How To Choose The Right Replacement Pool Pump Motor


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At one point or another, you will need to replace your pool pump motor. Replacing it with an exact match is important otherwise the motor may burn out prematurely. There are a few things to look for when ordering a replacement motor. This guide will help you understand the world of swimming pool pump motors a little better.


Step by Step


Step 1

The easiest way to find out your motor information is on the motor label itself. It will usually list the model or category number. The motor pictured to the left is an AO Smith UST1152 (C48L2N134C1).

Step 2

If you have an AO Smith motor and a part number similar to the UST1152 (C48L2N134C1) is visible, you can enter it into the search by keyword or part number on our website and it will bring you directly to the motor page.

Step 3

Once you're on the motor page, you will find the motor specs listed. You will want to compare and the specs to what is listed on your current motor label. The most important information you will need are the horse power (HP), amps, voltage, service factor (SF), hertz (HZ), frame (FR) and revolution per minute (RPM).

Step 4

If the model or category number is not legible on the motor label, you will need the information on the pool pump (pump housing) to find the right motor. The label will likely include the pump model and the serial number. Unfortunately only the manufacturer has access to the serial number.

Step 5

If you insert the pump model (SP2810X152) in the search box and click go, it should return with a result. Once on the item page, click on the parts tab, then on the replacement parts link.

Step 6

Once on the parts page, you should be able to locate your replacement motor. Once again, you will want to compare and the specs to what is listed on your current motor label (if legible).

Step 7

When I receive a call from a customer asking for a replacement motor, there are a few key questions I will ask: What is the manufacturer and model of the pool pump (not the motor)?, What is the horsepower of the motor?, What is the frame of the motor?, What is the voltage?, What is the service factor?, What is the RPM?, and more general information about the pump (color, shape etc.) if necessary. If all else fails, I will ask for a photo of the pool pump.

Step 8

The reason I ask these questions is because this key information will lead me to a replacement motor. Let's look at the questions: What is the manufacturer and model of the pool pump (not the motor)? If the customer tells me Pentair, then I know that I will likely be looking for a square flange motor (56Y or 48Y frame) because Pentair/Sta-Rite and Jandy (sometimes) use these types of motors for their pumps. The only difference between the 56Y and 48Y is the circumfrence (width) of the motor. They will both mount to the seal plate but the 48Y will need an optional spacer (that comes with the motor) to sit on to make up for the difference in size.

Step 9

If it's a Hayward pump, I will likely be looking for a round flange (56J frame) motor. Jandy also uses 56J frame motors on some of their pump models. This isn't always the case but the questions above will narrow down my search. Once I figure out the type of motor the customer needs, I then try to match up the pump model number or motor specs.

Step 10

If all of the above fails, I will ask for a picture of the pump housing and the motor label.


(41 to 69 of 69)

 Posted: 7/18/2017 

I have a old Megnetek Century Centurion pump(177451) which seems to be working fine, however there is a crack on the housing which need to be replaced. I can find any housing close to that online, the nearest one i see looks like that is WhisperFlo pump Volute( do you have suggestions on finding the right housing.

InyoPools Product Specialist  Posted: 7/9/2017 

TracWagon - You can't put a 1/2 or 3/4 HP motor into a 2HP wet end. The existing impeller is too large to drive with a smaller motor. You would be asking a smaller motor to move the same water flow as the 2 HP motor did. You could change the impeller 1 step down to a 1 1/2 and drive it with a 1 1/2 HP motor. But you can't step the impeller (and motor) all the way down to a 1/2 of 3/4 size.

 Posted: 7/6/2017 

I have converted my pool to a koi pond. Because a koi pond filters are extremely low head we switched to an EE pond pump with a 3hp waterway wet end on a 1/4 hp 48 frame motor. This motor fried but I still have my WFE-8 2hp Pentair whisperflo pump. Because less than 10ft total head is way out of spec for this pump, could I change physically change the motor to a 1/2 or 3/4 56Y frame motor. This would still give the high flow and pull the head specs back into curve?

InyoPools Product Specialist  Posted: 7/4/2017 

Sunny - If your motor label says UST1152, this is your replacement motor - Century 1.5 HP Round Flange Up Rate Motor (C48L2N134) Formerly A.O. Smith - UST1152.

 Posted: 7/3/2017 

Ust 1152
Model c55cxkmc-5013
Hp ? (Can't read it)
Rpm 3450
Volts 230/115
S.f. amps 7.3/15.6 PH1 DUTY
1.10 SF 8.5/17.0 AMPS

that is the best I can read it. I have a Hayward super DUTY I believe. 30,000 gallon.


InyoPools Product Specialist  Posted: 6/23/2017 

Flo - The replacement motor for your current 164303-22 motor is A.O.Smith Motor 56j Thrd Full 1hp (b128).

 Posted: 6/21/2017 

25000 gal inground poolpart 8-164303-22 HP 1.0 Type CX Volts 230/115 AMPS SF 7.2/14.4 HZ 60 RPM 3450 AMB 50C SF 1.4 TIME: CONT Code J ENCL-CR, FR L56J, FORM KJM, INSUL Class: B, Serial # BS6-02
1081 Pool pump duty mount horiz with vent holes down

What pump should we order to replace? Thank you.


InyoPools Product Specialist  Posted: 6/13/2017 

Pete - The replacement motor for your current C48K2N143B3 motor is an A.O. Smith 1 HP Round Flange Up Rate Motor - UST1102. The comparable Energy Efficient motor is an A.O. Smith 1 H.P Pool Motor Energy Efficient Round Flange - UCT1102. At 220V the standard motor uses 7.5 amps. The EE motor uses 5.5 amps. That's an operational savings of 28%.

