A.O. Smith 2 HP Round Flange 56J Dual Speed Full Rate Motor - B2979



Part # STS1202

By Century Motors

  5 Average  



Part # STS1202

Warranty 1 Year

Manufacturer Code B2979

Alternate Part #'s 1105170400, 152687, 158227, 158568, 159819, 159820, 159945, 1620Z-2-MC, 1620Z-2-MSC, 165980, 177064, 177107, 177111, 177112, 177153, 181094, 181389, 181390, 190041, 190066, 190116, 190126, 190128, 190178, 190191, 190217, 190218, 19315, 193637, 1D194, 35B1200, 817706405, A0564800, B2979, B929, B941, B959, B979, C1443, CT120T, EB979, JH20FL2, MGT605118, SP-1620-Z2-MC, SP-1620-Z2-MSC, STS1202RV1

Product Description

Voltage 230, High Speed HP = 2.0 Low Speed HP = 1/3, Max Amps @ High HP = 11.4 Max Amps @ Low HP = 4.1, Dual Speed, Round Flange, RPM @ High Speed = 3450 RPM @ Low Speed = 1625, Threaded Shaft, Frame = 56J Used on the following DUAL SPEED pump models: Hayward Max Flow, Hayward Super Pump, Hayward Super II, Hayward Northstar and Jacuzzi Magnum pumps. 



Motor Dimensions Motor Dimensions
Motor Image Motor Image

Product Specifications

Motor Name:
2 HP STS1202 $ STS1202RV1 Replacement Pool Motor
2/ .3 HP
3450/1725 RPM
230 V
11.4/4.1 amp
Service Factor:
Total HP:
2.4 HP
Stock #:
STS1202 or STS1202RV1
Overload Protector:
Dimension Letter:
13 - 3/4 in.
Commonly Used On:
Hayward Max Flow, Hayward Super Pump, Hayward Super II, Hayward Northstar and Jacuzzi Magnum
California Title 20 Compliant

?     Asked on 6/21/2018 by Matt Nielsen

Currently have a Century KM48M2N111, a single speed 2hp motor. Would this model work as a replacement?

A  Answered on 6/22/2018 by InyoPools Product Specialist Lennox H.

Hi, Matt. Yes, this Dual Speed Motor - B2979 will work as a replacement for Model # K48M2N111. 

?     Asked on 10/30/2014 by

I ordered a B979 motor. Is the B2979 an exact replacement or is there anything different I must do when installing this motor. Will the seal be different than the one specific to the B979. Thanks for your help.

A  Answered on 10/31/2014 by InyoPools Product Specialist Robert M.

The B979 and the B2979 are the same motor. The installation will be exactly the same. The manufacturer changed the part numbers to this series of motors a couple of years ago. The seal will be the same as well.

?     Asked on 1/19/2012 by 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 1/18/2012 by Guest

How can I tell whether or not my motor is a dual or single speed?

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

Most dual speed motors will have a toggle switch that will allow you to adjust the motor speed to either high or low. Another way to tell if your motor is dual speed is by looking at the RPM's on the motor specifications label. If there are two RPM's listed such as: 1725/3450 then motor is dual speed. If there is only one RPM, then motor is single speed.

?     Asked on 1/18/2012 by 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 1/18/2012 by Guest

Can you direct me to the proper hi low switch for this motor?

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

Unfortunately the manufacturer does not offer the switch for the 2 speed 220v motors any longer. If you already have a 220 volt timer (on/off) you would need an Intermatic T106R to switch from high to low speed. If you do not have a timer currently you would need the T10604R which is a 220v on/off timer and a high/low timer.

?     Asked on 1/12/2012 by 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 1/12/2012 by 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 1/11/2012 by 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.

?     Asked on 5/16/2007 by Guest

Can you replace single speed pump motor with dual speed pump motor?

A  Answered on 5/16/2007 by InyoPools Product Specialist Patrick P.

Yes but you can't go with a higher HP than the single speed motor. For example if you have a 1 HP single speed you cannot go with a 1.5 HP dual speed motor; you would be able to use a 1 HP dual speed motor. Customer would need to purchase a toggle switch or timer to switch from high speed to low speed.


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