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Kubota D1703 Engine

General Technical Data

Kubota D1703 Engine Specifications

Engine model .......... Kubota D1703
Engine type .......... Vertical, water-cooled, 4-cycle diesel
Number of cylinders .......... 3
Bore and stroke, mm (in.) .......... 87 x 92.4 (3.43 x 3.64)
Total displacement, L (cu.in.) .......... 1.65 (100.5)
Combustion chamber .......... Spherical Type (E-TVCS)
Gross power, kw (hp) .......... 25.7 (34.5)
Net power, kw (hp) .......... 22.4 (30.0)
Maximum speed, rpm .......... 3000
Iidling speed, rpm .......... 750-850
Firing Order .......... 1-2-3
Direction of rotation .......... Counter-clockwise (viewed from flywheel side)
Compression ratio .......... 22.6
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 .......... 12V, 1.4 kW
Charging generator .......... 12V, 480W
Battery capacity .......... 12V, 70-80 AH

Dimensions

Length, mm (in.) .......... 572.3 (22.6)
Width, mm (in.) .......... 507.3 (20.2)
Height, mm (in.) .......... 643.5 (25.4)
Dry weight, kg (lbs.) .......... 149 (329)

Kubota D1703 Maintenance Data

Fuel type .......... Diesel Fuel No.2-D
Engine oil type .......... SAE 10W-30
Engine oil capacity .......... 5.61 L (1.49 gals.)
Coolant capacity .......... 5.52 L (1.46 gals.)
Oil filter change interval .......... Every 150 hours
Fuel filter change interval .......... Every 300 hours
Fan belt tension .......... 7-9 mm (0.28-0.35 in.)

Kubota D1703 Service Specifications

Cylinder Block

Cylinder Bore (Oversize) I.D. .......... 87.250-87.272 mm (3.4351-3.4359 in.)
Cylinder Maximum I.D. to Cylinder Minimum I.D. (Difference) .......... 0.15 mm (0.0059 in.)
Cylinder Block Bore I.D. .......... 40.000-40.025 mm (1.5748-1.5757 in.)
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.)
Piston Pin Bore I.D. .......... 25.000-25.013 mm 0.98426-(0.98476 in.)
Top Ring to Ring Groove Clearance .......... 0.050-0.090 mm (0.0020-0.0035 in.)
Top Ring (Ring Gap) .......... 0.20-0.35 mm (0.0079-0.013 in.)
Piston Pin O.D. .......... 25.004-25.011 mm (0.98441-0.98468 in.)
Second Ring (Ring Gap) .......... 0.30-0.45 mm (0.012-0.017 in.)
Oil Ring (Ring Gap) .......... 0.20-0.40 mm (0.0079-0.015 in.)
Connecting Rod Alignment .......... 0.05 mm (0.002 in.)
Piston Pin to Small End Bushing, Oil Clearance .......... 0.014-0.036 mm (0.00056-0.0014 in.)
Crankpin O.D. .......... 46.959-46.975 mm (1.8488-1.8494 in.)
Crankpin Bearing I.D. .......... 47.000-47.046 mm (1.8504-1.8522 in.)
Crankshaft Side Clearance .......... 0.15-0.31 mm (0.0059-0.012 in.)

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 Spring (Setting Load / Setting Length) .......... 118 N / 35.0 mm (26.5 lbf / 1.38 in.)
Valve Spring Tilt .......... 1.0 mm (0.039 in.)
Valve Seat Width (Intake/Exhaust) .......... 2.12 mm (0.0835 in.)
Valve Seat Angle (Intake/Exhaust) .......... 0.79 rad (45 deg)
Valve Stem-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.
Valve Timing (Exhaust Valve) Open .......... 0.72 rad (41 deg) before B.D.C.
Valve Timing (Exhaust Valve) Close .......... 0.2 rad (9 deg) after T.D.C.

Tightening Torque Specs

Cylinder head mounting screw (M11x1.25), Nm (lb-ft) .......... 93.2-98.0 (68.8-72.3)
Oil cooler joint screw (M20x1.5), Nm (lb-ft) .......... 40-44 (29-32)
Fan drive pulley mounting nut (M30x1.5), Nm (lb-ft) .......... 138-156 (102-115)
Camshaft set 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)
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)
Boost sensor mounting screw (M4x0.7), Nm (lb-ft) .......... 0.98-1.7 (0.73-1.3)
Glow lead mounting nut (M4x0.7), Nm (lb-ft) .......... 0.98-1.7 (0.73-1.3)
Glow plug (M10x1.25), Nm (lb-ft) .......... 15-19 (11-14)
Injector clamp bolt (M8x1.25), Nm (lb-ft) .......... 23.5-27.5 (17.4-20.2)
Injection pipe cap nut (M12x1.5), Nm (lb-ft) .......... 24.5-29.4 (18.1-21.6)
Mounting screw of bearing case cover (M8x1.25), Nm (lb-ft) .......... 24-27 (18-20)

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