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Kubota D1803 Engine

General Technical Data

Kubota D1803 Engine Specifications

Engine model .......... Kubota D1803
Engine type .......... Vertical, water-cooled, 4-cycle diesel
Number of cylinders .......... 3
Bore and stroke, mm (in.) .......... 87 x 102.4 (3.43 x 4.04)
Total displacement, L (cu.in.) .......... 1.83 (111.4)
Combustion chamber .......... Spherical Type (E-TVCS)
Gross power, kw (hp) .......... 26.9 (36.1)
Net power, kw (hp) .......... 23.3 (31.2)
Maximum speed, rpm .......... 2800
Iidling speed, rpm .......... 750-850
Firing Order .......... 1-2-3
Direction of rotation .......... Counter-clockwise (viewed from flywheel side)
Compression ratio .......... 23.8
Compression Pressure .......... 2.95-3.23 MPa (427-469 psi)

Fuel System

Injection pump .......... Bosch Type mini pump
Injection pressure .......... 13.73 MPa, 1991 psi
Injection timing (Before T.D.C.) .......... 0.314 rad (18 deg)

Electrical System

Starting system .......... Cell starter (with glow plug)
Starting motor .......... 12 V, 2.0 kW
Charging generator .......... 12 V, 480 W
Recommended battery capacity .......... 12 V, 100-120 AH

Dimensions

Length, mm (in.) .......... 575.9 (22.7)
Width, mm (in.) .......... 499.0 (19.8)
Height, mm (in.) .......... 685.0 (27.0)
Dry weight, kg (lbs.) .......... 151 (332)

Kubota D1803 Maintenance Data

Fuel type .......... Diesel Fuel No.2-D
Engine oil type .......... SAE 10W-30
Engine oil capacity .......... 5.6 L (1.48 U.S.gals.)
Coolant capacity .......... 7.0 L (1.85 gals.)
Oil filter change interval .......... Every 200 hours
Fuel filter change interval .......... Every 400 hours

Kubota D1803 Service Specifications

Cylinder Head

Valve Clearance (When Cold) .......... 0.18-0.22 mm (0.0071-0.0086 in.)
Top Clearance .......... 0.60-0.70 mm (0.024-0.027 in.)
Cylinder Head Surface Flatness .......... 0.05 mm / 500 mm (0.002 in. / 19.7 in.)
Valve Recessing Recessing .......... 0.65-0.85 mm (0.026-0.033 in.)
Valve Stem to Valve Guide Clearance .......... 0.040-0.070 mm (0.0016-0.0027 in.)
Valve Timing (Intake Valve) Open .......... 0.2 rad (9°) before T.D.C.
Valve Timing (Intake Valve) Close .......... 0.68 rad (39°) after B.D.C.
Valve Timing (Exhaust Valve) Open .......... 0.72 rad (41°) before B.D.C.
Valve Timing (Exhaust Valve) Close .......... 0.2 rad (9°) after T.D.C.
Valve Spring Free Length .......... 41.7-42.2 mm (1.65-1.66 in.)
Valve Seat Angle (Intake/Exhaust) .......... 0.79 rad (45 deg)
Valve Stem to Valve Guide Clearance .......... 0.040-0.070 mm (0.0016-0.0027 in.)
Valve Timing (Intake Valve) Open .......... 0.2 rad (9 deg) before T.D.C.
Valve Timing (Intake Valve) Close .......... 0.68 rad (39 deg) after B.D.C.

Cylinder Block

Camshaft Side Clearance .......... 0.070-0.22 mm (0.0028-0.0086 in.)
Camshaft Bend .......... 0.01 mm (0.0004 in.)
Cam Height (Intake / Exhaust) .......... 33.90 mm (1.335 in.)
Camshaft Journal to Cylinder Block Bore, Oil Clearance .......... 0.050-0.091 mm (0.0020-0.0035 in.)
Camshaft Journal O.D. .......... 39.934-39.950 mm (1.5722-1.5728 in.)
Cylinder Block Bore I.D. .......... 40.000-40.025 mm (1.5748-1.5757 in.)
Rocker Arm Shaft O.D. .......... 13.973-13.984 mm (0.55012-0.55055 in.)
Rocker Arm I.D. .......... 14.000-14.018 mm (0.55119-0.55188 in.)
Rocker Arm Shaft to Rocker Arm, Oil Clearance .......... 0.016-0.045 mm (0.00063-0.0017 in.)
Push Rod Bend .......... 0.25 mm (0.0098 in.)

Timing Gear

Crank Gear to Idle Gear, Backlash .......... 0.04150-0.1122 mm (0.001634-0.004417 in.)
Idle Gear to Cam Gear, Backlash .......... 0.04150-0.1154 mm (0.001634-0.004543 in.)
Idle Gear to Fuel Supply Pump Gear, Backlash .......... 0.04150-0.1154 mm (0.001634-0.004543 in.)
Crank Gear-Oil Pump Gear, Backlash .......... 0.04150-0.1090 mm (0.001634-0.004291 in.)

Tightening Torque Specs

Injector clamp screw (M8x1.25), Nm (lb-ft) .......... 24-27 (18-20)
Cylinder head cover screw (M6x1.0), Nm (lb-ft) .......... 6.86-11.3 (5.06-8.33)
Injection pipe retaining nut (M12x1.5), Nm (lb-ft) .......... 24.5-29.4 (18.1-21.6)
Oil pressure switch screw (R1/8), Nm (lb-ft) .......... 15-19 (11-14)
Supply pump mounting nut (M8x1.25), Nm (lb-ft) .......... 24-27 (18-20)
Common rail mounting screw (M8x1.25), Nm (lb-ft) .......... 24-27 (18-20)
Coolant temperature sensor taper screw, Nm (lb-ft) .......... 16-23 (12-17)
Camshaft position sensor mounting screw, Nm (lb-ft) .......... 4-5 (3-4)
Crankshaft position sensor mounting screw, Nm (lb-ft) .......... 4-5 (3-4)
Rocker arm bracket screw (M8x1.25), Nm (lb-ft) .......... 24-27 (18-20)
Cylinder head mounting screw (M11x1.25), Nm (lb-ft) .......... 93.2-98.0 (68.8-72.3)

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