re-routed it into a large waste jug.
The suction hose got routed into a large jug with fresh fluid.
It was a little messy but worked well enough and saved the headache of messing with the hard lines.
BB

I keep forgetting that some of these vans get messed up with rust here. They don't salt the roads here so my vans typically stay pristine in these spots. Tim

Sounds like paradise to me.
I can't imagine what it would be like to live in a place where things don't rust.

I live in a land where most cars do well to see their 10th birthday and 15 is considered "ancient".
I can count the number of pre `95 DD's around here, on one hand (and 3 of those are mine).
BB

Most people around here dump cars after 10 - 15 years too, but it's not because of rust. Usually it's neglect or them just wanting something new. Like the 06 XB I checked out on Saturday. Had 95k miles on it & still the original coolant :dizzy:. I'm guessing the gear oil was original too. Tim

Im in a little bit of a bind here. This problem started out when I accidentally added oil to my power steering reservoir. Luckily, it didn't take much at all before it was topped off, and something raised a red flag in my head and checked the manual and UGGGH wrong one. I'm also lucky I never started the engine. I removed the reservoir, completely cleaned it out of all gunk. This actually turned into a good thing and now my reservoir and screen is nice and clean. However, I was reading about what kind of fluid to add to the reservoir. Tim, you recommended Dexron III, but this post was from 5 years ago. Now I guess you can't find Dexron III anymore (at least according to the guy I talked to at autozone). He did say that Dexron IV was in now and they make synthetic and mineral versions of it. My bind that I'm in now is that I need to get to work and this is my one and only vehicle. I am going to head to autozone and pick up the Dexron IV. You had mentioned to stay away from Dexron VI (6). Did you mean Dexron IV? Under the time limit I am currently under, I need to get something to put in there. The Dexron IV mineral seems like my best bet for now, so I'm going to add it. If you think its a bad idea though, I may end up draining the system and refilling it with something better. It can't hurt to flush it anyways eventually, but let me know if you have any input on this.

If there is a Dexron IV, then I'm unaware of it's existence. Of course I buy in bulk and only buy every 5 years or so, so things could have changed. I am also unaware that Dexron III has been discontinued and seriously doubt that it has........but again, I could be wrong. Whatever you purchase, just make sure it's backwards compatible and will mix with Dexron II & III. Tim

I used DEX/MERC from Advanced Auto and it's working fine. Ralph






Attachment 2482

Yes, anything that says Dexron III compatible is good. I always feel better when it says Dexron II compatible too, but since Dexron III supersedes Dexron II, then I can accept it's worthiness :wnk: :wrthy:. Tim

Ok. I was a little confused at first with the roman numeral system. I know that VI means 6, but in the natural numeric order, I thought you were referring to 4 because it superceeded III. Funny enough, the guy at Autozone made the same mistake and said they only carry dexron 4, but when I got there, all they had was dexron VI. I figured out that it was exactly like you said - dexron VI. Anyways, enough of the numeric confusion.

What I bought was Autozone ATF Dexron VI (also says GM compatible) When you said it should be backwards compatible, I freaked out a little and hoped that a transmission flush wasn't something I had to now worry about, but I read the back and sure enough it says "This fluid is also suitable for use where Dexron II, Dexron III, JasoM315, Toyota WS or Toyota T-IV fluids are recommended."

Phew....

I got about 550 miles into my first trip from Council Bluffs, IA back to Fort Worth and my power steering pump started whining. I figured that it was low on fluid so I pulled over and bought a quart of Dexron III to add. When I pulled the cover off of the access panel I saw that ATF was coming out of the reservoir all around the cap. The cap was tight so it was just blowing past the seal.
The pump itself was dry as a bone on the exterior and so I could only surmise that it had failed internally from sitting for so many years. I ordered a new pump and installed it in the van in the hotel parking lot last night. The new (remanufactured) pump from Autozone whined a bit and doesn't work properly. It feels as though I don't have any power steering at all. It doesnt whine and it runs quiet but it is still blowing ATF past the reservoir cap seal.
I did a search on the forum and about the only thing I could see was possibly the filter screen in the reservoir being clogged, however I would think that if it is blowing fluid back out the reservoir that it would push the stuff back up and out of the screen unless the fluid being pushed out is coming from above the screen already.
I have a 1900 mile trip ahead of me in a week and a half and I want to have this fixed before I go. Help?

