Power Steering Pump Dying?

2014, 157K miles. Was having noises when cold with the power steering pump. Flushed fluid. It's still making noises and its possibly worse. Does this sound like a dying pump?

https://youtu.be/YCMW4lAye4U

What's strange is the rhythm of the noise. Turning the wheel does not change the sound either.

 

Definitely not the typical whining sound you get when the pump is failing, sounds more like a bearing noise from the pulley. Any play in the pulley?

 

that definitely doesn't sound like a normal p/s pump failure.. I'd pull the belt and check the idler pulleys

 

Tensioner pulley...swap with OEM and be good for another bit.. any reason to suspect the PS? Any leaks/weeping around pump or hose connection's? Sounds like the tensioner to me...

 

Might need your automotive stethoscope to find the offending bearing in this case. But as stated, doesn’t sound like a PS pump.

 

Main reason for suspecting it as to me, it sounds like it coming from that area, tends to improve a bit after warming up, fluid was really dirty. What isn't like that typical pumps I have seen is it isn't affected by turning the wheel-no louder, no softer.

Can I isolate a bad tensioner by just removing the belt and checking for play/noisy bearings?

 

The sound not oscillating while turning was the tell all for me...you certainly can isolate the sound...I've gone thru 3 aftermarket tensioners on warranty (1 year warranty) and finally just spent the additional $35 and got an OEM one...way better now. If you remove the belt you should be able to feel the pulley being ever so slightly being loose. You should be able to swap it out in like 15 min after you do it three times... that's all I know

 

Having a shop do it will be close to $150 to $200 which includes new belt and tensioner...

 

Well I located a stethascope and spent some time listening to all the pulleys, pumps, etc. I heard nothing too aggressive until I got to the alternator. Wow, when I touched the probed to the bracket and then the alternator body, it was like stepping inside of a jackhammer while it was being used to break concrete. It was 3X as loud as all other bearings and had the same rhythm as the noise heard on the outside.

I didn't know alternators could whine like a power steering pump until I saw a few examples online. Not sure it's just the alternator bearing or the whole thing is going.

 

Nice work! I forgot, this occasionally happens on the alternators! I'd swap the entire thing out or you could just replace the pulley, but I think it becomes a bear when doing it that way...

 

It's a bearing. The only other possibility is brushes, which would have to be completely used up, and the holders into the armature. Nothing else can be wrong with an alternator. That's why they're an easy rebuild if you want to mess with it. You'll need a press for the bearing, and you'll need to axially position the bearing properly for rotor location. Denso reman is probably the better choice.

 

That was going to be my next question-rebuild, new oem or aftermarket. Doesn't look very complex if I rebuild.

 

Owner rebuild possible if the damage is limited to the bearing, and you have no commutator damage. You'll want to replace the brushes while you're in there.

Once you have exposed the bearing, you can read the number off the bearing and buy a replacement from a bearing store using the same number. Stick with Japan or US manufacture. You will have to measure the bearing location on the rotor with a digital micrometer, and position the bearing properly when pressing it on.

Unless you just want to plumb the depth of your technical skills, buying a Denso reman alternator will likely be the better choice for most owners. Denso inspects all components before rebuilding with new bearings and brushes.

 

Thank you. I think I would like to by a reman. Denso and keep my core to learn on. I used to rebuild RC brushed motors-I know it's not even close-but something I would like to tinker with.

Do you have any recommendations for the best place to source a remanufactured Denso?