4BTAA3.9-G58

The compact, lightweight, and cost-effective Type B engine delivers cleaner and quieter performance, with a rated power output of 50 kW. Under strict adherence to maintenance guidelines, it achieves a mean time between failures (MTBF) of 1,500 hours and a mean time between overhauls (TBO) of 6,000 hours or more. Even under extreme duty cycle testing, this model maintains strong performance. Its low noise levels, reduced weight, and high power-to-weight ratio are all attributable to its world-class reliability.

Basic Specifications

• Compression Ratio: 10.5:1
• Bore: 102 mm
• Stroke: 120 mm
• Emission Control: ≤3%
• Aspiration: Turbocharged & Air-to-Air Intercooled
• Displacement: 3.9 L
• Number of Cylinders: 4
• Test Condition: Engine equipped with water pump and oil pump; without air compressor, generator, fan, optional parts and driving parts; intake resistance 3.7 kPa, exhaust resistance 10 kPa
• Flywheel Interface: 3#/11.5
• Dimensions (Standard Configuration, mm): 1080×625×1085
• Maximum Continuous Operating Altitude: 2200 m
• Performance Test Conditions: Atmospheric pressure 100 kPa, intake air temperature 25 °C, tested per GB/T18297

Engine Power Data

Performance Data at 1500 RPM

Performance Data at 1800 RPM

Typical Engine Data

• Dry Weight: 411 kg
• Transient Moment of Inertia (Without Flywheel): 0.25 kg·m²
• Distance from Center of Gravity to Front Face of Cylinder Block: 391 mm
• Distance from Center of Gravity to Crankshaft Centerline (Above Crankshaft): 140 mm
• Firing Order: 1-3-4-2

Engine Mounting

• Maximum Allowable Static Bending Moment at Rear Face of Cylinder Block: 1356 N·m

Exhaust System

• Maximum Exhaust Back Pressure: 10 kPa

Charge Air Cooling System

• Maximum Allowable Temperature Difference Between Intake Manifold and Inlet Air: 25 °C
• Maximum Allowable Pressure Drop Across Intercooler: 13 kPa
• Maximum Allowable Intake Manifold Temperature (Ambient 25 °C): 50 °C
• Maximum Allowable Intake Manifold Temperature: 58 °C

Intake System

• Maximum Allowable Intake Resistance (Heavy-Duty Air Cleaner)
  • Clean Filter Element: 3.7 kPa
  • Dirty Filter Element: 6 kPa
• Minimum Dirt Holding Capacity of Heavy-Duty Air Cleaner: 53 g/litre/sec
• Maximum Temperature Rise from Ambient Air to Turbocharger Inlet: 17 °C
• Recommended Minimum Inner Diameter of Intake Pipe: 76 mm

Lubrication System

• Normal Operating Oil Pressure Range
  • Low Idle: 207 kPa
  • Rated Speed: 345 kPa
• Maximum Oil Sump Temperature: 121 °C
• Oil Capacity (Offset Oil Sump): Max. 14.2 L – Min. 12.3 L
• Minimum Lubrication System Capacity (Oil Sump + Oil Filter): 16.4 L
• Inclination Angle with Offset Oil Sump
• Front Up: 40°
• Front Down: 40°
• Side to Side: 40°

Cooling System

• Coolant Capacity (Engine Only): 10 L
• Maximum External Cooling Circuit Resistance
  • 1800 RPM: 35 kPa
  • 1500 RPM: 28 kPa
• Maximum Static Coolant Height Above Crankshaft Centerline: 1.4 m
• Standard Thermostat Opening Temperature (Range): 82–95 °C
• Minimum Pressure Cap Pressure: 69 kPa
• Maximum Coolant Temperature at Standby/Rated Power: 104 °C / 100 °C

Electrical System

Item	Unit	Specification
Starter	volt	12V / 24V
Battery Charging System (Negative Ground)	ampere	63 / 40
Maximum Starting Circuit Resistance	ohm	0.00075 / 0.002
Minimum Battery Capacity (Cold Soak at -12 °C or Above)	CCA	800 / 400

Emission Data (Tested per GB 20891-2007)

At Rated Speed 1500 RPM

At Rated Speed 1800 RPM

Additional Operating Parameters

Item	Unit	Standby Power		Rated Power
		1800 RPM	1500 RPM	1800 RPM	1500 RPM
Low Idle Speed	rpm	750–850	750–850	750–850	750–850
Output Power	kW	64	58	55	50
Piston Speed	m/s	7.2	6.0	7.2	6.0
Friction Loss Power	kW	9.3	8.7	8.5	6.4
Engine Coolant Flow	litre/sec	2.4	2.0	2.4	2.0
Intake Air Flow	litre/sec	43.0	32.9	43.0	32.8
Exhaust Gas Flow	litre/sec	81.9	71.0	78.5	67.5
Exhaust Temperature	°C	570	540	540	500
Air-Fuel Ratio	air:fuel	12:1	12:1	12:1	12:1
Ambient Heat Loss (Dry Manifold)	kW	20	18	18	16
Coolant Heat Loss (Dry Manifold)	kW	38	35	25	25
Exhaust Heat Loss	kW	54	48	45	40