Hello, I’d like to replace the shaft seal and bearings, and I suppose the backplate O-ring on my pool pump and motor. Its started to leak, and on very rare occasion squeal. I want to make sure I order the right parts, which is what I need help with. 
I’ve attached photos of my motor and pump tags. Thank you!
Sorry for the delayed response. Both of us who work on the forum were on vacation last week.
Your motor would require two 6203 bearings. Click Here to View the Motor Bearings
The shaft seal is part number R0445500.Click Here to View the Shaft Seal
The backplate o-ring is part number 5020-136.Click Here to View the Backplate O-ring
No worries. Thanks for the responce. I saw another post on the forum where someone had the same motor as me and he said that he eneded up needing 1) 6203DW (rear) and 1) 6304DU (front). You guys noted that it might have been a one off year or something. I don’t want to leave my pool without circulation for more than a day or two while I rebuild the motor. How can I be sure I do not need to above mentioned bearings, without taking the motor apart and seeing them? Might not be possible I suppose.
I’ll forward your motor label picture to our Century motor rep and see if he can confirm the bearings based on the serial number.
1 Like
The first rep I contacted must have just retired or stopped working for Century. My email bounced back. I’m reaching out to another territory rep. Sorry for the delay.
If you are in a rush, I would suggest getting two 6203 bearings and one 6304 bearing. That way you’ll have what you need either way.
1 Like
Thanks, I did just that yesterday. I’ll return whichever bearing it turns out I don’t need. Thank you for the help. I’ll post which ones end up being the right combo.
1 Like
I pulled the motor off the pump and got to work. It did take the 1) 6203DW (rear) and 1) 6304DU (front) bearing combo. After putting everything back togethar, the motor is making a high pitched noise while running, and it has a small leak from the shaft. I’m going to have to pull it apart again and see if I did something wrong. Is there a diagram of the shaft seal assembly somewhere I could reference? I put it back in the same way the old one came out, but I’m guessing I didn’t do something right. Thank you.
We have a blog and video on this topic. Here is a link. https://www.inyopools.com/Blog/psc-ep-58-correct-orientation-shaft-seal/
I pulled it apart and put it back togethar again and its still making the noise and leaking a little bit out of the bottom. I’m looking at pictures of the impeller on the parts diagram and I think the impeller I have may have remnents of the rubber part of the old shaft seal still on the plastic surface of the impeller that it butts up against. I thought that that was some type of seat for the shaft seal that was a little warn down, but I’m second guessing that now. The pictures of new ones look like a smooth surface. Wish I’d taken a picture of that. Maybe I’ll pull it apart again tomorow if I have time and take a pic.
It is most likely part of the old shaft seal. If you post a picture, we can try and determine that.
I pulled the motor off again and took a look at the impeller. I’ve attached some photos here. The part of the empeller that the shaft seal sits on seems to be warn down and now it has a groove that the shaft seal sits in place on. So I don’t think that its part of the old seal. On the outter part of the impeller, where it spins inside of, the edge looks pretty warn down also. Could these issues cause the leaking and squealing sound? Thanks again for the support.
It does look like the impeller is worn down around the edge and on the shaft. It could be rubbing against the diffuser but that would be more of a grinding sound. It’s possible that because the shaft is worn and the seal is slightly off that it could leak between the motor and seal plate.
Pictured below is a new impeller. You can see that that the end of the impeller shaft is flat.
Okay. I’ve ordered a new impeller and diffuser which I obviously need regardless. Hopefully that fixes the issues.
1 Like
That should fix the problem. If not, the only other possibility would be a damaged seal plate where the shaft seal sits. However, that is rare.
1 Like
So since I already have the impeller off, I thought I fire up the motor without anything attached to see what it sounded like. The whining noise is coming from the motor. I took the back plate off and ran it like that to see if that made a difference and its the same. Is one of my new bearings noisy, or did I do something wrong?
It sounds like the bearings. The bearing(s) could have been damaged when being pressed onto the shaft. We see it often when the bearing has a flat spot on the outside caused by a hammer.
Welp, I replaced the bearings (again) and installed the new impeller and diffuser. I had to also order a die to fix the threads on the motor shaft. I got everything put back together again yesterday and now she’s purring like a kitten with no leaks. Thank you very much for all the help and support. I really appreciate it.
1 Like
That’s great to hear. Thank you for the update!