The Kubota D950-B is a 927 cc, (56.6 cu·in) natural aspirated three-cylinders four-stroke liquid-cooled internal combustion vertical diesel engine, manufactured by Kubota for general-purpose applications.
Cylinder bore and piston stroke are 75.0 mm (2.95 in) and 70.0 mm (2.76 in), respectively. Compression ratio rating is 22.0:1.
The D950-B engine produced 19.7 PS (14.5 kW; 19.5 HP) at 3,000 rpm of net (intermittent) horsepower, 21.8 PS (16.0 kW; 21.5 HP) at 3,000 rpm of gross (intermittent) horsepower and 55.6 N·m (5.7 kg·m, 41 ft·lb) at 1,800 rpm of maximum torque.
The Kubota D950-B features:
- Spherical type combustion chamber
- Bosch K-type mini fuel injection pump
- Bosch throttle type injection nozzle
- Centrifugal ball mechanical governor
- Forced lubrication by pump lubrication system
- Liquid cooling system
- Electric starter (12V, 0.8 kW)
General information
Engine Specifications | |
Engine model | D950-B |
Engine type | 4-stroke, vertical, three-cylinders |
Displacement | 927 cm3, (56.6 cu·in) |
Max. horsepower | Net (continuous): 17.3 PS (12.7 KW; 17.0 HP) at 3,000 rpm Net (intermittent): 19.7 PS (14.5 kW; 19.5 HP) at 3,000 rpm Gross (intermittent): 21.8 PS (16.0 kW; 21.5 HP) at 3,000 rpm |
Max. torque | 55.6 N·m (5.7 kg·m, 41 ft·lb) at 1,800 rpm |
Cooling system | Liquid-cooled |
Lubricating system | Forced lubrication by pump |
Combustion chamber | Spherical type |
Fuel injection pump | Bosch K Type Mini Pump |
Injection type | Indirect injection |
Injection nozzle | Bosch throttle type |
Firing order | 1-2-3 |
Fuel used | Diesel fuel No.2-D |
Starting system | Electric starter (12V, 0.8 kW) |
Starting support device | Glow plug in combustion chamber |
Governor | Centrifugal ball mechanical governor |
PTO shaft rotation | Counterclockwise (from PTO shaft side) |
Dimensions (L x W X H) | 480 x 423 x 566 mm (18.9 x 16.7 x 22.3 in) |
Dry weight | 83.1 kg (183.2 lbs) |
Cylinder Block and Head
Cylinder block | |
Compression ratio: | 22.0:1 |
Cylinder bore: | 75.0 mm (2.95 in) |
Piston stroke: | 70.0 mm (2.76 in) |
Cylinder internal diameter (standard): | 75.000-75.019 mm (2.9528-2.9535 in) |
Number of piston rings (compression / oil): | 2/1 |
Connecting rod small end diameter (standard): | 20.000-20.013 mm (0.7874-0.7879 in) |
Piston pin diameter: | 20.002-20.011 mm (0.7875-0.7878 in) |
Side clearance (Second): | 0.085-0.112 mm (0.0033-0.0044 in) |
Side clearance (Oil): | 0.020-0.055 mm (0.0008-0.0022 in) |
Ring end gap (Top): | 0.200-0.350 mm (0.0079-0.0138 in) |
Ring end gap (Second): | 0.300-0.450 mm (0.0118-0.0177 in) |
Ring end gap (Oil): | 0.250-0.400 mm (0.0098-0.0157 in) |
Ring width (Second): | 1.458-1.470 mm (0.0574-0.0579 in) |
Ring width (Oil): | 3.975-3.990 mm (0.1565-0.1571 in) |
Number of main bearings: | 4 |
Crankshaft main journal diameter: | 43.934-43.950 mm (1.7297-1.7303 in) |
Crankpin journal diameter: | 36.959-36.975 mm (1.4551-1.4557 in) |
Cylinder head | |
Valves: | 2,(6 valves in total) |
Valve timing (INTAKE): | Open: 20° Before T.D.C. Close: 45° After B.D.C. |
Valve timing (EXHAUST): | Open: 50° Before B.D.C. Close: 15° After T.D.C. |
Valve seat width (INTAKE): | 2.120 mm (0.0835 in) |
Valve seat width (EXHAUST): | 2.120 mm (0.0835 in) |
Value seat angle (INTAKE): | 45° |
Value seat angle (EXHAUST): | 45° |
Valveface angle (INTAKE): | 45.5° |
Valveface angle (EXHAUST): | 45.5° |
Valve steam diameter (INTAKE): | 6.960-6.975 mm (0.274-0.2746 in) |
Valve steam diameter (EXHAUST): | 6.960-6.975 mm (0.274-0.2746 in) |
