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Kubota B3150 Troubleshooting

The Kubota B3150 is a 4WD compact utility tractor from B50 series. This model was manufactured between 2014 and 2020. The Kubota B3150 driveline includes a 91.5 cu.in (2 L) Kubota V1505 vertical 4-cylinder indirect injection water-cooled diesel engine and 3-range hydrostatic transmission with infinite forward and reverse gears.

The engine has a cylinder bore of 3.09" (78 mm), piston stroke of 3.10" (79 mm), and rated power of 28 hp (20.9 kW). Max. travel speed (forward and reverse): 11.5 mph (18.5 km/h) / 9 mph (14.5 km/h).

The open center hydraulic system used a gear pump with fluid flow rate of 8.7 gpm (33.1 lpm). The hydraulic system pressure is 161.8 bar (2347 psi). The Kubota B3150 is equipped with a hydrostatic power steering, wet disc brakes, 7.00x12 or 24x8.50-12 front tires, and 12.4x16 or 13.6x16 rear tires. The wheel base is 65.6" (1666 mm). The tractor is compatible with the following attachments: 54", 60" mid-mount 3-blade mower decks with cutting height of 1.5-4.0 in (30-100 mm), and Kubota LA534EC loader with lift capacity to full height of 1146 lbs (519 kg).

Engine Troubleshooting
Engine won't start or hard to start
Fuel filter plugging - Change filter element
Closed fuel supply valve - Open supply valve to inject fuel
Air in fuel pipes - Bleed fuel pipes
Clogged fuel injectors - Check fuel injectors and replace if required
Fuel injection pump is not working correctly - Install a new fuel pump or repair
Low compression - Check and change damaged parts
Engine shuts off unexpectedly during operation
Engine not warmed up - Warm up the engine
Water, dirt, or air in fuel system - Drain, flush, fill, and bleed system
Improper fuel injection - Fuel injection settings required
Fuel filter is clogged - Clean the filter or install new filter element
Fuel injectors are clogged or faulty - Service or change fuel injectors
Diesel starts but suddenly stops
Incorrectly set fuel injection pump timing - Check and correct adjustments
Fuel filter is clogged - Service or replace the filter
Clogged or damaged injector nozzles - Service or replace injector nozzles
Fuel injection pump malfunction - Repair or install new pump
Air cleaner is dirty - Service or replace the air cleaner
Engine stops at low idle speed
Low idle speed setting is not correct - Need to adjust idle speed
Defective fuel injection pump - Repair or change injection pump
Fuel injector nozzles are faulty - Install new set of properly balanced nozzles
Improper valve clearance - Correct valve clearance needs to be set
Engine overheats
Insufficient coolant - Fill radiator to proper level. Check system for leaks
Cooling system components are failed or system is dirty - Change faulty components or flush the cooling system
Insufficient engine oil - Checking oil level and add if necessary
Broken fan belt or incorrect belt tension - Adjust belt tension properly or replace it
Thermostat failure - Replace the thermostat
Engine lacks power
Fuel injectors are defective or dirty - Service or change fuel injectors
Improper fuel injection pressure - Adjust to correct pressure
Dirty air filter element - Change or service air filter element
Clogged oil filter element - Replace or service engine oil filter
Engine is overloaded - Reduce load or shift to lower gear
Valve clearance is not correct - Adjustment procedure required
Incorrectly adjusted low idle speed - Correct low idle settings
Restricted fuel hoses or pipes - Clean fuel pipes and hoses
Engine lost compression: Leaking or broken valves - Have valves replaced
Abnormal engine noise or knocking
Fuel injection pump timing is incorrect - Check and correct settings
Damaged or clogged injector nozzles - Test injector nozzles and replace as required
Engine oil level is low - Checking oil level and add if necessary
Engine is cold - Warm up the engine as required
Worn main bearings or crankshaft - Install new parts
Piston rings failure - Replace the piston rings as required
Flywheel mounting screws are loose - Tighten the screws
Diesel engine consuming too much oil
External oil leaks: Damaged gaskets or seals - Replace worn parts to avoid leaks
Improper oil viscosity - Use correct viscosity oil
Piston rings are stuck or worn - Piston rings replacement required
Valve guides and stems are worn - Replace defective valves
Cylinder liners or pistons are worn - Inspect liners and pistons, replace as necessary

Electrical System Troubleshooting
Battery won’t charge
Battery is defective - Battery replacement required
Damaged battery electrical wire harness - Inspect electrical wires for damage, change or repair
Loose or corroded terminals and cables - Clean or tighten cables and terminals
Incorrect belt tension adjustment or worn belt - Change belt or properly adjust belt tension
Starter turns slowly
Low battery voltage - Charge the battery
Battery is draining quickly - Service charging system or install new battery
Damaged battery electrical wire harness - Inspect electrical wires for damage, change or repair
Battery cables and terminals are loose or corroded - Clean or tighten cables and terminals
Starter doesn't crank
Low battery power - Battery is drained, recharge it
Drained or faulty battery - Recharge or change battery
Starter motor is faulty - Repair or install a new starter
Cables harness is improperly connected or disconnected - Inspect cables harness and reconnect it properly

