Century (A.O. Smith) .75 HP Full Rate Motor, Round Flange 56J Frame, Single Speed - Model ST1072



Part # ST1072

By Century Motors

  4.89 Average  



Part # ST1072

Warranty 1 Year

Dimensions 12.5" L x 6" W x 6" D

Alternate Part #'s 11028, 15443, 15925, 164564, 165111, 177024, 177842, 19135, 1K046, 317P809, 5KC33MN2514X, 5KCR39PN2906AX, 5KCR39PN2906X, 82305, 91723, B127, B137, B626, B638, B988, C1099, C1437, C488, C48J2N118, C48J2N122A1, C48J2N131HH, C48K2DA144, C48K2DB141A1, C48K2N102, C48K2N104, C48K2N106, C48K2N113, C48K2N117A1, C48K2N117A3, C48K2N117A7, C48K2N117A8, C48K2N119, C48K2N120, C48K2N122, C48K2N122A2, C48K2N124, C48K2N126, C48K2N142, C48K2N142A3, C48K2N142A4, C48K2N143B1, C48K2N143B3, C48K2N143B4, C48K2N143C2, CT107C, EB127, JD75FL1, M543, S88-171, SP1605Z1MP, SPX1605Z1M, ST1072, SW2558, T1072, V15443, 35-126-3022, AOS-60-5063, AOSST1072

Product Description

Voltage 115/230, Max Amps 115V = 15.0 230V = 7.5, Single Speed, Round Flange, RPM = 3450, Threaded Shaft, Frame = 56J Used on the following FULL RATE ENERGY EFFICIENT models: Hayward Super II Energy Efficient, Hayward Northstar Full Rate and Jacuzzi Magnum Full Rate pumps.

Note: NOT California Title 20 Compliant. 

California Title 20 Compliant Options:

Motor Dimensions Motor Dimensions
Motor Image Motor Image

Product Specifications

Motor Name:
0.75 HP ST1072 Replacement Pool Motor
0.75 HP
3450 RPM
115/230 V
15.0/7.5 amp
Service Factor:
Total HP:
1.13 HP
Stock #:
Overload Protector:
Dimension Letter:
11 in.
Commonly Used On:
Hayward Max Flow, Hayward Super Pump, Hayward Super II, Hayward Northstar and Jacuzzi Magnum
NOT California Title 20 Compliant

?     Asked on 8/22/2022by Lalit Gupta

My exiting pump is SP2605X7, Serial number 21120707000832005. I need a replacement motor, can you tell me which one I need. I cannot read the info on the existing motor. Also the impeller. Thanks

A  Answered on 11/30/2022 by InyoPools Product Specialist Hector F.

Hello Lalit, the direct single speed motor replacement for your Hayward Super Pump model SP2605X7 is the motor model UST1072. We also recommend replacing the seals and gaskets when replacing a pool pump motor. Please click here to view both the standard and saltwater pool tune up/seal kits for your series pool pump.   

?     Asked on 4/11/2021by Cathy Lanier

I have the AO Smith ST1072 3/4 HP 3450 RPM, 1.5 Service Factor, 56J Frame, Capacitor Start, ODP Enclosure, C-Face Pool Motor. Can you tell me the compatible impeller I need to go with it?

A  Answered on 4/22/2021 by InyoPools Product Specialist Matt S.

The pump hardware parts are matched to the pump housing and not solely on the motor. What is the model number or make and model of the pump housing?

?     Asked on 10/11/2020by Ruben Meza

i have a motor with the exact specs as this century motor except mine says it is an A.O Smith but the label description is exact except for ser number. mine says 8g02. A bit confused as to what motor i have and how to look for go-kits.


A  Answered on 10/20/2020 by InyoPools Product Specialist Joe S.

Hello Ruben, yes if you match the specs on the motor they should be the same. The serial numbers would be different like a VIN number on a car. Based on the photo you would need the Tune Up Kit Hayward Super II - GOKIT2.

?     Asked on 2/12/2019by Brad Talley

1st time pool owner! Need a replacement motor for my spa blower pump. I have a hayward system and this blower to the spa quit working and I need to know what motor I need to replace this with and any other parts that will be required to change the motor to the blower and if possible to re-use the blower.


A  Answered on 2/12/2019 by InyoPools Product Specialist Lennox H.

Hi, Brad. The replacement motor is Part # SPX2705Z1M.

?     Asked on 6/9/2018by Hugh Phillips

whats the difference between a st1072 and a ust1072

A  Answered on 6/9/2018 by InyoPools Product Specialist Alex V.

Hugh, The ST1072 if a full rated motor (high service factor) and the UST1072 is an up-rated motor (low service factor). You need to match the horse power and service factors among other specs to make sure you are buying the correct motor. 

?     Asked on 2/21/2018by Inyo Visitor

I have a leak on my Hayward booster 5060.. when I turn on the booster the leak appears to be a pressured stream coming from the seam of the volute. Will this leak compromise the pumping or suction action on my piping system even when not activated? (It does not leak when not in use)

A  Answered on 2/21/2018 by InyoPools Product Specialist Lennox H.

Hi. If the leak is not resolved it will get worst causing a major issue with the pump, and or the performance of your cleaner. It may not be an issue when the pump is not running but it just depends on the severity of the leak. 

?     Asked on 4/24/2017by correct booster pump

I'm looking for the proper replacement booster pump for a Hayward Model 5060 series 8d07. The current motor has a SF of 1.85 and a HP of 3/4, totalling 1.3875 HP. According to your own info replacement motor HP should be equal to or greater then the original. But the motor you list as the replacement In another Q/A for the 5060, is the SPX2707Z1M with a square Flange. Also you list the ST1072 which has a round flange. Neither meet the HP requirment as my current motor. So which is it?

