Stock motor from what I read was 1.0 or 1.5Hp @1100 RPM, so probably a 6 pole for 60Hz. A 2Hp or 3Hp 4P motor could be used, when you reduce the speed with a VFD the Hp decreases in a linear fashion so a 3 Hp motor is making around 1.8 Hp at 1100 RPM. The torque would also be reduced based on the difference between a 4P and 6P, so a bit of a wash on that end. You can also reduce the motor overload point with a VFD so you can run it at say 100 or 120%, the default is typically 150%. A standard motor has a higher locked rotor current when running off the line voltage. There can be cooling issues with a TEFC motor when you run them below 15Hz for any continuous duty time under load. If you can find a 6P 2Hp motor than would be a close replacement, but either a 2 or 3Hp 4P, or 6P 1.5 or 2 Hp would work well.
Marathon 184TTFB6078 2Hp Premium General Purpose Globetrotter Electric Motor. Catalog #: GT1208. New open box. Works as designed. Assembly : F1 (F2 Modification Available). Drive End Bearing : BALL.
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Manufacturer's ID: P18G4904. Manufacturer: RELIANCE ELECTRIC. Design: B Catalog RPM: 1200. Condition: New Surplus. Service Factor: 1.15 Insulation Class: F Ambient Temp: 40 C.
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