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Discussion Starter #1 (Edited)
Question for all you experts. Replaced my PS pump yesterday (new OEM) and after completion cannot seem to get to no air bubbles in the fluid.
I did the lock to lock thing for a very LONG time, including start and sit overnight and still had one or two small bubbles after each cycle, particularly when on the drivers side lock. I have no visible sources of leaks and I have checked and rechecked all connections. I replaced my suction hose last fall (new OEM)...but not the clamp. When the engine is running the pump is quiet and the fluid level is constant and there are zero bubbles present. Was thinking of replacing the suction hose clamps just for the heck of it but not even sure I should bother since the system is so quiet. Any thoughts?
 

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2005 Outback VDC limited 3.0r
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You have the engine off while bleeding the air correct? You need to have the front end up in the air and turn lock to lock.
 

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Discussion Starter #3
You have the engine off while bleeding the air correct? You need to have the front end up in the air and turn lock to lock.
Yes, engine off, front wheels off the ground. Stayed off the ground when I went to idle then shutdown and wait. Have since checked it at idle with weight on wheels and driven it
 

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2006 OutBean, 2005 LGTW
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Are you sure what you're seeing are bubbles and not fluid flow? It's hard to tell while you're at the steering wheel and easy to misinterpret fluid movement at the surface for a bubble.

I just did this job in the 09 and it was a PITA to get all the air out. I hacked a $10 home depot piss pot apart and used it to force fluid through the system which helped immensely.
 

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Discussion Starter #6
Yes, definitely a bubble. Has to be air in my opinion but I am not an expert hence my post :) . As I reach the stop at each side the fluid level rises slowly then an air bubble appears. The bubble occurs say 90% of the time on when the wheel is turned to the driver side lock. Must have something to do with the fluid return circuit I assume. When the car is at idle the fluid level is rock solid and there isn't even a hint of bubbling at all. Pump is super quiet. Last year I had to do the O-ring change so I know what it sounds like with an air leak. As a point of learning, if I do the pump every again I am going to add fluid to it first to minimize the air in the system at the beginning.

If it helps...I've only really been driving this car for about a year (wife's previously & I am a VW guy) so I have no feel for how the steering on this car is supposed to feel but the turning effort was (before new pump) and is (after new pump) a bit higher than my other cars (non-Subaru). Not sure if this is significant or not.

So aesthetic.rake explain to me the tool you cooked up? Curious as to how you created it and used it.
 

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2006 OutBean, 2005 LGTW
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My system was empty. I swapped out the suction hoses and pulled/flushed the reservoir so YMMV but, I took one of these:
Took the wand off, rigged up a section of hose to the trigger/handle then to the PS system of the car. I put the hose on the suction side of the steering rack, where the hard line comes up from the rack, goes to a soft line and into the reservoir.
I put a quart and a half, basically, all the Subaru ATF I had on hand, in the pressure pot, pumped it up, and forced ATF through the system until it filled up the reservoir. I had hoped I could force the fluid out of the other side of the reservoir but that didn't happen. In fact, the pressure pot tool took forever and considering I still had air on the other side of the reservoir, I question how effective it was.

That said, the fluid level rising past center point building up and peaking at full lock, in my experience, is normal. The system doesn't seem to flow very well when the car isn't running. My guess is there's a bunch of choke points in the system.

When working the wheel back and forth, it's important to take it slow. I don't think the FSM does very well at explaining that. If you work it lock to lock too fast, the fluid movement has a hard time keeping up and I think it works against your desired goal. It'll keep an air pocket in the rack and you'll just work it back and forth.

If you can start the car and turn the wheel without noise or shuttering, I'd say you're good. The test will be putting the system under load--the tires on the ground and driving the car around. If it doesn't make noise, you're good.

I trust you can tell the difference between fluid movement and a bubble but having just done this job I had a hard time telling from the drivers side of the car the difference between the two. Just like you I had the fluid level rise close to full lock but after I started the car, it didn't do that anymore. Once on the ground, the PS system made noise for a few days while it worked the rest of the air out of the system and now it's right as rain.
 

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Discussion Starter #8
Pretty ingenious pump idea. Surprised no one makes something specifically for this. With the right top you could maybe use a pressure bleeder type device.

Yes, its tricky to see the fluid from the drivers spot for sure. After doing it for like an hour I got good at it 😁
To your point, its quiet and everything seems normal so I'll just keep driving. I suppose since the cap doesn't feel air tight to me with continued driving any small bubbles will eventually get worked out.

Thanks for your help! Much appreciated
 

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Pretty ingenious pump idea. Surprised no one makes something specifically for this. With the right top you could maybe use a pressure bleeder type device.

Yes, its tricky to see the fluid from the drivers spot for sure. After doing it for like an hour I got good at it 😁
To your point, its quiet and everything seems normal so I'll just keep driving. I suppose since the cap doesn't feel air tight to me with continued driving any small bubbles will eventually get worked out.

Thanks for your help! Much appreciated
The problem with the bleeder that I built is I still have to disconnect it--which will introduce air into the system. It might have worked to force air out of the rack but ultimately, it introduces air into the system after it's pushed it all out. If that makes any sense.

The system is self bleeding so you'll have no problem working out whatever air is trapped. You'll hear groans occasionally but that'll be all. Good luck!
 

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05 GT wagon, 09 Spec B, 18 3.6R Outback
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Have you driven the car on figure 8's in a parking lot going lock to lock with the steering. That normally gets the air out. May take 3 or 4 times around.

If the steering is responsive and doesn't want to wander or feel disconnected ?
 

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Discussion Starter #11
It doesn't feel like there is any air left but I like that figure 8 idea. I'll give it a go.

Steering is responsive and taught. No wander. Feels like the effort has gone down just a bit too. Think I am good now.

Thanks everyone
 
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