Power Steering Pump Bearing(s)
 

Driving the vert about four days ago when it started spitting Power Steering Pump bearing balls out of the nose of the pump.

Seems nobody sells PS Pumps anymore so I am doing a reman.

I ordered a rebuild kit online, but it comes without bearings.

Since the pump was shooting bearings, the bearing cover is gone so I can no longer see the bearing part number.

Does anyone know the part number/specs for the PS Pump bearing?

Also, although I have stripped the accessories off the PS pump, I have not yet cracked it open So I cannot yet see what is inside. I would think there is another bearing inside there. Does anyone know it's part number and spec?

Did a quick look on the parts fiche, looks like that part of the pump comes as a rebuild kit, similar to the "sealed" idler pulley, or throttle springs. Rare as a unicorn fart.

As far as determining bearing size and type, try to see if you can keep the races intact so you can measure them with a mic. Also check to see if you need a seal on the back side of the bearing, or if the bearing is lubricated by the pump. It probably isn't but if you can find a chunk of a seal, that would give you a better indication. Probably going to be a NACHI bearing of some kind.

Make sure to clean the races and shaft before you put the new one back in.

I'm pretty sure the identifying number will be on the outer race, not on the cover.

Rock Auto has an R&R service for the pump through Cardone, but you have to ship it to them to get an estimate.

Seeing as, it will cost at least $30 just to get the part to them and back and since there is not even an estimate of how much it will cost (at least as much as buying a reman of course, I decided to continue with taking the pump apart.

Does anyone here have any experience with doing an R&R on these pumps?

For now, I will continue to dismantle it in hops that someone will have had experience - either way, I need to go ahead and get the bad bearing out.

Well, I hope the number is on both sides of the race, because the exposed race is gone!

Lol! OK, I suppose I didn't quite understand the extent of the damage, whoops. I bet they use the same one front and back (cost effective), you'll have to take apart to see. They might not of but usually manufactures need to have a reason to increase cost. I'm also guessing there is two bearings because, it's kind of a standard thing. Could be wrong there also.

Actually on the inside, there is a shaft recess or "pit" with no bearing, but a bushing. (Edit 3: The shaft fits into the bushing and is a little loose, but still tight enough that I get a suction sound when I pull it back out. so I think that combined with a new bearing it should be OK) I cannot yet tell if it needs to come out (hope not). If I can get this further apart I should be able to tell if the end of the shaft fits snugly or not.

The pump is essentially a little rotary motor. The "leaves" you see in the pan fit into those slots of the central rotor and as the pump rotates, the leaves slide in and out tracing the shape of the rotor housing and pushing the oil around. (I may have already destroyed the pump by taking the leaves out and not knowing their orientation to go back - but they all fit back in easily.)

I have never seen a pump like this and have no idea how to proceed in taking it further apart without destroying or damaging it. I am searching the web for a clue.

If I had to guess, I would say that yanking on the shaft should pull the whole assembly apart, but so far something seems to be locking it in place.

Edit: I found NO vids on R&Ring this Mazda Pump, BUT, I did find this Ford vid...


And it looks the same as mine internally. And looking at the body, this seems to be exactly the same pump (core) as the 2001 Ford Escape. https://www.carid.com/cardone/power-...813&url=798553

Edit 2:

OK so I got brave and took the pump further apart. I turned it over to try to pry out the pump stator(?) and it just fell out. Leaving the shaft and bearing in place. But one slight tap from the hammer got the shaft out too.

Internally, these pumps are different (progress between 1988 and 2001?) but they are at least cousins. I would be willing to bet that if you can plumb them up, they would probably bolt right in.

The Aussie in the vid was very helpful in helping me see how to disassemble the actual pump, but I tend to think he is wrong about the placement of the vanes (leaves). He was saying that he placed the rounded edge of the vanes facing out from the shaft, but I would think that in 200K miles, the vanes would have been scraped flat by the wall (housing) of the pump. Any opinions?

So, back to the bearing... it is being held to the shaft by the pulley key which keeps it from moving forward.

Monday, I will take the shaft and the remnants of the bearing to the local bearing supplier to see if he can find a replacement for me. Or maybe I will stop by Northern Tools to get one of their digital calipers, I don't think mine with a millimeter scale (manually read) will be accurate enough...

Just convert using 25.4 to change mm's to inch, divide mm by 25.4 to get inch, multiply inch by 25.4 to get mm.

