I recently replaced all the low pressure rubber return lines on my Nissan's power steering system. They specify Dexron for the PS system, so I refilled the system using Mobil D/M and bleed according to the procedure in the FSM. As I bleed the system I continue to monitor the reservoir for bubbles, but I cannot seem to get rid of these tiny "soda" like bubbles. The pump is not making any noise and the power steering seems to be working fine. I let the car sit overnight, in the morning the reservoir showed no signs of bubbles, but after starting the engine and running for a minute, the soda-like bubbles reappear. It's the same consistent amount of bubbles no longer how long I let it run for. While some bubbles recycle back down the supply/suction line, a fraction of them rise to the surface and go away, which makes me think there is air being constantly sucked in somewhere?
Not sure if this is normal(never really paid attention to it in the past) or could it be a o-ring the pump's suction inlet? The reservoir is higher than the pump and is fed down via a 5/8" hose which is brand new as well. No fluid leaks anywhere on the PS system.
I recently replaced the PS reservoir in my Challenger and did a fluid flush and fill at the same time, and while I was flushing the old fluid (and turning the wheel back and forth w/ engine running), I managed to let the pump run dry for an instant. No damage or anything, but that did require much more labor afterward turning the wheel and filling the reservoir with fresh fluid in order to flush out all the air it accidentally ingested.
I bring that up because the bubbling I saw in my reservoir look just like the ones in the fluid in the video you have in your post. I can't speak to whether or not simply having air in your PS system is the culprit here (and thus would only require much effort to bleed it completely out), or if there is something wrong somewhere causing the bubbles. But I'm telling you, that's a spitting image of what mine looked like while I bled the system.
So I am thinking that it couldn't hurt to assume it's just air in the system and see if you can bleed it out by the old stand-by method (get wheels off the ground, then turn the wheels lock-to-lock over and over with engine off until no more bubbles). If you to that for a while and it does not help, well then nothing is lost and you're back in the same spot where you started.
But if it does do the trick, you just made your own day!
After I started hearing horrible screeching sounds coming from my power steering, I thought it was the belt and I replaced all the drive belts. That didn't solve the problem. It turned out that the fluid level was too low. I added fluid and then turned the steering wheel from lock to lock multiple times to bleed the system but the bubbles never fully disappeared. It's probably a small leak and/or pump problems. I won't bother repairing it unless it becomes problematic.
This said, looking at your video, your problem is a lot worse than mine. It's definitely sucking in air like crazy from somewhere and there may be a large fluid leak as well. In my case I can only see a few tiny bubbles after I turn the steering wheel from lock to lock a few times.
1985 Toyota Corolla LE, 4A-LC engine, ~ 271,000 M Toyota (TGMO) 0W-20 SN high-moly GTL (new formulation) Mobil 1 EP M1-103 filter, 90430-12031 drain gasket
Make yourself one of these, a mity vac, a rubber stopper from the hardware store big enough to cover the fill hole and a stiff piece 1/4" plastic tubing. GM actually has a special tools part# for this. Drill a hole slightly smaller than the tubing, slash cut the end of the tubing making it easier to get through the rubber and use wd40.
Pull 15in vacuum and watch the gauge, if may drop a few time as it pulls the air out of the system but at some point it should hold a vacuum not going down more than a few in over 53-4 min. Once it does that leave it under vacuum for an hour or so, it will draw the air bubbles out of the system, check it didn't loose vacuum as it will go down when the air comes out.
Replaced the inlet o-ring and it made no difference. The vacuum pump is a good idea, I will give it a try this week. That should rule out any air leaks on the suction side for sure. Thanks everyone! Will report back.