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Century BN51 Replacement

The Century BN51 is a 2/0.25 HP two-speed pool/spa motor (48Y thru-bolt, 3450/1725 RPM, 230V). Below: the specs we verify before quoting, and what to check on your nameplate.

Verified specifications

Horsepower2 HP high / 0.25 HP low
Speed3450/1725 RPM (two-speed)
Voltage230V, single-phase, 60 Hz
Full-load amps10.5/2.6A
Service factor1.0
Frame48Y (thru-bolt)
EnclosureODP
Motor typeCapacitor start
RotationCCWSE (verify on nameplate — unusual for pool motors)
Shaft1/2" threaded (3/8-16 UNC-2A)
BearingsBall bearings
Thermal protectionAutomatic
InsulationClass B
MountingRigid base

Pool-duty motors: match the total HP (HP × service factor) to your pump's requirements, and confirm full-rated vs up-rated before swapping.

Dual branding: this stock number is sold interchangeably as Century and A.O. Smith — the same Regal Rexnord motor. See the A.O. Smith BN51 page.

The 2 HP sibling of the Century BN62 (3/0.38 HP) — above-ground pool, spa, and jetted-tub duty.

Confirming the right replacement

Before we quote, compare these fields on your failed motor's nameplate. If any of them differ, send us a photo of the nameplate and we'll match it exactly rather than guessing:

Other Century models

Need a Century BN51?

Send the nameplate off your failed unit. We'll confirm the match and quote the BN51 or a verified equivalent with availability and lead time.

Quote this motor