4BTA3.9 Diesel Engine

The 4BTA3.9 diesel engine is a 4-cylinder, 4-stroke, water-cooled engine with turbocharger and air intercooler.
As a representative model of the Cummins B Series, it is well-known for its high reliability, strong torque output, and excellent durability.

With a displacement of 3.9 liters, the 4BTA3.9 provides stable power performance even under heavy-duty and continuous operation conditions, making it an ideal power solution for both on-road and off-road applications.

 Key Features & Advantages

• Turbocharged & Aftercooled (T/A)
  Improved power density and fuel efficiency.

• Excellent Low-Speed Torque
  Delivers strong torque at low RPM, ideal for construction machinery and generator sets.

• Fuel Efficient PT / Electronic Fuel System
  Early models use Cummins PT fuel system; later models adopt electronic control for better efficiency.

• Long Service Life & High Reliability
  Rugged cylinder block design; known in the market as a “workhorse engine”.

• Easy Maintenance & Global Parts Availability
  Spare parts are widely available, reducing downtime and operating cost.

Applications

• Construction Machinery
  Loaders, excavators (small & medium), forklifts, air compressors, cranes, road machinery

• Power Generation
  Diesel generator sets (typical output range: 80–100 kW)

• Commercial Vehicles
  Medium-duty trucks (5–8 tons), buses, coaches, school buses

• Special Vehicles
  Fire trucks, sanitation vehicles, recovery trucks

• Marine Applications
  Small cargo vessels, fishing boats (main engine or auxiliary engine)

• Agricultural Machinery
  Medium & large tractors, harvesters

Technical Specifications

Engine Model Series:  4BTA3.9 – II