The D381036MX02 is a 3.9 L 4-cylinder naturally aspirated engine rated at 1500 rpm, producing up to 41 kW. It powers generator sets from Cummins/Onan, including the 4B3.9. It holds 132 L (34.9 gal) of coolant.
Also known as: D381036MX02
| Coolant capacity | 132.0 L |
|---|---|
| Displacement | 3.9 L |
| Cylinders | 4 |
| Aspiration | Naturally Aspirated |
| Rated speed | 1500 rpm |
| Gross power | 41 kW |
| Item | Action | Hours | Months | Notes |
|---|---|---|---|---|
| Air intake system | Inspect | 500 hr | 6 mo | Every 19,000 km [12,000 mi], 500 hours, or 6 months |
| Antifreeze | Check | 1000 hr | 12 mo | Every 38,000 km [24,000 mi], 1000 hours, or 1 year |
| Valve lash clearance | Adjust | 1000 hr | 12 mo | Initial adjustment at 38,000 km [24,000 mi]; subsequent at 77,000 km [48,000 mi] |
| Air cleaner filter | Inspect | 2000 hr | 24 mo | Every 77,000 km [48,000 mi], 2000 hours, or 2 years |
| Air compressor | Inspect | 2000 hr | 24 mo | Every 77,000 km [48,000 mi], 2000 hours, or 2 years |
| Antifreeze | Change | 2000 hr | 24 mo | Every 77,000 km [48,000 mi], 2000 hours, or 2 years |
| Belt tension | Check | 2000 hr | 24 mo | Every 77,000 km [48,000 mi], 2000 hours, or 2 years |
| Belt tensioner | Inspect | 2000 hr | 24 mo | Every 77,000 km [48,000 mi], 2000 hours, or 2 years |
| Charge air cooler (CAC) | Check | 2000 hr | 24 mo | Every 77,000 km [48,000 mi], 2000 hours, or 2 years |
| Cooling system | Drain | 2000 hr | 24 mo | Every 77,000 km [48,000 mi], 2000 hours, or 2 years; drain/flush/fill |
| Fan hub | Inspect | 2000 hr | 24 mo | Every 77,000 km [48,000 mi], 2000 hours, or 2 years |
| Fuel filter | Replace | 2000 hr | 24 mo | Every 77,000 km [48,000 mi], 2000 hours, or 2 years |
| Intake system | Inspect | 2000 hr | 24 mo | Every 77,000 km [48,000 mi], 2000 hours, or 2 years |
| Lubricating oil | Change | 2000 hr | 24 mo | Every 77,000 km [48,000 mi], 2000 hours, or 2 years |
| Lubricating oil filter | Replace | 2000 hr | 24 mo | Every 77,000 km [48,000 mi], 2000 hours, or 2 years |
| Vibration damper | Inspect | 2000 hr | 24 mo | Every 77,000 km [48,000 mi], 2000 hours, or 2 years |
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
| Type | Item | Value | Unit | Condition |
|---|---|---|---|---|
| Clearance | Air compressor carbon deposit thickness maximum | 1.6 | mm | 1/16 inch |
| Clearance | Crankshaft end play | 0.127 to 0.431 | mm | 0.005 to 0.017 in |
| Clearance | Cylinder block flatness end-to-end maximum | .076 | mm | .003 in |
| Clearance | Cylinder block flatness side-to-side maximum | .051 | mm | .002 in |
| Clearance | Cylinder head flatness end-to-end maximum - 4 cylinder | .203 | mm | .008 in |
| Clearance | Cylinder head flatness end-to-end maximum - 6 cylinder | .305 | mm | .012 in |
| Clearance | Cylinder head flatness side-to-side maximum | .076 | mm | .003 in |
| Clearance | Exhaust Manifold Flatness | 0.10 | mm | MAX |
| Clearance | Flywheel Bore Alignment T.I.R. | 0.020 | mm | MAX, SAE No. 1, 2, 3 |
| Clearance | Flywheel Bore Runout T.I.R. | 0.127 | mm | MAX |
| Clearance | Gear backlash - all gears | 0.08 to 0.33 | mm | 0.003 to 0.013 in |
| Clearance | Lubricating oil pump gerotor drive/planetary to port plate maximum | 0.381 | mm | 0.015 in |
| Clearance | Lubricating oil pump gerotor planetary to body bore maximum | 0.127 | mm | 0.005 in |
| Clearance | Lubricating oil pump tip clearance maximum | 0.1778 | mm | 0.007 in |
| Clearance | Tensioner spring case to arm clearance (max) | 3 | mm [0.12 in] | |
| Clearance | Turbocharger Wastegate Actuator Rod Travel | 5 | mm | approximately, without sticking or air leakage |
| Clearance | Turbocharger end play - serial number 840638 and after | 0.03 to 0.08 | mm | 0.001 to 0.003 in |
| Clearance | Turbocharger end play - serial number before 840638 | 0.10 to 0.16 | mm | 0.004 to 0.006 in |
