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Kubota WG3800 Engine

General Technical Data

Kubota WG3800 Engine Specifications

Engine Model .............. Kubota WG3800
Engine Type .............. Vertical 4-cylinder liquid-cooled gasoline/LPG
Number of Cylinders .............. 4
Total Displacement, cu.in (L) .............. 229.9 (3.78)
Cylinder Bore, in (mm) ................ 3.93 (100.0)
Piston Stroke, in (mm) ................ 4.72 (120.0)
Rated Engine Power (Gas), hp (kW) ................ 87.2 (65.0)
Rated Engine Power (LPG), hp (kW) ................ 97.9 (73.0)
Rated Engine Speed, rpm ................ 2600
Maximum Speed, rpm ................ 2575-2625
Idle Speed, rpm ................ 675-725
Maximum Torque (Gas), Nm (lb-ft) ................ 250 (185)
Maximum Torque (LPG), Nm (lb-ft) ................ 290 (214)
Torque Speed (Gas), rpm ................ 1400
Torque Speed (LPG), rpm ................ 1200
Firing Order ................ 1-3-4-2
Direction of Rotation ................ Counter-clockwise (viewed from flywheel)
Lubrication System ................ Forced lubrication by trochoid pump
Cooling System ................ Forced circulation with water pump
Ignition System ................ Full transistor battery type
Starting System ................ Electric starter
Electrical System Rating, Volts ................ 12

Fuel System

Fuel System Type ................ Carburetor/Vaporizer
Carburetor Type ................ Fixed main jet
Governor Type ................ Electronic
Fuel Type ................ Gasoline (86 or higher) or Standard Commercial LP Gas

Dimensions and Weight

Overall Length, in (mm) ................ 30.9 (786)
Overall Width, in (mm) ................ 23.0 (584)
Overall Height, in (mm) ................ 31.5 (799)
Net Weight, lbs (kg) ................ 591 (268)

Kubota WG3800 Maintenance Data

Service Data

Cylinder Bore Inside Diameter (Max), in (mm) ................ 3.9626 (100.65)
Cylinder Head (Max Out of Flatness), in (mm) ................ 0.002 (0.05)
Intake Valve Clearance, in (mm) ................ 0.0071-0087 (0.18-0.22)
Exhaust Valve Clearance, in (mm) ................ 0.0071-0087 (0.18-0.22)
Fan Belt Deflection, in (mm) ................ 0.28-0.35 (7.0-9.0)

Engine Oil and Filters

Engine Oil Type (Summer) ................ SAE 30, 10W-30, 15W-40
Engine Oil Type (Winter) ................ SAE 10W-30
API Service Classifications ................ SL or higher
Oil Capacity, qts (L) ................ 12.9 (12.2)
Oil Filter Part Number ................ HH1C0-32430

Ignition System

Spark Plug Type ................ NGK IFR6F8DN
Spark Plug Gap, in (mm) ................ 0.028-0.031 (0.7-0.8)
Ignition Timing (Gas), deg ................ 14 BTDC
Ignition Timing (LPG), deg ................ 15 BTDC
Spark Plug Torque, Nm (ft-lbs) ................ 25-30 (18-21.6)

Service Intervals

Check and Adjust Spark Plug ................ Every 100 hours
Clean Air Filter Element ................ Every 100 hours
Clean Fuel Filter ................ Every 100 hours
Change Engine Oil ................ Every 500 hours
Replace Engine Oil Filter ................ Every 500 hours
Check Fan Belt Tension ................ Every 500 hours
Replace Spark Plug ................ Every 1000 hours
Replace Air Filter Element ................ Every 1000 hours
Replace Fuel Filter ................ Every 1000 hours
Check and Adjust Valve Clearance ................ Every 1000 hours
Check Vacuum Lock Hose of LPG Vaporizer ................ Every 1000 hours

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