I'm sure it will be all metric.

I must be getting old,as I would not waste the "rest of my life"..heh,heh,rebuilding a damn PS pump!...I'd just post a WTB for a used one,Guys post up parts all the time.
I probably got a pump in my Shed.
uh,oh....heart Murmur....!!!..time to log out!

Yup, its a vane pump. Its a similar mechanism to an air impact (look up AVE videos on how these work). The rounded part of each vane goes to the inside. so that fluid can pressurize in between the vane and the shaft, pushing it out against the housing. This is what makes the vanes seal, otherwise the whole thing wouldn't ever build pressure.

As far as the bearing being stuck on the shaft, it had to go on one way or another. If the key comes out, that's the end it comes off of. If not, it comes off the other end. That bearing should be friction fit on the shaft anyway. Should be good and snug. If it stays stuck, use a torch and warm up the bearing race and try tapping it off with a plastic hammer or brass drift.

The bearing on my pump was NTN 6602LB. It was for a 1987 car.

Thanks for confirming the orientation of the vanes...

I wish I had read this before I decided to "get the bearing off"...

I had to lock the shaft into a vase (wrapped by cloth to protect as much as possible), and then use a hammer and screwdriver to get the half moon key canted. A couple of light taps, and then I was able to pull it out using a pair of surgical forceps.

And you are spot on about how tight the bearing was to the shaft. It was obviously pressed on and then locked behind the key, with a c-clip on the front to really lock it in.

I used a socket over the shaft to drift (hammer) it off the shaft. I can see that I left some minor(?) striations on the shaft, but I am thinking I can polish the shaft?

When I go to put a new bearing on I will heat the bearing in the oven first and freeze the shaft. A long time ago, I remember I was a able to just drop a bearing race into a brake rotor disc without any tools - it just dropped right in and seated itself, I am hoping the same will work for this so that I do not have to hammer the new bearing onto the shaft.

What do you think?

As for the bearing, if there were any markings on it, they are long gone, so I have absolutely no idea what I am looking for.

All I know is is't measurements...

11mm Thick
35mm OD
15mm ID
14 balls (looks like).

While I understand what you are saying...

My Vert now has a rebuilt engine and everything else on it seems to be working smoothly - except the oil pressure sender - I don't know why every Mazda I have ever had has problems with these. Condition wise, it looks new to most people who don't know what it is. They are shocked when I tell them it is 30 years old. I do want to replace the wheel bearing next - it sat on them for too long.

Finding out that the PS pump is not available anywhere (rebuilt) was a little bit of a shock.

Yes, I could buy a used one from someone, but what condition will it be in? Maybe just another couple thousand miles before that replacement goes bad?

If I am going to keep my car - as I plan to, with more and more parts being almost impossible to find, I think it will behoove me to learn to disassemble and rebuild these parts myself. I think it is even better to learn this while there is still the possibility that a replacement can still be found used in case I really screw up something.

(I did find someone on E-Bay who says he has a reman for sale. But even though he has a fairly good rep, I am holding my breath hoping he will not come back and say he doesn't have the pumps he said he did. Some of his negative rep says he does have a habit of claiming a part and then not actually having it.)

A pump like this with a $20 seal kit and possibly a $30 bearing seems a good candidate to me to DYI. Besides, I am retired, I have the time.

Tremendous thanks.

Mine is an 88, but I am hoping these are the same bearings, I will look them up.

Again, I appreciate the input.

Based on your input and the measurements I took, I am guessing I can use this bearing...

https://www.grainger.com/product/NTN...-Bearing-6L024

Does anyone know if there is a "hardiness" grade I need to look out for?

Edit:

I found several candidate bearings on Grainer Site.

https://www.grainger.com/product/com...C1L015%2C1ZGH2

One is rated at 17,000 rpm, another is rated at 28,000 rpm. I will go with the higher speed bearing.

Edit:

At first glance it seems the higher speed bearing would be the logical choice... But since this new bearing will only have to rotate at about 500 rpm, I wonder if I am sacrificing anything when choosing the higher speed bearing. It is also rated for a higher power, so I am thinking it is still the right one to get.

I'm retired too so therefore I do things quickly and "efficiently" as I am not exactly sure if I'll have time to actually enjoy it..

