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Kubota D905 Engine

General Technical Data

Kubota D905 Engine Specifications

Engine Model .......... Kubota D905
Engine Type .......... Vertical, water-cooled, 4-cycle diesel
Number of cylinders .......... Three
Bore, mm (in.) .......... 72.0 (2.83)
Stroke, mm (in.) .......... 73.6 (2.90)
Total displacement, cm3 (cu. in.) .......... 898 (54.86)
Gross power, kw (hp) .......... 19.4 (26.0)
Net power, kw (hp) .......... 17.5 (23.5)
Maximum speed, rpm .......... 3800
Idling speed, rpm .......... 600
Maximum torque, Nm (lb-ft) .......... 52.8 (38.9)
Torque speed, rpm .......... 2400
Combustion Chamber .......... Spherical type
Direction of rotation .......... Counter-clockwise
Compression ratio .......... 22:1
Firing order .......... 1-2-3

Fuel System

Fuel injection pump .......... Bosch MD type mini pump
Injection nozzle .......... Mini nozzle (DNOPD)
Injection timing (Without timer), deg (rad) .......... 21-23 (0.37-0.40) before T.D.C.
Injection timing (With timer), deg (rad) .......... 9-11 (0.16-0.19) before T.D.C.
Injection pressure, MPa (psi) .......... 13.73 (1991)
Governor .......... Centrifugal mechanical governor

Lubricating System

Lubricating system .......... Forced lubrication by pump
Oil pressure indicating .......... Electrical type switch
Oil filter .......... Full flow paper filter (cartridge type)

Electrical System

Starting system .......... Electric starting with starter
Starter Rating .......... 12V, 0.9 kW
Starting support device .......... By glow plug in combustion chamber
Battery .......... 12V, 65 AH, equivalent
Dynamo for charging .......... 12V, 150W

Dimensions

Length, mm (in.) .......... 497.8 (19.60)
Width, mm (in.) .......... 396 (15.59)
Height, mm (in.) .......... 608.7 (23.96)
Dry weight, kg (lbs.) .......... 93.0 (205.0)

Kubota D905 Maintenance Data

Fuel type .......... Diesel fuel No. 2-D
Engine oil type .......... SAE 10W-40
Engine oil capacity, L (qts) .......... 4.0 (4.23)
Coolant capacity, L (qts) .......... 3.4 (3.6)
Oil filter change interval .......... Every 200 hours
Oil change interval .......... Every 200 hours
Fuel filter change interval .......... Every 400 hours
Fan belt tension (Deflection) .......... 7-9 mm (0.28-0.35 in.)

Kubota D905 Service Specifications

Cylinder Liner

Cylinder Liner I.D. .......... 72.000-72.019 mm (2.8346-2.8354 in.)
Oversized Cylinder Liner I.D. - + 0.5 mm (+ 0.0197 in.)

Cylinder Head

Cylinder Head Surface Flatness .......... 0.05 mm (0.0019 in.)
Top Clearance .......... 0.55-0.75 mm (0.0217-0.0295 in.)
Compression Pressure .......... 2.84-3.23 MPa (412-469 psi)
Variance Among Cylinders .......... 10 % or less

Valves

Valve Clearance (Cold) .......... 0.145-0.185 mm (0.0057-0.0072 in.)
Valve Seat Width (Intake/Exhaust) .......... 2.12 mm (0.0835 in.)
Valve Seat Angle (Intake) .......... 1.047 rad. (60°)
Valve Seat Angle (Exhaust) .......... 0.785 rad. (45°)
Valve Face Angle (Intake) .......... 1.047 rad. (60°)
Valve Face Angle (Exhaust) .......... 0.785 rad. (45°)
Valve Recessing .......... 0.05-0.25 mm (0.0020-0.0060 in.)
Clearance between Valve Stem and Valve Guide .......... 0.035-0.065 mm (0.0014-0.0025 in.)

Valve Timing

Intake Valve, Open .......... 0.24 rad. (14°) before T.D.C.
Intake Valve, Close .......... 0.52 rad. (30°) after B.D.C.
Exhaust Valve, Open .......... 0.96 rad. (55°) before B.D.C.
Exhaust Valve, Close .......... 0.24 rad. (14°) after T.D.C.

Camshaft

Camshaft Side Clearance .......... 0.07-0.22 mm (0.0028-0.0087 in.)
Camshaft Alignment .......... 0.01 mm (0.0004 in.)
Cam Height (Intake) .......... 28.80 mm (1.1339 in.)
Cam Height (Exhaust) .......... 29.00 mm (1.1417 in.)

