Power steering fluid causes rack failure...

[idosubaru]

1996 Impreza. A friend had a leaking pump and replaced it. Unknowingly he added power steering fluid instead of ATF to refill it. It had problems from the start and he finally saw that it was supposed to be ATF. He flushed and filled it but said the power steering is like %70 now and hasn't gotten any better over a few days. He even swapped in his old pump (since it worked fine) just to be sure that wasn't the cause, same symptoms.

 

He's bled and flushed the system and it's never taken me more than 30 seconds to bleed power steering lines so I dont' think that's it.

 

So the power steering fluid caused the rack to fail? Nothing to do except replace the rack then right?

[bheinen74]

Doesn't the cap/lid to the ps resevoir say what fluid to use on it?

[Fairtax4me]

Doesn't seem like it would make that much difference but the different fluids can react differently with the materials used in the system (hoses, metal components, bearing protection) I think I'd be looking at other sources of binding before replacing the rack. How about the U joints in the steering shaft? Are they well greased?

[idosubaru]

Since it happened as a result of replacing the pump I wouldn't think it's the ujoint. Seems like it would be strange to have a perfectly fine steering, replace the pump, then the ujoint is bad the second you start it up. He said he's just going to live with it for now, it's not bad enough or causing any issues to warrant repairing. But someday he'll probably get around to it.

[johnceggleston]

Since it happened as a result of replacing the pump I wouldn't think it's the ujoint. Seems like it would be strange to have a perfectly fine steering, replace the pump, then the ujoint is bad the second you start it up. He said he's just going to live with it for now, it's not bad enough or causing any issues to warrant repairing. But someday he'll probably get around to it.

 

i have a 97 GT with steering stiffer than my 97 obw. i wonder if the po used the wrong fluid.

 

when you bled the old out, how did you do it?

 

thanks,

john

[idosubaru]

he's in Georgia and I'm in WV so I'm trying to help him remotely and i'm not sure. he followed the FSM and just cracked the highest hose or whatever at the steering pump enough for it to drip fluid...something like that.

 

does the same thing with the new pump and old pump so i don't think it's pump related since the old pump didn't have any problems prior to this.

[Fairtax4me]

I wonder if there is some obstruction in one of the lines. Maybe one of the hoses is collapsing internally?

[idosubaru]

I wonder if there is some obstruction in one of the lines. Maybe one of the hoses is collapsing internally?

Not sure how to test that, probably a pressure gauge but i'm sure he's not interested in messing with that.

[WoodsWagon]

Why was the pump replaced in the first place if the old one was working fine?

 

Stiff steering is usually the u-joints on the coupler between the rack and the column. Spraying some penetrating oil on them can loosen them up for a bit, but it tells you they need replacing.

 

If the car was in an accident, check for kinked lines on the rack, the engine crossmember, and where they run over the head to the pump. Hoses don't usually collapse, they're under pressure. The metal lines can get crushed though.

 

Racks rarely fail, and when they do, they leak.

 

Using the wrong fluid, PS vs ATF vs Engine oil won't hurt anything. Honda's are finicky about that, and subaru XT6's with the Cybrid steering are, but the rest have no issue with it.

 

Turning the steering lock to lock a bunch of times is the usuall way of bleeding it. The bubbles surface in the resevoir and fluid gets sucked into the pump.

[idosubaru]

I covered most of your suggestions in the opening thread:

Why was the pump replaced in the first place if the old one was working fine?

A friend had a leaking pump and replaced it.

 

Turning the steering lock to lock a bunch of times is the usuall way of bleeding it. The bubbles surface in the resevoir and fluid gets sucked into the pump.

He's bled and flushed the system

 

Steering worked fine.

Replaced pump and flushed with power steering fluid - problems arose.

Swapped old (leaky) pump - problems still exist.

Flushed with ATF - problems still exist.

Bled the system over and over and over multiple ways so it's not that.

 

I have no idea what it could be or what to test, I'm equally at a loss given the rarity of Subaru rack failures.

 

Pretty sure i asked him and he said the fluid never really got low (which could ruin the rack I presume), but I should double check.

[WoodsWagon]

Seems odd to replace fairly expensive parts when the steering was working fine already? I don't usually replace pumps on a whim.

 

You can run racks without fluid and they will work fine, you will burn the pump up though.

 

He should check to see if he kinked a hard line when he pulled the pump. The ones that run from the pump across the head to the flex hoses could get bent if you tried removing the pump without unbolting the lines from the head.

[idosubaru]

your advice would send me right to the car, breaking something sounds like what i would do. LOL. i'll tell him to check those lines, he's fairly meticulous, much more so than i so i wouldn't expect him to bend/break stuff like me. but something is causing it.

 

Seems odd to replace fairly expensive parts

pumps can be had for $15.

 

when the steering was working fine already? I don't usually replace pumps on a whim.

eeerrrr, huh? did you see this yet, i'll quote again:

A friend had a leaking pump and replaced it.

the pump was leaking. dripping, loosing fluid, needing to be refilled = leaking. i talked to him ahead of time and he didn't feel like rebuilding it...sensible since used pumps are cheap anyway.

[johnceggleston]

any chance his front tire pressures are low??