New (remanufactured) pump
new belt
Fluid not flushed before installation
Reservoir not removed and cleaned out
43,000 miles (total) on van
Fluid blowing out of the top of the reservoir past the cap seal
No power steering felt at the steering wheel
pump not whining

Can someone post a picture of where the drain on the rack is? I would like to get at it when I remove the reservoir this afternoon.

I'm not aware of a drain, I always just took a line off it.

Sounds good. So the line coming out of the bottom of the reservoir and going to the top of the pump is the low pressure inlet and the line with the banjo fitting at the bottom of the pump going to the rack and then back into the side of the reservoir is the high pressure return side, right? This would make sense if the screen were clogged. No ATF would be getting through the screen, and everything returning would be returning above the clogged screen and have nowhere to go but up through the cap. Sound logical?

Yes, all you just said is correct. Of course I haven't seen it coming out the cap before. If the screen is clogged, there will be cavitation at the pump, so the volume it moves will be reduced to whatever can flow through the screen. Because return flow and output flow are matched, it shouldn't overflow unless it's overfilled..........although I suppose that's possible in some situations. A clogged screen & pump cavitation typically result in diminished/jerky performance when system is under demand (maneuvering in tight quarters) and the pump will make noise. Tim

Problem solved. My troubleshooting worked.
Here was the problem:
The reservoir screen had become completely clogged from sitting for such a long time. It had a black, tar-like goop completely covering the screen of the reservoir. So the pump would attempt to draw fluid down from above the screen but could not due to the blockage. The return line was above the screen and was doing its job and returning fluid to the reservoir. Since the screen was blocked, fluid wouldn't go through it and adding fluid only made it overflow faster. This would cause it to vent out past the cap as that was the path of least resistance (thank God, better than the middle of the high pressure-return line) and wouldn't let the pump operate properly.
This is a very simple power steering system. The filter screen in the reservoir is truly the Achilles heel of the system. I think that Toyota expected people to occasionally remove the reservoir and flush it out, and that's why it is so easy to remove. I wasn't able to get the tabs pried back to remove the cover so I just bought some good chlorinated brake cleaner and filled the reservoir up, agitated it, scraped as much tar off of the screen as I could with a flathead screwdriver, and repeated the flush a few times until it was clean. I then let it dry, and ran a bunch of Dexron III through the reservoir to purge any remaining solvent out of it. Two 12mm bolts and two hose clamps and the reservoir comes out. Easy as pie.
I did all this in the hotel parking lot and the only casualty were a few white hotel towels. Real "field maintenance".
The power steering system now works properly and as intended.
Time to get the AC charged up (anybody know if shops still use R12?) and I will be ready for my road trip!

Wow, I've never seen one clogged so thoroughly. Over the years I've had a few that started making noise, and that was my cue to clean that screen. So now we know the reservoir will overflow if the screen gets bad enough :)>:. That's awesome you got it fixed.

I'm sure there's still some shops that do R-12. I stocked up on that stuff a few years back. I also got a high end R-12 recovery/recycling machine when they were practically giving that stuff away, so I'm set for life. When I replaced the compressor on my van 2 years ago I was able to suck it all out, run it through my machine in the "recycle" mode, replace my compressor, then put it back in :thmbup:. Today we broke a temperature record (was over 80°) and I was cruising in style with my AC blasting :dance2:.

Next time I run that machine I'll have to takes some pics, perhaps a video, and make a thread. BTW, the experts say that converting over to the R134A is the best way to go, but I like my R-12 (too set in my ways to change now). Tim

Howdy everyone! Long time reader. First time poster. Proud owner of Luna Cos Mika, 1988 2wd
nice to meet ya'all.

Power steering pump overflowing:
Here is what is happening. When I turn the vehicle on there is a loud noise from the area of the power steering pump after letting it run for a couple minutes I turn the vehicle off, and the reservoir Starts permitting fluid to bubble out.
My apologies if this has already been covered, I tried to search but the service does not seem to work well with my iPhone. Thank you so much for your help

I was able to get the reservoir off, and indeed it was very mucked up. The problem now, is that the inner screen appears to have come loose and all but one tiny section. My next question is, if I put it back together with the screen as is, how long before terrible things happen? And if I need a new reservoir, do you know if they are still available? Thank you so much

I hate to bring this thread back from last year, but I think I am having this problem now with my 1987 2wd Van. Though I am more than happy to do the work, what is to prevent this from happening again down the line after I clean out the screen? With that in mind, is there any type of replacement reservoir that anyone has tried that works more efficiently/ doesn't have this problem?