IF I have a Pump,would you take it,for say 5 Bucks and the price of shipping?..I am downsizing since I am now living Solo..so anything I do not need is either getting tossed or sold,cheaply!

LMK,as I am gonna go Full blown spastic on my shed..!

Sure, why not. As I said, I don't know yet if I am going to receive the rebuilt. And that will let me continue with this one with less fear of damaging it.

Here is a company selling the PS Pump bearing for about $1.50.

https://www.primebearing.com/6202-2R...-15X35X11.html

They are also selling the larger idler.

6203-2RS, 6203 2RS sealed radial ball bearings 17x40x12

I went through this same exercise earlier this year. The PS original PS pump on my 90 GXL just locked-up on morning. Just like you, I wasn't able to find a rebuilt pump anywhere. I eventually bought a used pump from a bone yard in SoCal.

BTW, Summit sells PS pumps for the RX7 and they do have one in stock. Not sure if it's an engine speed sensing pump or vehicle speed sensing pump. The other pumps are on back order until beginning Aug. Hope this helps.

Thanks for the feedback... I am waiting to hear details on one reman from ebay, one used from this site, and the parts for my rebuild. If none of these things work out, I will check Summit.

My primary hope is that I will get mine back together successfully and to have learned a new skill!

As far as your work in progress pump goes, when you inspect the shaft, you want to make sure it is completely smooth. Any burrs that you can catch with your fingernail are going to give you fits. I would use a fine sharpening stone and some light oil, like Remoil or 3-in-1 to knock off the burrs that you made, then handle it gently. You will just be working on the burrs. Don't want to take any material out of the shaft diameter. As far as differential heating is concerned, wrap the shaft in a dry towel and place it in the deep freeze. You may not need to heat the bearing, if its a hot summer day, and you have a sub-zero shaft temp, should slide or tap right on. Just make sure you have all the burrs cleaned up. I'd use a brass drift on the inner race to install the bearing unless you have a better socket. Problem I have had using sockets is that I often damage the seal and make the bearing have a snag in a normally smooth motion. If you use one for installation, make sure it seats good against the inner race without galling the shaft.

f you have a lathe, you can turn and bore your own installation socket that would only contact the inner race. That works swell. Not everybody has a lathe, but it is a suggestion.

Do that and it should slide right on. On the same token, once you're done, you can freeze the shaft and bearing for installation in the housing.

Bearing races should all be made of about the same material. The difference in ball bearing speeds ratings is usually how they are lubricated kept cool.

Good luck, let us know how it goes

Thanks for the tips.

So far, I am still waiting for the seal kit from CardID. I am going to have to call them to cancel and order from someone else.

In the mean time, an Ebay seller said they had 8 re-manufactured units on hand so I ordered one from BUYAUTOPARTS.COM.

What they sent me doesn't fit. It seems to be the same pump, - but with a different shaft - most likely this is the unit for the Ford I mentioned above.

So far I have been waiting 20 minutes on the phone for someone to take my call... One person answered, but as soon as I said they sold me the wrong part, he put me back into the phone queue (this is probably a "we never plan to answer queue").

Anyway, the pump is actually so close that I will try to figure out if I can use it. The only difference see so far is that this "wrong" pump has a geared central shaft - while mine is smooth.

Does anyone here have a pump that also has a splined shaft? (The splined is where the pulley attaches).

That stinks. Do you have any pictures?

OK, BUYAUTOPARTS lists a Mazda RX7 PS Pump as A1-Cardone Part number 21-5814. This is WRONG. That part is for a 90-95 Mazda MPV.

It has a splined shaft.

I called Cardone and the proper part number is 21-5846. This is not available anywhere in the country as far as I can tell.

The attached pic shows the wrong part (splined shaft) and the Mazda RX7 Pulley (Keyed.)

I searched for and found the MPV pulley - it is serpentine and therefore of no use.

You know, I wonder if I were to take the pulley hub to a machinist and have him insert a plug into the bore hole and keyway, and then cut splines into it?

Is the diameter the right size? If it is, it might work anyways. If the fit is good on the diameter, the grooves won't really matter.

Diameter is good, but now way to lock the pulley with the keyway.

Ahhh, no key way, my bad.

I edited to say a keyway is most likely cheaper than splines. Splines are very expensive..

Agreed. Which is why I find it interesting that newer pumps are splined when the don't really need to be. A key would do just as well.

Anyway.