Timing Gear Backlash

Idle Gear 1 to Cam Gear .......... 0.036-0.114 mm (0.0014-0.0045 in.)
Idle Gear 1 to Injection Pump Gear .......... 0.034-0.116 mm (0.0013-0.0046 in.)
Clearance between Idle Gear Shaft and Idle Gear Bushing Idle Gear 1 ........ 0.020-0.054 mm (0.0008-0.0021 in)
Idle Gear Bushing I.D. .......... 26.000-26.021 mm (1.0236-1.0244 in.)
Idle Gear Shaft 1 O.D. .......... 25.967-25.980 mm (1.0223-1.0228 in.)
Clearance between Idle Gear Shaft and Idle Gear Bushing Idle Gear 2 ........ 0.020-0.054 mm (0.0008-0.0021 in)
Idle Gear Bushing I.D. .......... 26.000-26.021 mm (1.0236-1.0244 in.)
Idle Gear Shaft 2 O.D. .......... 25.967-25.980 mm (1.0223-1.0228 in.)

Piston / Piston Ring

Piston Pin Bore .......... 22.000-22.013 mm (0.8661-0.8687 in.)
Clearance between Compression Ring 2 and Ring Groove .......... 0.085-0.112 mm (0.0033-0.0044 in.)
Clerance between Oil Ring and Ring Groove .......... 0.020-0.055 mm (0.0008-0.0021 in.)
Ring Gap (Compression Ring 1) .......... 0.25-0.40 mm (0.0098-0.0157 in.)
Ring Gap (Compression Ring 2) .......... 0.25-0.40 mm (0.0098-0.0157 in.)
Ring Gap (Oil Ring) .......... 0.25-0.40 mm (0.0098-0.0157 in.)

Connecting Rod

Connecting Rod Alignment .......... 0.05 mm (0.0020 in.)
Clearance between Piston Pin and Small end Bushing .......... 0.014-0.038 mm (0.0006-0.0015 in.)
Piston Pin O.D. .......... 22.002-22.011 mm (0.8662-0.8666 in.)
Small End Bushing I.D. .......... 22.025-22.040 mm (0.8671-0.8677 in.)

Crankshaft

Oil Clearance between Crankshaft and Crankshaft Bearing 1 .......... 0.034-0.114 mm (0.0013-0.0045 in.)
Crankshaft O.D. .......... 47.934-47.950 mm (1.8872-1.8878 in.)
Crankshaft Bearing 1 I.D. .......... 47.984-48.084 mm (1.8891-1.8917 in.)
Oil Clearance between Crankshaft and Crankshaft Bearing 2 .......... 0.034-0.095 mm (0.0013-0.0037 in.)
Crankshaft O.D. .......... 47.934-47.950 mm (1.8872-1.8878 in.)
Crankshaft Bearing 2 I.D. .......... 47.984-48.029 mm (1.8891-1.8909 in.)
Oil Clearance between Crankshaft and Crankshaft Bearing 3 .......... 0.034-0.098 mm (0.0013-0.0039 in.)
Crankshaft O.D. .......... 51.921-51.940 mm (2.0441-2.0449 in.)
Crank bearing 3 I.D. .......... 51.974-52.019 mm (2.0462-2.0480 in.)
Oil Clearance between Crank Pin and Crank Pin Bearing .......... 0.029-0.091 mm (0.0011-0.0036 in.)

Tightening Torque Specs

Cylinder head cover screw (M7x1.0), Nm (lb-ft) .......... 6.9-8.8 (5.1-6.5)
Cylinder head screw (M10x1.25), Nm (lb-ft) .......... 63.7-68.6 (47.0-50.6)
Main bearing case screw 1 (M8x1.25), Nm (lb-ft) .......... 29.4-34.3 (21.7-25.3)
Main bearing case screw 2 (M9x1.25), Nm (lb-ft) .......... 49.0-53.9 (36.2-39.8)
Flywheel screw (M10x1.25), Nm (lb-ft) .......... 53.9-58.8 (39.8-43.4)
Connecting rod screw (M8x1.0), Nm (lb-ft) .......... 41.2-46.1 (30.4-34.0)
Rocker arm bracket nuts (M7x1.0), Nm (lb-ft) .......... 21.6-26.5 (15.9-19.5)

KUBOTA TRACTORS TROUBLESHOOTING
L235	L2501	L2550	L275	L3110
L3301	L35	L3710	L3901	L4310
L5030	M4700	M5700	M6040	M6800
M8200	M8540	M9000	MX5100	MX5200