I've had this problem on 3 vans now, all with over 150k miles. Cleaning the screen took care of the issue on all 3. 2 of them don't get driven much, but the 3rd is my daily driver and I've driven it almost 100k miles since cleaning and the problem has yet not reoccurred (knock on wood). Keep in mind this is a closed/recirculating system, so unless you introduce foreign material when adding fluid, there's not really anything to clog the screen. As the system wears it will produce some debris, but unless you have a component failure, I think you're looking at 10+ years and over 100k miles before it should become an issue again. Tim

I bet mine probably needs to be cleaned, it makes a whine on tight corners. Where is the screen located exactly? In the reservoir? Do you remove the reservoir to clean it? Thanks for the tips.

EDIT: I just saw there was a 1st page to this thread - cleaning the screen was literally the original topic! Now I feel like an idiot. Sorry guys! :doh:

Quote:

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Originally Posted by timsrv

I've had this problem on 3 vans now, all with over 150k miles. Cleaning the screen took care of the issue on all 3. 2 of them don't get driven much, but the 3rd is my daily driver and I've driven it almost 100k miles since cleaning and the problem has yet not reoccurred (knock on wood). Keep in mind this is a closed/recirculating system, so unless you introduce foreign material when adding fluid, there's not really anything to clog the screen. As the system wears it will produce some debris, but unless you have a component failure, I think you're looking at 10+ years and over 100k miles before it should become an issue again. Tim

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Thanks for the insight Tim! I will update when I complete the work.

I will be the guinea pig for having no screen.
I think it was already damaged\gone.

I replaced the fluid. Was very dark.
Drain and repeated a week later.

Been a few months and no whining.

You have a tremendous amount of information here that helps with other Toyota vehicles (not just vans,) notably: my 1993 Geo Prizm (Corolla clone) which has that stupid screen mesh at the bottom of the reservoir along with a diffuser. Since I have the mechanical aptitude of a German Shepherd, I have deferred all my maintenance to a capable mechanic just across the border in Acuna, Coahuila Mexico. Apparently, the Mexicans don't seem to have a clue about this screen mesh problem, and I was wondering if any of this information was available in Spanish. All the Spanish language videos that I have been able to find deal with flushing the fluid properly, but remain mute about cleaning the screens. I've tried to tell this guy, but I had to threaten to get another mechanic until I finally got his attention. Any Hispanics out there? I would appreciate any help. Muchas gracias por ustedes ayudos. (And I apologize if I screwed that up, my Spanish is only slightly better than my mechanical aptitude.)

Quote:

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Originally Posted by timsrv

Yes, all you just said is correct. Of course I haven't seen it coming out the cap before. ... ... Because return flow and output flow are matched, it shouldn't overflow unless it's overfilled.... .....although I suppose that's possible in some situations. . Tim

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well, I've seen it now... ...Wednesday night, I pushed a little bit sideways on the (molded) steering-fluid return hose, so I could check my engine oil ... ... Started it up yesterday morning, and, I noticed some steering-pump noises, so, I shut it down to look around. It turns out the garage floor has a red puddle of steering fluid. I examined the van for the source of the leak and found 2 wet areas.

Firstly, it was a bit wet where I found a sneaky crack in the underside of the factory return-hose...(a dry + weak spot in the old hose that finally let go after being shoved out of the way for 31 years to permit easier access to the engine-oil dipstick)

Secondly, the whole reservoir was soaked. And, the reservoir was topped out, "bubbly", and had obviously been blowing out through the closed steering fluid cap !!!

My thought is that, the crack in the return hose may have been pulling air into the system and, the pressure of being "over-filled" (because of the extra air), causes it to blow out of the cap.

So, one thing to check if you ever find your reservoir filled to the top and overflowing from the cap is the airtight condition of your return lines.


Solution: new return line for power steering fluid.



https://parts.evanstoyota.com/images...051_44348A.png

Part Number: 4434828040


didn't feel like waiting for the part, so, of couse I used "gates" bulk 5/8" hose---
didn't like the way bulk hose wanted to route itself, so, I made this too--

Attachment 6954

Yes, the pump sucked air, whipped it into the oil, compressed it, then it expanded when it came back to the reservoir. Result = messy overflow. Keep in mind there are different grades of hose. Some are intended for hot antifreeze and some are intended for hot oil. If you used heater hose for this it may or may not hold up. Always best to use the stuff that's made to do the job. The good news is there is only low pressure/low stress on this particular hose. Very creative with the copper BTW :wnk:. Tim