 

any chance it could be the "car wash" effect, the car seems to run better after you fill it up with gas and run it through the car wash??

 

sounds like you need to take a road trip, georgia is nice this time of year.

[nipper]

1996 Impreza. A friend had a leaking pump and replaced it. Unknowingly he added power steering fluid instead of ATF to refill it. It had problems from the start and he finally saw that it was supposed to be ATF. He flushed and filled it but said the power steering is like %70 now and hasn't gotten any better over a few days. He even swapped in his old pump (since it worked fine) just to be sure that wasn't the cause, same symptoms.

 

He's bled and flushed the system and it's never taken me more than 30 seconds to bleed power steering lines so I dont' think that's it.

 

So the power steering fluid caused the rack to fail? Nothing to do except replace the rack then right?

 

ATF and PS fluid are interchangable except for cars with electric power steering (and i am sure someone will say i am wrong but tough nuggies).

 

My big question, why was the pump replaced if it worked fine?

 

What were the symptons to begin with (recovering from surgery so i am not reading the earlier responses).

 

Lets not replace anything till you fill me in on what is going on. How many miles on this?

 

nipper

[bheinen74]

or the ps fluid he dumped in there was what finally did in all the seals, o-rings etc due to not looking at the top of the cap that says what fluid to use.

 

I have seen certain rubbers (seals) totally swell using wrong fluids) or contaminated fluids

ruining what it contacts.

doesnt the rack have seals too?

[nipper]

So the steering is stiff? Thats not a usual failure mode. Also form what I can tell is that the porblem existed before the pump was changed? Its not the PS seals, if it was the rack would be leaking.

 

If the stering is stiff, inspect the Ball joints, Top hats, Tie rod ends. Racks when they go bad usually either leak or have no boost when cold.

 

I dont trust anyone who changes a pump just because.

[idosubaru]

My big question, why was the pump replaced if it worked fine?

For the 4th time: the pump was leaking so he replaced it.

 

No issues prior to replacing the pump. Replaced pump - issues. Installed old pump and the issue remains.

 

Roughly 150,000 miles.

 

I'll ask next I talk to him but I think the only symptom is it feels like it has %80 of the assist it used to have.

[nipper]

For the 4th time: the pump was leaking so he replaced it.

 

No issues prior to replacing the pump. Replaced pump - issues. Installed old pump and the issue remains.

 

Roughly 150,000 miles.

 

I'll ask next I talk to him but I think the only symptom is it feels like it has %80 of the assist it used to have.

 

 

For the 4th time on here i am in a fog.

 

Disconnect the rack and see if it binds anywhere while he turns the wheels. Ever think the "good pump" had crud in it and clogged the rack. Make sure the P/S hoses are good and have good flow. If he contaminated the rack with something fomr the 2nd pump, makes sense that the 1st pump wont work.

 

http://www.subaruforester.org/vbulletin/f89/power-steering-fluid-5209/

http://bbs.scoobynet.com/general-technical-10/806748-is-auto-transmission-fluid-the-same-as-power-steering-fluid.html

 

Usually the PS cap will say what fluid to use, and most Japanese cars use ATF fluid (again except electric boost). It is hard to say what is what when it is all over the phone. he also may have had other issues with the leaking pump that got worse when he restored the pump pressure.

 

If he is not interested in properly diagnosing things, heck, neither am I

[johnceggleston]

Racks rarely fail, and when they do, they leak.

 

Using the wrong fluid, PS vs ATF vs Engine oil won't hurt anything. Honda's are finicky about that, and subaru XT6's with the Cybrid steering are, but the rest have no issue with it.

 

 

don't ever put "brake fluid" in a 90 nissan hydraulic clutch system, you will ruin it and have to replace the slave cylinder.

[idosubaru]

right on nip, i understand, no offense meant. you'd be LOLing too, or worse, if you had to repeat yourself 4 times.

 

He's like one of my best friends, I talk to him all the time (poor fella, pray for him! ). He's quite adept at mechanics. The only symptom was leaking at the pump, no steering problems at all, we had been talking about it for awhile now prior to him trying to fix it. It immediately had noticeable symptoms right after installing the pump and filling it up. He assumed it needed bleeding and tried numerous times to bleed and flush it.

 

Disconnecting the rack - where do you mean?

[Tahoe Subaru]

try this it worked on my car. I don't know if this is your problem. but it was on mine.

 

http://allwheeldriveauto.com/why-is-the-power-steering-making-noise-on-my-subaru-outback/

[idosubaru]

That was a very interesting read, good stuff to know. He says it doesn't apply to the older models before 2000, but I'll definitely tell him to double check all the lines and fittings for tightness.

[Fairtax4me]

Not sure how to test that, probably a pressure gauge but i'm sure he's not interested in messing with that.

 

Take it off and blow through it? I've tested brake hoses that way before, not sure how well it would work in this case.

[Gloyale]

i talked to him ahead of time and he didn't feel like rebuilding it...sensible since used pumps are cheap anyway.

 

Yeah, but they can start leaking too.

 

Rebuild kits for these are like 30-40 bucks. I think it's the way better way to go. They are really easy to rebuild.

 

No real need for a press, you can drift the bearing and pump shaft out and in easy.