Product Description

The Cummins 4B3.9-G1 Generator Drive Engine is a 3.9L, 4-cylinder, naturally aspirated diesel engine designed for small generator set applications. With a maximum rating of 27 kW (36 HP) at 1500 rpm, this compact and fuel-efficient engine is ideal for light industrial, commercial, and backup power needs.

Backed by Cummins’ engineering excellence, the 4B3.9-G1 delivers reliable power generation, low operating costs, and long service life, making it a trusted choice for entry-level generator sets.

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Specifications

• Engine Model: Cummins 4B3.9-G1
• Application: Generator Drive Engine
• Displacement: 3.9 L
• Configuration: 4-cylinder, in-line
• Bore × Stroke: 102 × 120 mm
• Compression Ratio: 17.3:1
• Aspiration: Naturally Aspirated

• Fuel System: BYC A/RSV Mechanical Direct Injection

Power Ratings (1500 rpm):

• Standby: 27 kW (36 HP)

• Prime: 24 kW (32 HP)

Fuel Consumption (at 1500 rpm):

• 100% Load (27 kW): 8.0 L/h

• 100% Load (24 kW): 7.1 L/h

Lubrication System:

• Oil Capacity: 8.5–9.5 L
• Minimum System Capacity: 10.9 L

• Max Oil Temperature: 121 °C

Cooling System:

• Coolant Capacity (engine only): 7.2 L
• Thermostat Range: 82–95 °C

• Max Coolant Temp: 100–104 °C

Weight: 308 kg (wet)

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Product Advantages

• Compact & Efficient – Lightweight 3.9L engine with low fuel consumption.
• Reliable Power – Provides up to 27 kW standby output for small generator sets.
• Low Operating Cost – Efficient fuel burn with consumption as low as 2.8 L/h at 25% load.
• Durable Build – Robust Cummins design ensures long service life.

• Global Support – Genuine Cummins engine backed by worldwide service network.

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Key Features

• Naturally aspirated design for simplicity and ease of maintenance.
• Optimized for 1500 rpm, 50Hz generator sets.
• Stable governor regulation ≤8%.
• Mechanical direct injection fuel system.

• Compact design ideal for small and portable generator applications.

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Applications

The Cummins 4B3.9-G1 Diesel Engine for Generator Sets is best suited for:

• Small Commercial Backup Power – shops, offices, and small facilities.
• Light Industrial Power – workshops, farms, and rural operations.
• Residential & Community Power – backup during outages.

• Mobile & Rental Generators – compact gensets for temporary power.

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Product Availability

The Cummins 4B3.9-G1 Generator Drive Engine is available globally with genuine Cummins warranty, service, and spare parts support, ensuring reliable operation and longevity for your power generation needs.