A  Answered on 4/25/2017 by InyoPools Product Specialist Scott W.

Hayward has part number SPX2707Z1M for the replacement motor for that booster pump, but you could also use part number SQ1072 for that booster pump. Also, that booster pump requires a square flange motor not a round flange motor. The shaft seal you will need for your motor install is part number 3260-105.

?     Asked on 4/24/2017by capacitor

Does this motor have a starter capacitor under the motor housing? If "yes" what is the replacement part.

A  Answered on 4/25/2017 by InyoPools Product Specialist Patrick P.

Yes this motor does have a start capacitor which is located underneath the motor cover on the back of the motor. The capacitor # for this motor is a 610807-002 Start Capacitor We also have a Video on How to Replace a Pool Motor Start Capacitor which you may find helpful.

?     Asked on 8/31/2016by Joe Cook

What is the difference between an UP rate motor and a Full rate motor?

A  Answered on 8/31/2016 by InyoPools Product Specialist Stacey M.

Hello Joe, there is a "how to" on Up rated and Full rated.

?     Asked on 6/30/2016by Mike

I have a Hydramax 2 pump and the motor part # SP1607Z1BEP 3/4 HP Motor Frame is N56J 3450RPM. Is this motor compatible?

A  Answered on 6/30/2016 by InyoPools Product Specialist Megan C.

Hello, Mike. The PART#BN24 3/4 HP 115V Thru Bolt Motor and the PART#BN36 3/4 HP 2 Speed 115V Thru Bolt Motor are the options for replacement motors. The Hydramax Shaft Seal Assembly will also require replacement anytime you replace your motor. The part numbers available for those are PART#5111-03 (Generic) and the PART#5111-03C (OEM). You may click here to view the schematic, for all parts available to order for the pump.

?     Asked on 6/1/2016by Inyo Visitor

I'm looking for a inground pool Hayward booster pump model C48K2N143B4, SER NO.8E06, Model 5060, is this pump? Thanks

A  Answered on 6/1/2016 by InyoPools Product Specialist Lennox H.

Hi, The SPX2707Z1M motor is the correct replacement for the Hayward 5060 pump.

?     Asked on 4/21/2016by Robert Wilson

Hi, The replacement for my current motor is listed as UST1072. It seems the only difference from the ST1072 is the service factor. Can I use an ST1072 instead of a UST1072 or is the service factor a game breaker?

A  Answered on 4/22/2016 by InyoPools Product Specialist Hector F.

The ST1072 is a stronger motor so you may need to change the impeller if it was originally set up for the UST1072. Also the filter may not be able to handle the extra water pressure.

?     Asked on 1/19/2012by Guest

I'm trying to replace the motor on my pool pump but all these numbers and abbreviations on the motor label are really confusing me. What do they mean?

A  Answered on 1/19/2012 by InyoPools Product Specialist Patrick P.

Replacing a pool pump motor is not as difficult as it seems. You can try looking here. If you need help figuring out what the information on your label means. If you are still having difficulty figuring it out you can call us at our toll free number or you can send us a photo of your motor label here.

?     Asked on 1/18/2012by Guest

I'm trying to find a replacement motor for my pool pump but my model number doesn't match what you have listed as the model number. My model number begins with a C48 and yours begins with an SP. Please help.

A  Answered on 1/18/2012 by InyoPools Product Specialist Patrick P.

What we have listed on our chart pages is the pump model number. The model number you have will just identify the motor. If you look on the plastic housing on the pump there should be a sticker which will have the pump model number. You can usually find this by the discharge port on the pump. Once you locate it you can choose the correct replacement motor. Be certain to change the shaft seal and gaskets as needed. You can use our >How to guide if you need help. 

?     Asked on 1/12/2012by Guest

Why should I purchase a Tune Up Kit?

A  Answered on 1/12/2012 by InyoPools Product Specialist Patrick P.

A Tune Up Kit includes all of the essential replacement seals and gaskets for the pump. The seals and gaskets should be replaced when installing a new motor on your pump. New seals will prevent the pump from leaking water or losing the prime. A Tune Up Kit will protect your motor and ensure that the pump is working efficiently.

?     Asked on 1/12/2012by Guest

Why do I need to purchase a new shaft seal?

A  Answered on 1/12/2012 by InyoPools Product Specialist Patrick P.

We strongly recommend replacing the shaft seal. The purpose of a shaft seal is to prevent water from running down the shaft of the motor and into the motor housing. Water will damage the bearings and cause the motor to fail. A new shaft seal should be installed whenever a motor is replaced. The motor manufacturer can deny the warranty if the motor fails to due to water damage from a faulty shaft seal. To find your shaft seal you will need to visit our Pool Pump Parts Page or the Spa Pump Parts Page and select your make and model.

?     Asked on 1/11/2012by Guest

What is Service Factor?

A  Answered on 1/11/2012 by InyoPools Product Specialist Patrick P.

Service Factor(SF) is a multiplier that when multiplied by the horsepower of the motor indicates the total permissible horsepower loading that may be carried when the motor is operating at rated voltage and frequency. The most important thing to remember when replacing a motor is that the replacement motor's horsepower times its service factor must be equal to or greater than the original motor's horsepower times its service factor. The Service Factor rating can be found on the motor label. See Step 4 of our How to Read a Pool Motor Label guide.


Est. Repair Time

1 to 2 hrs

Tools Needed

Screwdriver, Socket Set, Wrench Set

Electrical storm fried the motor

Written on 8/6/2019 by Guest

Replacement motor came fast and the only problem was I failed to order a new seal pack. Ordered that and installation was simple. Every thin was a direct match. Very satisfied.

Were these instructions helpful? 


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