I just spoke to a sales engineer at a gear company. (I was looking for a inside geared collar that could go over the splined shaft, and fit inside the pulley hub.

The salesman suggest that instead, I just look for an oilite (soft bronze) collar that will fit inside the pulley and can be pressed over the splines. The splines would cut into the bronze and make a locked fit.

Unfortunately, it might take a couple tries to find the right thickness bushing and in the meantime the shaft might be damaged. But it is still anther option of all others fail.

The problem with pressing that bushing on like that is the difficulty in getting the pulley to run truly perpendicular with the shaft. Might get a case of the wobbles, then your bearing and seals get worn out too quickly. Plus then you would still have to have a keyway cut through the brass and the steel shaft. Might cost you more than it's worth

Just had a thought. After replacing any o-rings and such, you could lap the mating surfaces of your old pump housing and then potentially seal it with a type-2 sealer or equivalent anaerobic. Then you wouldn't necessarily need the gasket set. Don't know if that helps

Yea, I thought of that one too.

My goal right now if I have to machine is to make no changes to the pump at all, but to the pulley hub.

I am currently taking a mold of the space between the shaft and the pulley to take to a local machine shop to see what can or can't be done on a press.

It's funny, other than the fact that I am not able to drive my car, I am enjoying this research and fab project.

You know if lead (or something not toxic dried/cooled to something that could provide just enough grip on the splined shaft without being deformed by the heat/torque, it would be easy to loosely mate the hub to the shaft - and then pour in that filer material.

If the pulley hole is larger than the shaft diameter, have bushing machined that you can cut a keyway in. No need for a pour or lead. Measure shaft, measure hole, you're done (let the machinist do this, he will be able to precision measure the stuff).

Also, look close at this key. If it's a Woodruff key, there doesn't need to be a full length slot (if there is one now). This key could be used instead of a standard straight key if that is what's in there now. A machinist will know where you're going with this if you talk to him. A Woodruff key won't cut your newly machined bushing in half. I'd try to make the keyseat deep enough to hit the old keymay, locking it all together. A good machinist should not have a problem getting the whole shebang done right.

Might cost a bit though unless you know someone.

I think they might have gone to the splines because of the weight of the vehicle it was put in. Even if they didn't up the pressure of the pump, I bet the heavy MPV puts a greater load on the pump to just turn the wheels as compared to the light front end of the RX7. In fact, after thinking more on it, the only thing different might be the pressure relief valve. That might be something to think about.

OK, I have received my rebuild kit, so I am going to document the process.

1. Cleaning the inside of the housing.
   1. While cleaning the housing I noticed small bits of something. Not sure if it was rubber, metal, or whatever, but I cleaned them out.
   2. I also sprayed the inside of the housing with a little brake cleaner.
   3. Wiped the whole thing down.
   
   
2. I drifted the new bearing to the shaft.
   
   1. I put the shaft into the freezer overnight.
   2. I heated the bearing to 175 in a toaster oven.
   3. This only got the bearing so far onto the shaft, so I used a socket the size of the inner race of the bearing and a hammer to get the bearing seated.
   4. Unfortunately I was not careful enough to choose a long enough socket and put a few burrs into the end of the shaft before the nut threads.
3. I removed all striations and burrs from the shaft.
   
   1. I inserted the non-bearing end of the shaft into the chuck of my drill press. (hand tightened only with paper around the shaft to protect it.)
   2. I then stapled a strip of emery cloth to a 1"x 3/4" x 5" block of wood.
   3. I set the press to low speed.
   4. I squirted a bit of oil onto the strip of emery cloth.
   5. As the shaft turned in the press, I lightly pressed the block of wood to the shaft until all burrs were removed and the pulley hub could easily go over the shaft again.
4. I fitted the new rubber seal into the pump housing
   
   1. This time I was more careful about the size sockets I selected and the seal went in without damaging anything else.
5. Getting the shaft and bearing into the housing
   1. Trying heat differential again, I am heating the pump body up to 200 degrees.
   2. The shaft - with the bearing attached is back in the freezer.
   3. I will try to get them to mate. Again, I have chosen a good size socket in case drifting will be needed.
   4. Note: At this differential, the bearing dropped right into the housing, no hammering needed. If I were to do it again, I would try at 190 degrees because I don't know how much heat the rubber seal can handle.
6. Letting the housing cool down
   