| Clearance | Turbocharger radial clearance | 0.30 to 0.46 | mm | 0.012 to 0.018 in |
| Clearance | Valve Depth C | 0.99 MIN, 1.52 MAX | mm | |
| Clearance | Valve Head Rim Thickness | 0.79 | mm | MIN |
| Clearance | Valve Seat Grinding Depth B | 0.254 | mm | MAX |
| Clearance | Valve Seat Grinding Width | 1.5 MIN, 2.0 MAX | mm | with 60 degree stone (A) and 15 degree stone (B) |
| Clearance | Valve Seat-to-Valve Guide Concentricity | 0.05 | mm | MAX, 360 Degrees |
| Clearance | Valve Seats Grinding Cleanup Depth | 0.254 | mm | MAX |
| Clearance | Valve Spring Compression Height | 49.25 | mm | at 289.13 N MIN [65.0 lbf] / 321.16 N MAX [72.2 lbf] |
| Clearance | Valve Spring Free Length | 55.63 | mm | MIN |
| Clearance | Valve Spring Inclination | 1.0 | mm | MAX |
| Clearance | Valve Stem Diameter | 7.94 MIN, 7.98 MAX | mm | |
| Clearance | Valve depth installed | 0.99 to 1.52 | mm | 0.039 to 0.060 in |
| Clearance | Valve guide diameter | 8.019 to 8.090 | mm | 0.3157 to 0.3185 in |
| Clearance | Valve stem diameter | 7.94 to 7.98 | mm | 0.3126 to 0.3142 in |
| Clearance | Vibration damper index line misalignment (max) | 1.59 | mm [1/16 in] | |
| Clearance | Wastegate specified measurement | 0.33 to 1.3 | mm | 0.013 to 0.050 inch |
| Gap | Belt deflection at longest span | 9.5 to 12.7 | mm [3/8 to 1/2 in] | |
| Gap | Maximum allowable intake restriction - non turbo | 20 | in. H2O | 50.8 cm H2O; with dirty air filter element |
| Gap | Maximum allowable intake restriction - turbo | 25 | in. H2O | 63.5 cm H2O; with dirty air filter element |
| Other | Valve Seat Grinding Angle | Intake: 30, Exhaust: 45 | degrees | |
| Other | Wastegate actuator rod movement | 5 | mm | 0.200 in; at 200 kPa [29 psi] |
| Pressure | Charge air cooler pressure drop | 48 | kPa | 7 psi or less in 15 seconds with 207 kPa [30 psi] applied |
| Pressure | Differential Pressure to Open Bypass Valve | 138 | kPa | |
| Pressure | Filter bypass valve opening pressure | 138 | kPa | 20 psi |
| Pressure | Fuel pump gallery pressure minimum at rated RPM | 140 | kPa | 20 psi |
| Pressure | Fuel transfer pump diaphragm minimum output pressure | 21 | kPa | 3 psi |
| Pressure | Fuel transfer pump piston minimum output pressure at rated speed | 172 | kPa | 25 psi |
| Pressure | Intake manifold pressure differential maximum | 21 | kPa | 3 psi; between turbocharger outlet and intake manifold; check charge air cooler |
| Pressure | Lubricating Oil Pressure at Idle | 69 | kPa | Minimum Allowable |
| Pressure | Lubricating Oil Pressure at Rated | 207 | kPa | Minimum Allowable |
| Pressure | Lubricating oil pressure at idle (minimum allowable) | 69 | kPa [10 psi] | at idle |
| Pressure | Lubricating oil pressure at idle - minimum allowable | 69 | kPa | 10 psi; idle |
| Pressure | Lubricating oil pressure at rated (minimum allowable) | 207 | kPa [30 psi] | at rated rpm |
| Pressure | Lubricating oil pressure at rated - minimum allowable | 207 | kPa | 30 psi; rated speed |
| Pressure | Lubricating oil pressure switch actuation | 55 | kPa | 8 psi |
| Pressure | Maximum exhaust restriction - 91 EPA cert | 114.3 | mm Hg | 4.5 in Hg |
| Pressure | Maximum exhaust restriction - 94 EPA cert with oxidation catalyst | 152.6 | mm Hg | 6 in Hg |
| Pressure | Maximum exhaust restriction - non automotive | 76.2 | mm Hg | 3 in Hg |
| Pressure | Maximum fuel filter pressure drop | 35 | kPa | 5 psi |
| Pressure | Maximum fuel inlet restriction to transfer pump | 100 | mm Hg | 4 in Hg |
| Pressure | Maximum fuel return restriction | 518 | mm Hg | 20.4 in Hg |
| Pressure | Maximum inlet pressure to injection pump | 70 | kPa | 10 psi |
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
| Fluid | Grade | Standard | Ambient | Capacity | Notes |
|---|---|---|---|---|---|
| Coolant | 40% water and 60% antifreeze | below -37°C | Recommended for temperatures below -37°C [-34°F]. Never use more than 60% antifreeze. | ||
