Slow motor startup

New2water

LifeTime Supporter
Jun 28, 2011
78
Stockton, CA
The motor for my pool filter pump motor (plate picture attached) has recently become slow to start. I swapped the capacitor from a different pump (condition unknown) without any change in results. It is a single 50uF capacitor and I'm not sure if it is for starting or running the motor. Once the motor picks up speed in less than 5 seconds, it runs fine.
Show I purchase a new capacitor or look for the problem someplace else?
 

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borjis

LifeTime Supporter
Aug 19, 2014
3,317
Pacific NW
take out the pump basket with the power off (turn off circuit breaker too) and see if you can
feel for debris or spin the pump free and easily.

how did the electric connections area look? all shiny/new or corroded?
 

JamesW

TFP Expert
Mar 2, 2011
21,076
I think that that motor usually takes a 30 uF capacitor. What was the uF of the original capacitor? Try a new one with the correct uF rating.

First verify that the shaft turns smoothly and easily. You can access the shaft from the back by removing the small round cover in the back center of the motor. You will need to pry it off with a small flat screwdriver. Then, you can turn the shaft with a 1/2" open end wrench.
 

New2water

LifeTime Supporter
Jun 28, 2011
78
Stockton, CA
Thank you for for your quick responses and guidance. This gives me a course of actions; checking the shaft for free spin, electrical contacts for rust, and the capacitor using AVO meter. Both my capacitors are 50 uF. Will report back tomorrow.
 

New2water

LifeTime Supporter
Jun 28, 2011
78
Stockton, CA
My apologies for late reply. Had to go out of town for a few days.
The capacitor checked out good so did the shaft free spin. The only thing I found was loose capacitor connectors. I've tightened them and it seems to be working fine.
Thank you for the help.
 

New2water

LifeTime Supporter
Jun 28, 2011
78
Stockton, CA
I was mistaken. The shaft turned with the help of a wrench or plier but not freely by hand. I'm ready to replace the bearings and want to be sure I am buying the correct replacement parts. I've found the manual for my pump here and the motor here. The motor and pump plates are attached.
I've read that there are different seals used by the manufacturer so I'm wondering how to figure out the correct part number. Secondly, Do I have to purchase bearings sold by the motor manufacturer or any Timkin bearing of that size? My understanding is that bearings are not manufactured by the motor manufacturer and 203FF bearings meet the same specs irrespective of the manufacturer. Am I misinformed?
Recommended sources for these parts are appreciated.
 

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New2water

LifeTime Supporter
Jun 28, 2011
78
Stockton, CA
Update:
With a little bit of effort, I was able to contact the manufacturers of the pump and the motor. They were very helpful and provided the information below.
Pentair (919)566-8000
Pump model WFE-4
Shaft seal part # 0717345 (PS1000)
Seal plate gaskit # 357100
Diffuser O Ring # 355227
Motor # 3550105
The pump manual is here.

Century Centurion A.O. Smith Motors (800)672-6495
Motor capacitor part # 628318-313 50uF, 370V
They said any bearing of the correct size (203 Double Seal) can be used since manufacturers have to meet ISO specs for size and performance.
The motor troubleshooting manual is here. It contains directions for testing of capacitor and proper installation bearings.