US Motors pool pump motor replacement Nidec AST165 1.65 THP 56J C-flange dual-voltage (115/230V)

If your pool pump motor has burned out or is underperforming, this 1.65 Total Horsepower (THP) motor from Nidec (marketed under US Motors compatibility) is designed to drop into a wide range of pumps and get circulation back to spec. It uses a standard 56J frame and a C-flange with a threaded shaft to match common pool pump mounts, and it supports both 115 and 230 volt wiring so installers can adapt to existing electrical configurations.

Will this motor fit my Hayward or Pentair pump?

Yes — the Nidec AST165 replacement is intended as a direct-fit option for many domestic pool pumps that accept a 56J C-flange motor. It's sized to replace certain 1.5 HP up-rated and 1.0 HP full-rated motors and matches common bolt patterns and shaft threading used by major brands.

• Standard 56J-frame C-flange with four 3/8" threaded bolt holes at 1, 5, 7 and 11 o'clock
• Threaded shaft compatible with many pump impellers
• Compatible brands: Hayward, Pentair, Jacuzzi, Jandy, American Products, Astral

How do voltage and wiring options work for this motor?

This motor is dual-voltage capable and can be wired for either 115V or 230V service, giving flexibility during installation. Confirm your pump’s original wiring and breaker size; if unsure, consult an electrician to match voltage, starter, and overload protection to local electrical codes.

• Prepped for 115/230 volt operation; rewireable per manufacturer instructions
• Check motor nameplate and pump wiring diagram before installation
• Use a certified technician if you need to change voltage configuration

What are the mechanical mounting and performance details?

The motor uses a C-flange mount with a 56J frame and four 3/8" bolt holes positioned at clockface locations common to pool pump motors. At 1.65 THP it provides performance between conventional 1.5 HP up-rated and 1.0 HP full-rated motors, intended to restore or improve pump output depending on your hydraulic setup.

• 1.65 Total Horsepower (THP) rating for restored pump performance
• 56J frame and C-flange for common mechanical compatibility
• Four 3/8" threaded mounting holes at 1, 5, 7 and 11 o'clock positions

Who this motor is for: pool owners, service technicians, and maintenance pros who need a reliable, drop-in replacement for a failed or underpowered pump motor. If your pump’s original motor used a 56J C-flange and threaded shaft, and you require a flexible 115/230V option with a modest power boost to 1.65 THP, this Nidec AST165-compatible motor is a practical choice. Always verify shaft size, bolt-hole pattern, and electrical requirements before purchase, and consult a qualified installer if you are not comfortable with motor replacement or rewiring.