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Post is about exactly what it says. I'll be outlining how to clean out the dc motor side of the power steering motor.

Why: overtime, the commutator and brushes in the motor wear down and burnt up copper starts coating everything. Kind of like what happens in the bell housing as the clutch wears out. This powder causes higher heat retention and increased resistance in the motor. Eventually, the motor either gets so hot or is pulling so much power that the ecu refuses to turn it on and you get the P/S light, code 21, 22, or 23, and the power steering stops working. However, the scope of this post is not to diagnose your power steering issue, it is to resolve what is sometimes a cause of one.

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First, empty the resevoir with a turkey baster or something. There is a lot more in there than you think. Remove as much as possible to make your life easier.

2nd, undo the 3 electrical connections. You just squeeze em and tap them ofd with a screw driver from above if they are tight. Easy. When putting back together use some dielectric grease on the terminals if that's your speed.

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I know the above pic is already out of the car but its a good view that you dont have while it is in. Maybe this will help you.

3rd, Undo the high pressure refill line. Its just a metal clip and a pressure fit. Pull off the tube. Then, unscrew the high pressure output line (the metal one that is screwed in, pictured below bottom right. i dont know the size, i just used a spanner. stufd will leak out so have some rags handy.
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4th: look back at the first above view image. See the 3 attachment points? They are all 12mm. I used a ratchet with an extension to remove each one. One of them is a nut on a stud while the other 2 are bolts. When moving the nut, pickuo the washer under it too. If you forget to, when you pull the pump you may lose the washer and then you wont compress the bushing right on reinstallation. At this point, the pump should be free. Take it out and lets continue.

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See this black cylinder in the image above? That's what we are removing. 3 small bolts and its off. If there isn't hot glue on one of the bolts, its prob been opened before. Nothing with this systwm is torqued to tight so should be easy. When the bolts are off, you may feel the cylinder is stuck. It isn't. There are strong magnets holding it un place. Just hold the cast base of the pump with one hand and pull really hard with the other. There is a circular waffle spring thingy that may fall out. DO NOT LOSE IT. If you don't see it, look into the cylinder you just pulled off. It should be sitting in an indentation at the end. If it isn't, but is instead sticking to a magnet, we're gonna have a little fun later.

For this next part, I highly suggest you wear an N95 or greater mask and safety glasses. Do what you will but just understand that metals and your lungs are like that catholic school dance. Leave room for the holy spirit or you're gonna get beat. You've been warned.

I have a video of me doing this next part but I don't feel like figuring out how to post it. Just take a compressed air can or use an air comoressor and blow out the motor assembly and cap (black cylinder). Dust will fly everywhere. This is burnt up copper among other things. I suggest you do this outside in a well ventilated area. Blow out the wire loom. Most importantly though, blow out the base where the spindle meets the rest of the motor/pump. This is where the commutator and brushes are located. Get all the dust out. Make suree all the spings down there are in place.
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Now, let ready for reassembly! Put a light coat of grease on the bearing at the end of the spindle. Its the one you can easily access so dont think too hard. I used some random black synthetic shit i had laying around in a jar. When i say light, i mean barely any than wipe off. Should see any but there should be residue. Now, find that waffle spring if it isnt already in its home. If it is out of place, take a dab of silicone black rtv and smoosh it back into its home. Kind of challenging if you have swole rock climber hands like me that dont fit into tight places. Now, either let it cure and put the cylinder cap back on tomorrow, or use some finesse.
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See the circular indentation at the bottom? That's where the circle waffle spring thing goes. You have to gook it in place or it will fly out of place as you put the cylinder back on over the rest of the assembly. I didnt wait and i put it back together by very firmly holding the motor with one hand and very firmly maintainung control of the cap with the magnets as i slid it over. If you bump it, the spring will come out of place and you have to start over. Also, before i reassembled, i greased and cleaned the ring gasket and i sanded and cleaned the mating surfaces. I also sprayed out the magnets with electronic cleaner and let it flash off. Also, i'm not sure, but mark which holes go where before disassembly because the cap might only go back on one way.

Torque the bolts back on in a triangle pattern (lol) and use loctite. They werent tight when i took em off so i didnt go wild putting em back on.

