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Kubota D1305 Engine

General Technical Data

Kubota D1305 Engine Specifications

Engine model ................ Kubota D1305
Engine type ................ 4-stroke, three-cylinder water-cooled diesel
Number of cylinders ................ 3
Total displacement, L (cu. in) ................ 1.26 (76.95)
Bore, mm (in.) ................ 78.0 (3.07)
Stroke, mm (in.) ................ 88.0 (3.46)
Gross power, kw (hp) ................ 18.5 (24.8)
Net power, kw (hp) ................ 17.9 (24.0)
Maximum speed, rpm ................ 2820
Idling speed, rpm ................ 1100
Compression ratio ................ 24:1
Firing order ................ 1-2-3
Combustion chamber ................ Spherical type
Direction of rotation ................ Counterclockwise
Lubrication system ................ Forced lubrication by trochoid pump
Oil filter ................ Full flow paper filter (cartridge type)
Cooling system ................ Pressurized radiator, forced circulation with water pump
Electrical system rating ................ 12V
Starting system ................ Electric starting with starter
Starter rating ................ 12V, 1.2kW
Starting support device ................ By glow plug in combustion chamber
Battery ................ 12V, 65AH
Charging alternator ................ 12V, 480W

Fuel System

Fuel injection pump ................ Bosch MD type
Injection nozzle ................ Mini (DNOPD)
Injection timing, deg (rad) ................ 16 (0.28) before TDC
Injection pressure, MPa (psi) ................ 13.73 (1990)
Governor ................ Mechanical type

Dimensions and Weight

Overall Length, mm (in.) ................ 497 (19.6)
Overall Width, mm (in.) ................ 396 (15.6)
Overall Height, mm (in.) ................ 590 (23.3)
Net weight, kg (lbs.) ................ 95 (209)

Kubota D1305 Maintenance Data

Cylinder Block and Valves

Cylinder bore inside diameter (maximum) ................ 78.150 mm (3.077 in)
Cylinder compression ................ 3.73-4.11 MPa (541-597 psi)
Cylinder head (max. out of flatness) ................ 0.05 mm (0.002 in)
Intake valve clearance (Cold) ................ 0.15-0.19 mm (0.006-0.008 in.)
Exhaust valve clearance (Cold) ................ 0.15-0.19 mm (0.006-0.008 in.)

Engine Oil and Filters

Engine oil type ................ SAE 10W-30, 10W-40
API service classification ................ CF, CG, or CH
Engine oil capacity, L (qts) ................ 5.7 (6.0)
Oil filter part number ................ HH150-32094
Fuel filter part number ................ 12581-43012
Air filter part number ................ 6C060-99414/32721-58242

Service Intervals

Check air filters ................ Every 100 hours
Change oil ................ Every 200 hours
Change oil filter ................ Every 200 hours
Replace fuel filter ................ Every 400 hours
Clean air filters ................ Every 400 hours
Replace fan belt ................ Every 500 hours
Check and adjust valve clearance ................ Every 800 hours
Replace air filters ................ Annually

Kubota D1305 Service Specifications

Cylinder Block

Cylinder Bore I.D. (Std) ................ 78.000-78.019 mm (3.0709-3.0716 in.)
Cylinder Bore I.D. (Oversize) ................ 78.500-78.519 mm (3.0906-3.0912 in.)
Crankshaft Alignment – 0.02 mm (0.0008 in.)
Crankshaft Journal to Bearing 1 Oil Clearance ................ 0.0340-0.119 mm (0.00134-0.00468 in.)
Crankshaft Journal to Bearing 2 Oil Clearance ................ 0.0340-0.103 mm (0.00134-0.00405 in.)
Crankshaft Journal O.D ................ 51.921-51.940 mm (2.0442-2.0448 in.)
Crankshaft Bearing 1 I.D ................ 51.974-52.040 mm (2.0463-2.0488 in.)
Crankshaft Bearing 2 I.D ................ 51.974-52.024 mm (2.0463-2.0481 in.)
Crankpin to Crankpin Bearing Oil Clearance ................ 0.029-0.091 mm (0.0012-0.0035 in.)
Crankpin O.D ................ 39.959-39.975 mm (1.5732-1.5738 in.
Crankpin Bearing I.D ................ 40.040-40.050 mm (1.5764-1.5767 in.)
Crankshaft Side Clearance (Std) ................ 0.15-0.31 mm (0.0059-0.0122 in.)
Crankshaft Side Clearance (Wear Limit) ................ 0.50 mm (0.0197 in.)
Camshaft Side Clearance ................ 0.07-0.22 mm (0.0028-0.0087 in.)
Camshaft Alignment ................ 0.01 mm (0.0004 in.)
Camshaft Journal to Cylinder Block Bore Oil Clearance ....... 0.050-0.091 mm (0.00197-0.00358 in.)