 Posted: 6/11/2017 

11200 gal inground pool with solar heater, motor runs 365 days in Florida. Motor screeching and getting louder. Hayway Super II pump with cartridge filter. Motor HP and Model # not all readable. Info: FR: 56J, SF:1.1, PH1, model: ?48K2N143B3. Pump:SP3007X10AZ Looking for replacement motor or possibly a more efficient motor/pump if not too expensive. Thanks

InyoPools Product Specialist  Posted: 5/23/2017 

Jeff - You will have difficulty finding a replaceable 56Z motor. The Z-frame uses a flatted shaft end on which the impeller is to be secured. Z-frame motors are usually made in batches to be fitted to a pump manufacturer’s specialty pump. The tricky thing about the flatted shaft is that the width of the flat side varies. So, not all flat shaft Z-frame motors are interchangeable. Your best option is to contact the pump manufacturer to see what he has.

 Posted: 5/21/2017 

Hi, I have a 56z frame pool pump I need to replace what pump would I replace it with? I can't find one

InyoPools Product Specialist  Posted: 5/20/2017 

BrianM - There was not enough information here but from other separate emails on the size of your large pool, it sounds like you need a 1 1/2 HP Hayward Super Pump. With 1 1/2" piping, you shouldn't go any higher.

 Posted: 5/18/2017 

Might need a replacement motor. Can't read much from the pump. It's a Hayward super pump. All I can tell is 56y frame. RPM 3450. Hz 60. Class B 40 degrees. Made in Mexico. Any ideas? Thanks.

InyoPools Product Specialist  Posted: 5/2/2017 

Sean P - I could not match your motor specs to our database. Please give one of our service reps a call at 877-372-6038 to see if they can help you further.

 Posted: 4/29/2017 

Need a replacement motor for my Jacuzzi filter on my above ground pool 18ft, round, my motor is a 1 Hp. 1.0 spl 2 speed a.o smith part no.Part7-186554-01 hz 60 115 volts amps 8.8/2.6 horizontal flow to filter, can you make a suggestion or do you stock this motor. thank you.

InyoPools Product Specialist  Posted: 4/14/2017 

JG - Your replacement motor for Part # 7-164362-22 is Motor 56j Thrd Full 1.5 Hp (b129). The "N" prefix on your frame type is non-standard but has to do with motor length. Check the motor length, shown in one of the motor views, against your current motor to make sure it will fit in your cooler space.

 Posted: 4/13/2017 

I am trying to replace a motor for my milk cooler. The information I have is Century Centurion A.O.SMITH Serial CA11-29 Part 7 -164362-22
Type:CX FR:N56J HP:1.5 SF:1.30 PH:1 HZ:60 RPM:3450 volts 230/115 amps SF 9 2/18.4
Can you tell me where I can order this motor from?
Thanks JG


InyoPools Product Specialist  Posted: 4/10/2017 

Mike - Generally, you cannot replace a 56Z frame with a 56Y frame. The Z-frame uses a flatted shaft end on which the impeller is to be secured. Z-frame motors are usually made in batches to be fitted to a pump manufacturer’s specialty pump.

 Posted: 4/6/2017 

I have a frame of 56Z and can I use a frame of 56Y?

InyoPools Product Specialist  Posted: 2/13/2017 

lee - Sorry, but I can't identify the make of your pump on the information you listed. Please talk to one of our service rep at 877-372-6038. They will probably ask for a couple pictures of your pump.

 Posted: 2/7/2017 

? HI, Im trying to find out what brand my pool pump is and have searched everywhere and cant find it, thanks
?model 72751
?motor model RS4F35712L
?VOLTS 230 HZ 60 HP 1.5


InyoPools Product Specialist  Posted: 2/3/2016 

Susan - Generally the information you need to replace a pump motor is Model Number, the HP, the SF (Service Factor), the FR (Frame). In your case the Model Number may be sufficient. Please call our office at 877-378-6038 and one of our service reps will be happy to look at your motor label pictures and resolve this for you.

InyoPools Product Specialist  Posted: 2/3/2016 

R56J vs 56J - There is no difference. They are the same frame.

 Posted: 2/2/2016 

Just help me please. I have an older motor. Frame:R48Y volts 230/115 rpm: 3450 Serial 186506 Brand Name Magnetek Century Neptuen 1081
amps (all I could read) SF5 What other info do i need and I have pictures


Anonymous  Posted: 2/1/2016 

What is the difference between 2HP AO Smith R56J frame and a 56J without the R?

InyoPools Product Specialist  Posted: 9/10/2015 

Darrin - Not sure what you currently have. Most "Y" frame motors come with a square motor mounting flange that attaches to the seal plate. If you haven't already, please call our office at 877-372-6038 and talk to one of our service reps. The will be able to clear up any confusion quickly.

 Posted: 9/2/2015 

Hi, it says above that a 56Y and 48Y will both mount to the seal plate but the 48Y will need an optional spacer (that comes with the motor) to sit on to make up for the difference in size. I have a motor that I need to replace. It is a 56Y but it does not have the square plate on the end of the one like this one - I just need the motor. Can you help me determine which one is right for me, please? I can send photos and details, too.

InyoPools Product Specialist  Posted: 8/3/2015 

Art in fl - No, a 56J motor (round) cannot fit on a 56Y frame (square).

 Posted: 8/1/2015 

Can you use a 56j motor on a 56y frame