Go back to your car and reassemble. Leave the pressurized return line off. Its the one that is held on with a clip and is rubber. Not the metal hose. Shove a bleeder line into the house and put the clip over. Make sure its tight or it will blowout. My bleeder pvc tube was too small so i used teflon i had laying around to make it fat and tight. Do this or you will be sad when fluid goes everywhere.
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Now, using your fluid of cjoice, fill up the resevoir to the cold max line. Im not here to debagte fluids, you can research that. I used pentosin chf11s but most people are now reccomending nissan hydro electric power steering fluid. Theres a whole thread where a bunch of sampleas of diff fluids were sent to blackstone so read to your hearts content. Also, dont believe any fluid reccs from the dealer. The parts dep i talked to refused to ak owledge that toyora ever used different power steering fluid and refused to look it up under the mr2 in the system, basically callung me misinformed and telling me to pound sand. I was very polite too smh. Anyways, figure out what fluix you want to use. Napa had the pentosin in stock so i used it. 28 for a liter. Dont spill any fool.

Plug the plastic stem the return line goes on before filling the fluid btw. Put the bleeder line into a bucket to catch the gook. Jack the front wheels of the cae off the ground. I put the fronr on stands and chocked the back wheels+ parking break. Make sure the wheels can spin freely without touching the ground.

Now, I want you to stand out of your car, staring at the resevoir, while starting the car. In a few second, the resevoir will drop. Stop the car, top it off, repear. DO NOT let it suck air unless you want to buy more fluid. Now, with the car off, do the same thing while turning the wheel all the way back in forth a few times. Make sure to continually top off the fluid to the cold max line.

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When all the fluid coming out is new fluid and youve purged the air and dont feel like doing anymore cus you ran ojt of fluid, make sure that the fluid is filled to the halfway between cold mind and max. Baste out extra is needed. Put the return line back on the plastic stem and clean up. You are done. Put the car back on the ground and test drive, stopping to check for leaks. If the steering feel is soft or inconsistent or doesnt track right, you have air in the lines. Repeat steps with fresh fluid, making sure to not let the resevoir run dry.

If you couldn't bleed the system, aka the pump didnt turn on, something else is wrong. Good luck. Forgive the spelling issues and dropped letters.i ttped this up on mobile.
 

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Excellent write up, thank you. I never thought about taking it apart, just considered flushing it. Too bad one could not have a way to accurately assess the (dis)advantage of dissembling versus flushing. Flushing is less disruptive but perhaps uses more fluid.

A word to the wise, the o-ring gasket might best be greased by a neutral non-interactive grease such as silicone. I would imagine the seal is probably Nitrile which is resistant to oils and petroleum, unless you can tell, the risk of compromising the seal isn’t worth it.
Related to the fluid, yes read the SC write up on it, or simply choose Ravenol EP-SF or Nissan Electro PSF. Being cavalier on this could be catastrophic in the long run.
 

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Excellent write up, thank you. I never thought about taking it apart, just considered flushing it. Too bad one could not have a way to accurately assess the (dis)advantage of dissembling versus flushing. Flushing is less disruptive but perhaps uses more fluid.

A word to the wise, the o-ring gasket might best be greased by a neutral non-interactive grease such as silicone. I would imagine the seal is probably Nitrile which is resistant to oils and petroleum, unless you can tell, the risk of compromising the seal isn’t worth it.
Related to the fluid, yes read the SC write up on it, or simply choose Ravenol EP-SF or Nissan Electro PSF. Being cavalier on this could be catastrophic in the long run.
Thanks for the note on using silicone on o rings. Didn't think about that and will definitely do that going forward! As for the difference between flushing and dissassembly, they both clean two seperate areas. They are in no way interchangeable. The power steering pump is a hydraulic pump driven by a dc motor. The dc motor side is sealed from the hydraulic pump side. The spindle aka shaft of the motor passes into the hydraulic side and works some sort of mechanism. There was no hydraulic fluid in the motor side I took apart. Therefore, flushing will only serve to ungook the hydraulic side and the lines plus whatever the mechanism on the rack is. Maybe I'm completely wrong but just my 2 cents. Both do their job but they seevice different aspects of the system.
 

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Yes. Wow that was a stupid thought process on my part. I should have thought that through a little. Flush versus motor epiphany occurred to me as I was thinking about the needed maintenance. I should have stopped and actually considered what I was typing. Ouch.
 

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Yes. Wow that was a stupid thought process on my part. I should have thought that through a little. Flush versus motor epiphany occurred to me as I was thinking about the needed maintenance. I should have stopped and actually considered what I was typing. Ouch.
Haha. Honestly, until i cracked this thing open, I wasn't too sure myself. I covered ny work bench in old wall street journals i had laying around just in case i was wrong and fluid spilled everyhere haha so I was right there with you.
 

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Yes. Wow that was a stupid thought process on my part. I should have thought that through a little. Flush versus motor epiphany occurred to me as I was thinking about the needed maintenance. I should have stopped and actually considered what I was typing. Ouch.
Hwres a good picture of the contact surfaces i was focusing on cleaning with my compressed air. https://www.quantumdev.com/wp
 
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