7. Inserted a new o-ring seal into the housing
   1. Removed the old outer o-ring. It was rather hard and flattened to the side next to the housing.
   At this point I want to note that I purchased EDELMANN 8831 PS Rebuild Kit. It has a lot of little parts that are not for my pump. In addition it is missing the 14mm (ID), 18mm (OD) O-Ring needed for under the "Side Plate" (O-Ring" Inner) The only other O-rings in the kit are either too big or too small. I've gone to Northern Tool to get a variety pack of rings. My recommendation: if you can find the seal (Part number #AEO-816G) and the Case Gasket independently, you are probably better off just buying them and getting the other parts separably.
8. Letting the housing cool down
   
9. Closing the pump.
   1. Inserted all the o-rings.
   2. Inserted the main spring.
   3. Inserted the plates.
   4. Inserted the rotor and all the vanes (flat side out).
   5. Inserted the cam ring.
   6. New gasket on and bolts in.

I have a few concerns, for those of you who know vane pumps... I guess I will find out if I did OK tomorrow when I run it.

1. When I took it apart and was turning the rotor, I could see the vanes moving in and out. I don't see it doing that anymore. I am hoping that is because it is not as highly lubricated as when it first came apart and the movement I saw was due to gravity? Does centripetal force alone drive the vanes?
2. The case was pretty far apart when I first started tightening the bolts (seemed to be about 3 or 4 mm, but as I tightened the bolts, the gap closed easily and without needing force.
3. The shaft is just about as hard to turn as the shaft on the professionally rebuilt pump I have, but I attribute that to the fact there is no lube in there. Maybe I should actually pour some ATF into one of the ports before I put the accessories back onto the pump tomorrow.

Congrats and I am hoping for complete success. I don't think you hurt anything at 200 degrees. I guess I misunderstood your problem when I made my last post.

All input is welcome.

*#%y(*&y#$* i can't believe this...
 

WTF...

I get the pump together, put all the accessories back on. Install it back into the car... And then when putting the Power Solenoid back onto the pump I snapped the threaded head off the solenoid!

I can't believe this crap! I thought I was being careful, but the solenoid takes a 17mm wrench and what seemed to be the slightest tightening and it's gone!

Now I have to try to find a solenoid.

Apparently these threads are not part of the body, but brazed on?I may try some of that Devcon Weldit.


EDIT:

Looks like I am not missing anything with the Solenoid not attached... I put it on my bench tester and unless it is not the simple positive/negative voltage it appears to be (two wires) is does not do anything any way. Tomorrow I will buy a bolt to put in it's place and see how the car drives.

hey bud,

you may want to look at the FSM on that solenoid. Its a control item. Check out the section on fuel and emissions for your car. It got lumped in with all the sensors at the end of that section. Probably want to take a look. You can probably see if one of these guys with a junked pump can send one to you for $20 or so...

A M14x1.5 Oil Drain Plug Fits perfectly.

The piece the threads broke off of looks like a cap of some sort. Do you think you can get it off? Maybe you could tap it M14 X 1.5, get a smallpiece of metric threaded rod from McMaster, drill a hole in it, cut it to proper length, and now you're done (maybe a little loctite on the solenoid side).

Be very careful (which I think you will be) messing with the "cap", do everything possible to see if there is a spring under it. I don't want you unscrewing it and then boing! Parts go flying (been there before).

Yeah, seeing the o-ring that makes the seal, probably pretty low torque.

I believe you are right, that it is a cap... I was going to (I still might) put it in my vise and torque the head off to see what is inside, but with the oil drain plug I put in place, I don't think I need it (although I would like to keep the car as original as possible.)

The car drives just as it did before. I get the feeling that over the 30 years I have owned the car, the Speed Adjusting feature of the PS failed and I didn't notice. And as I said, that module does nothing now and is not really needed.

For now, I will see how long this rebuilt pump lasts while I continue my search for another to rebuild (to have as a spare).

I am not sure yet if I did a good job rebuilding - but it did survive it startup and a 25 mile trip today. It pumps and so far it doesn't leak. The only thing I don't like is that there seems to be a rubbing noise coming from the rubber seal under the new bearing (I didn't lube it when I put it in, I would have thought that the PS fluid would lubricate it... Guess I may have been wrong about that, but I am learning).

I really feel that any maintenance I need to do in the future will require that I rebuild more parts myself; so this has been a good experience.