Valve spring free length (INTAKE): | 35.100-34.800 mm (1.3819-1.3701 in) |
Valve spring free length (EXHAUST): | 35.100-34.800 mm (1.3819-1.3701 in) |
Camshaft lobe height (INTAKE): | 26.880 mm (1.0583 in) |
Camshaft lobe height (EXHAUST): | 26.880 mm (1.0583 in) |
Camshaft journal diameter : | 32.934-32.950 mm (1.2966-1.2972 in) |
Tightening torque
Tightening torque specs | |
Head cover cap nuts (M7x1.0): | 6.9-8.8 Nm (0.7-0.9 kgf-m, 5.1-6.5 lb-ft) |
Head screws and nuts (M9x1.25): | 64.7-69.6 Nm (6.6-7.1 kgf-m, 47.7-51.4 lb-ft) |
Main bearing case screw 1 (M7x1.0): | Flange bolts 26.5-30.4 Nm (2.7-3.1 kgf-m, 19.5-22.4 lb-ft) Non-flange bolt 19.6-23.5 Nm (2.0-2.4 kgf-m, 14.5-17.4 lb-ft) |
Main bearing case screw 2 (M8x1.25): | 29.4-34.3 Nm (3.0-3.5 kgf-m, 21.7-25.3 lb-ft) |
Flywheel screw (M10x1.25): | Flange bolts 58.8-63.7 Nm (6.0-6.5 kgf-m, 43.4-47.0 lb-ft) Non-flange bolt 53.9-58.8 Nm (5.5-6.0 kgf-m, 39.8-43.4 lb-ft) |
Connecting rod screw (M7x0.75): | 26.5-30.4 Nm (2.7-3.1 kgf-m, 19.5-22.4 lb-ft) |
Rocker arm bracket nuts (M7x1.0): | 16.7-20.6 Nm (1.7-2.1 kgf-m, 12.3-5.2 lb-ft) |
Idle gear shaft screws (M6x1.0): | 9.8-11.3 Nm (1.00-1.15 kgf-m, 7.2-8.3 lb-ft) |
Idle gear shaft screws (M6x1.0): | 9.8-11.3 Nm (1.00-1.15 kgf-m, 7.2-8.3 lb-ft) |
Glow plugs (M10x1.25): | 19.6-24.5 Nm (2.0-2.5 kgf-m, 14.5-18.1 lb-ft) |
Drain plug (M11x1.25): | 39.2-49.0 Nm (4.0-5.0 kgf-m, 28.9-36.2 lb-ft) |
Nozzle holder assembly (M24x2.0): | 29.4-49.0 Nm (3.0-5.0 kgf-m, 21.7-36.2 lb-ft) |
Nozzle holder and nozzle retaining nut: | 58.8-78.5 Nm (6.0-8.0 kgf-m, 43.4-57.9 lb-ft) |
Nozzle holder mounting screw (M24x2.0): | 39.2-49.0 Nm (4.0-5.0 kgf-m, 28.9-36.2 lb-ft) |
Crankshaft nut (M24x1.5): | 137.3-156.9 Nm (14.0-16.0 kgf-m, 101.3-115.7 lb-ft) |
Service Data
Engine | |
Maximum speed: | 3,200 rpm |
Idle speed: | 800 rpm |
Cylinder compression: | 31.5 kgf/cm2 (3.09 MPa, 448 psi) |
Compression differential limit between cylinders: | 10% or less |
Valve clearance | |
Intake valve clearance: | 0.145-0.185 mm (0.0057-0.0073 in) |
Exhaust valve clearance: | 0.145-0.185 mm (0.0057-0.0073 in) |
Oil system | |
Lubrication system: | Forced lubrication by pump |
Oil type: | API CC or better |
Oil capacity: | 4.6 L (4.86 US. qt, 4.05 Imp. qt.) |
Oil filter: | Full flow paper filter (cartridge type) |
Oil pressure: | At idle spped: 68 kPa (0.7 kgf/cm2, 10 psi) At rated speed: 196-441 kPa (2.0-4.5 kgf/cm2, 29-64 psi) |
Fuel system | |
Fuel injection pump | Bosch K Type Mini Pump |
Injection nozzle | Bosch throttle Type |
Injection timing: | 20° B.T.D.C. |
Fuel injection pressure | 13.73-14.71 MPa (140-150 kgf/cm2, 1991-2133 psi) |
Cooling system | |
Type: | Pressurized radiator, forced circulation with water pump (not included in the basic engine) |
Thermostat’s valve opening temperature: | 80.5-83.5°C (176.9-182.3°F) |
Temperature at which thermostat completely opens: | 95°C (203°F) |
Coolant capacity | 4.6 L (4.9 US. qt, 4.0 Imp. qt.) |
Electrical system | |
Battery: | 12V, 65AH or equivalent |
Starter mica undercut: | 0.5-0.8 mm (0.0197-0.0315 in) |
Starter brush length: | 16.0 mm (0.6299 in) |
Alternator (no-load voltage): | AC 20V |
Glow plug resistance: | 1.0-1.2 Ω |
We try to use official documentation and verify the published data, but errors may occur. In addition, specifications of machinery and equipment may vary depending on markets and modifications. We do not recommend the use of this data for spare parts or repairs. Use official service manuals or parts catalogs for your product.
Be the first to comment