Cylinder Head and Valves

Cylinder Head Surface Flatness ................ 0.05 mm (0.002 in.)
Valve Clearance (Cold) ................ 0.145-0.185 mm (0.00571-0.00728 in.)
Top Clearance ................ 0.80-1.00 mm (0.032-0.039 in.)
Valve Stem to Valve Guide Clearance ................ 0.035-0.065 mm (0.0014-0.0025 in.)
Valve Stem O.D ................ 6.960-6.975 mm (0.2741-0.2746 in.)
Valve Guide I.D ................ 7.010-7.025 mm (0.2760-0.2765 in.)
Valve Seat Width (Intake/Exhaust) ................ 2.12 mm (0.0835 in.)
Valve Seat Angle (Intake) ................ 1.05 rad (60 deg)
Valve Seat Angle (Exhaust) ................ 0.79 rad (45 deg)
Valve Spring Free Length ................ 37.0-37.5 mm (1.46-1.47 in.)
Cam Height (Intake) ................ 28.80 mm (1.134 in.)
Cam Height (Exhaust) ................ 29.00 mm (1.142 in.)

Piston and Piston Rings

Piston Pin Bore I.D (Std) ................ 22.000-22.013 mm (0.86615-0.86665 in.)
Piston Pin Bore I.D (Wear Limit) ................ 22.03 mm (0.8673 in.)
Piston Pin O.D ................ 22.002-22.011 mm (0.86622-0.86657 in.)
Piston Pin to Small End Bushing Oil Clearance ................ 0.014-0.038 mm (0.00056-0.00150 in.)
Piston Pin Small End Bushing I.D ................ 22.025-22.040 mm (0.86713-0.86771 in.)
Second Ring Groove Clearance (Std) ................ 0.0850-0.122 mm (0.00335-0.00480 in.)
Second Ring Groove Clearance (Wear Limit) ................ 0.20 mm (0.0079 in.)
Oil Ring Groove Clearance (Std) ................ 0.02-0.06 mm (0.0008-0.002 in.)
Oil Ring Groove Clearance (Wear Limit) ................ 0.15 mm (0.0059 in.)
Top Ring End Gap (Std) ................ 0.15-0.25 mm (0.0059-0.0098 in.)
Second Ring End Gap (Std) ................ 0.40-0.55 mm (0.016-0.021 in.)
Top/Second Ring End Gap (Wear Limit) ................ 1.20 mm (0.0472 in.)
Oil Ring End Gap (Std) ................ 0.25-0.45 mm (0.0098-0.0177 in.)
Oil Ring End Gap (Wear Limit) ................ 1.25 mm (0.0492 in.)

Kubota D1305 Tightening Torque Specs

Cylinder head cover screw (M6x1.0), Nm (lb-ft) ................ 7-11 (5-8)
Cylinder head screw (M10x1.25), Nm (lb-ft) ................ 64-68 (47-50)
Injection pipe retaining nut (M12x1.5), Nm (lb-ft) ................ 25-34 (18-25)
Nozzle holder assembly (M20x1.5), Nm (lb-ft) ................ 49-69 (36-51)
Overflow pipe assembly retaining nut (M12x1.5), Nm (lb-ft) ................ 25-34 (18-25)
Glow plug (M8x1.0), Nm (lb-ft) ................ 8-14 (6-10)
Rocker arm bracket nut (M7x1.0), Nm (lb-ft) ................ 22-26 (16-19)
Fan drive pulley screw (M14x1.5), Nm (lb-ft) ................ 236-245 (174-180)
Connecting rod screw (M8x1.0), Nm (lb-ft) ................ 42-46 (31-33)
Flywheel screw (M10x1.25), Nm (lb-ft) ................ 54-58 (40-43)
Bearing case cover screw (M6x1.0), Nm (lb-ft) ................ 11-12 (8-9)
Main bearing case screw 1 (M8x1.25), Nm (lb-ft) ................ 30-34 (22-25)
Main bearing case screw 2 (M9x1.25), Nm (lb-ft) ................ 49-53 (37-39)
Alternator’s pulley nut, Nm (lb-ft) ................ 58-79 (43-58)

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