| Coolant | 50 percent ethylene-glycol base antifreeze and 50 percent water | above -37°C | Required for operation above -37°C [-34°F]. A 40 percent water / 60 percent antifreeze mixture is recommended below -37°C [-34°F]. Never use more than 60 percent antifreeze. Never use water alone. | ||
| Coolant | 50% ethylene-glycol base antifreeze and water | above -37°C | Required for operation above -37°C [-34°F]. Never use more than 60% antifreeze. Never use water alone. | ||
| Coolant | 50-percent ethylene glycol or propylene glycol antifreeze / 50-percent water | Low-silicate antifreeze meeting ASTM 4985 test (GM6038M spec.); water must not exceed 300-ppm hardness or 100 ppm chloride or sulfate | above -33°C | Never use more than 68-percent antifreeze. Drain/replace every 2 years, 320,000 km [200,000 mi], or 6000 hours. 68% EG = -63 C [-81 F]; 68% PG = -71 C [-96 F]. | |
| Engine oil | 10W-30 | below -5°C | Limited use can aid starting and provide sufficient lubricating oil flow at ambient temperatures below -5°C [23°F]; continuous use of low viscosity oils can decrease engine life. | ||
| Engine oil | 10W-30 (low-viscosity) | below -5°C | Limited use for easier starting below -5 C [23 F]; continuous use can decrease engine life | ||
| Engine oil | 5W-20 or 5W-30 (synthetic CEISG / CE/SG) | Synthetic CEISG | below -23°C | Arctic operation - ambient temperatures consistently below -23 C [-10 F] with no engine warm provisions | |
| Engine oil | SAE 15W-40 | API CE/SG (such as Cummins Premium Blue) | CC/CD or CD/SF engine oils can be used where CE oil is not available, but lubricating oil change interval must be reduced to one-half the interval given in the maintenance schedule. | ||
| Fuel | ASTM No. 2-D diesel with minimum cetane number of 40 | ASTM No. 2-D | below 0°C | Below 0 C [32 F] use a blend of No. 1-D and No. 2-D (winterized No. 2 D). Use low-sulfur fuel with cloud point at least 10 degrees below lowest expected fuel temperature. Viscosity must be kept above 1.3 centistokes at 40 C [104 F]. Do not mix gasoline, alcohol, or gasohol with diesel fuel. | |
| Fuel | No. 2 diesel fuel | cetane value 42-50 | Diesel Fuel Grade No. 1 above 0°C [32°F] can cause contamination/poor operation. |
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
⚠ To avoid engine or timing pin damage, disengage the timing pin after locating top dead center.
Tools: 1/2-inch drive, Engine Barring Tool, Part No. 3824591, Feeler Gauge, 14-mm Wrench, Flat-Blade Screwdriver or 5-mm Allen Wrench, 15 mm wrench
Tools: dial indicator, pressure gauge, regulated air pressure source
Tools: 15 mm
⚠ Do not remove the pressure cap from a hot engine. Wait until the coolant temperature is below 50 C [122 F].
⚠ Coolant is toxic. Keep away from children and pets.
⚠ Never use water alone for coolant.
Tools: Drain pan with capacity of 19 liters [5 gal]
⚠ Avoid direct contact of hot oil with your skin.
Tools: 17 mm wrench, Container able to hold at least 20 liters [15 qt]
⚠ The belt tensioner is spring loaded and must be pivoted away from the drive belt.
Tools: 3/8 inch square drive
⚠ Mechanical tightening may distort threads, damage the filter element seal or filter can.
Tools: 80 to 95 mm filter wrench, 24 mm, flat blade screwdriver
Tools: 8 mm wrench
⚠ While testing the injectors, keep hands and body parts away from the injector nozzle.
⚠ Do not bleed the fuel system on a hot engine.
Tools: 17 mm wrench, 19 mm wrench
Tools: 90-95 mm, filter wrench
⚠ Mechanical overtightening will distort threads, filter element seal, or filter can.
Tools: 75 to 80 mm and 90 to 95 mm filter wrenches
Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.
The D381036MX02 has a displacement of 3.9 liters with 4 cylinders.
The D381036MX02 powers 1 generator set(s), including Cummins/Onan 4B3.9.