Phasor KK4-21.0 – 21kW Keel Cooled Diesel Generator 60Hz

The Phasor KK4-21.0 is a high-output keel-cooled marine diesel generator for vessels requiring 21 kW of 120/240V single-phase 60Hz AC power. It uses a Kubota V2403-M-E4BG four-cylinder diesel engine operating at 1,800 RPM and a direct-coupled brushless generator with solid-state voltage regulation. The open-frame model is designed for vessels using a closed-loop keel-cooling, grid-cooling, or skin-cooling system rather than a conventional raw-water heat exchanger.

The generator uses an engine-driven coolant circulation pump and must be connected to a cooling circuit designed for its heat-rejection requirement. It includes a remote instrument panel with oil-pressure, coolant-temperature, voltage, and hour-meter gauges, plus automatic low-oil-pressure and high-coolant-temperature shutdown. An optional sound enclosure may be selected separately for installations requiring lower measured sound output.

Key Specifications

- Heavy-duty keel-cooled marine diesel generator for 120/240V single-phase 60Hz AC systems.
- Provides 21 kW continuous output at 1,800 RPM.
- Uses a Kubota V2403-M-E4BG four-cylinder diesel engine with approximately 2,434 cc displacement.
- Provides 120/240V output with approximately 175A at 120V or 87.5A at 240V.
- Uses a direct-coupled brushless generator with solid-state voltage regulation.
- Requires a closed-loop keel-cooling, grid-cooling, or skin-cooling circuit.
- Fuel consumption is listed at approximately 1.7 US gallons per hour, or 6.4 L per hour, at full load.
- Open-frame generator measures approximately 1,168 mm by 584 mm by 686 mm and weighs approximately 408 kg.

Electrical Compatibility

This generator is intended for 120/240V single-phase 60Hz systems. Confirm the vessel electrical distribution arrangement, continuous load, simultaneous demand, power factor, motor-starting surge, and future load expansion before selecting a 21 kW genset. If three-phase output is required, verify the correct alternator configuration rather than assuming it is included with the standard single-phase model.

Generator capacity should account for HVAC, watermakers, refrigeration, battery chargers, pumps, galley appliances, and all other connected loads. High-demand inductive loads can require significant start-up capacity beyond their normal running wattage.

Installation Considerations

Install the generator on a rigid vibration-isolated foundation designed for approximately 408 kg, with full access for oil, filters, coolant, electrical terminals, exhaust, and optional enclosure components. Connect the closed cooling loop to a correctly sized keel cooler, grid cooler, or skin cooler and verify coolant flow, hose size, air bleeding, expansion tank capacity, and heat rejection. Add fuel supply and return, exhaust, ventilation, starting battery, AC distribution, grounding, and shore-power transfer isolation. Installation and commissioning should be completed by a qualified marine generator technician.

Before Ordering

Confirm required continuous and surge load within 21 kW, 120/240V single-phase 60Hz compatibility, exact phase requirement, adequate keel-, grid-, or skin-cooling circuit, available installation space, structural support for approximately 408 kg, sound-enclosure requirement, diesel fuel layout, exhaust route, ventilation, starting-battery circuit, AC distribution and transfer-switch design, grounding plan, service access, and qualified installation requirements before purchase.