Hydrostatic Transmission Troubleshooting
HST transmission noises
Insufficient transmission fluid level or contaminated fluid - Add the fluid to proper level or pour fresh fluid
Worn or misadjusted speed control rod linkage - Replace rod linkage or adjust correctly
Relief valve sticking - Replace relief valve
Transmission overloaded - Reduce transmission load
Damaged or worn transmission parts - Change or repair damaged parts
Hot transmission oil
Low transmission oil level - Fill the transmission housing to proper oil level
Transmission oil filter element is clogged - Change or service the transmission oil filter
Plugged or defective cooling components - Inspect all cooling components and service or change if necessary
Transmission is under excessive load - Reduce loading
Low power
Oil level is low - Fill up the transmission oil
Low charge pressure - Test charge pressure
Relief valve is worn or damaged - Replace relief valve as required
Transmission oil leaking
Broken gaskets or seals - Gaskets or seal replacement required
High pressure inside the transmission case - Inspect transmission components for wear or damage and replace if necessary
Plugged oil drain pipe - Service or change drain pipe

Hydraulics Troubleshooting
Hydraulic system overheating
Hydraulic system pressure is not set correctly - Set the hydraulic pressure as required
Misadjusted or defective main relief valve - Adjust or change relief valve
Dirty hydraulic oil - The oil must be changed
Air enters in hydraulic system - Check the pump seals, suction pipe, and fittings
Hydraulic fluid pressure is low
Lack of hydraulic oil - Fill the hydraulic system with oil
Hydraulic fluid filter element is dirty - Replace filter element or clean if required
Hydraulic pump not working - Check pump flow and install new pump if necessary
Hydraulic control valve block is defective or set improper - Change or set correctly
Faulty hydraulic cylinder - Check cylinder components for wear or damage and change if necessary
Hydraulic pipes are leaking - Identify leaks in the system and repair it
Three-point hitch lifting is too slow or cannot be lifted
Lack of hydraulic oil - Fill up the hydraulic oil
Cold hydraulic oil - Warm up the oil
Hydraulic fluid filter element clogging - Hydraulic filter maintenance required
Hydraulic pump not working - Test the pump flow rate and install new pump if required
Main relief valve malfunction or incorrect adjustment - Adjust or change relief valve
Hydraulic spool valve block is faulty or out of adjustment - Adjust correctly or replace
Hydraulic cylinder is defective - Inspect cylinder components for wear or damage and change if required
Damaged or disconnected suction pipe - Connect or replace
Three-point hitch dropping is too slow or cannot be dropped
Hydraulic control valve block is defective or set improper - Change or set correctly
Hydraulic cylinder is not working - Check cylinder components for wear or damage and change if necessary
Lift arm shaft is damaged - Install a new shaft
Internal mechanical failure of the hitch - Change defective or worn hitch parts
Hitch jerks when lower or lift
Air leaks in hydraulic system - Inspect the pump seals, suction line, and fittings
Contaminated hydraulic oil - Change hydraulic oil
Hydraulic pump failure - Flow-rate hydraulic pump and replace pump if necessary
Faulty or incorrect setting hydraulic control valve - Replace or set properly
Defective hydraulic cylinder - Inspect cylinder components for wear or damage and change if required

Steering System Troubleshooting
Steering is difficult
Steering column is worn or improperly fitted - Refit properly or change the steering column
Aeration in steering system - Bleed air from system
Incorrect toe-in - Adjust toe-in wheels properly
Tire pressure is low - Tires need to be inflated
Steering pump malfunction - Install a new steering pump
Hydrostatic steering unit is worn or defective - Inspect and replace as required
Worn or stuck relief valve - Replace or service relief valve
Steering fluid insufficient - Check and refill steering fluid
Steering system oil leakage - Retighten joints of the hydraulic steering pipes and hoses
Excessive steering wheel play
Steering column coupling or shaft is worn - Replace faulty component
Hydrostatic steering unit has wear or damage - Repair or replace the steering unit
Faulty steering pump - Repair or replace steering pump
Worn or faulty steering tie-rod ends or linkage - Replace failed component
Front wheels wander to left or right
Improper tire pressure - Check the pressure and inflate tires as required
Incorrect toe-in adjustment - Check toe-in and correct
Steering tie-rod ends or linkage are worn - Change damaged component
Hydrostatic steering unit has wear or malfunction - Change or repair steering unit if required
Steering cylinder malfunction - Change or repair steering cylinder
Incorrectly adjusted or worn front hub bearings - Replace the bearings or adjust it properly



Farm Tractors Technical Specifications
JD 1026R JD 3650 JD 6400 JD 7810
FORD 1320 FORD 2810 FORD 3930 FORD 5600
MF 250 MF 690 MF 3060 MF 6180
NH TC48DA NH M100 NH T7550 NH 8560
CASE IH 495 CASE IH 1255XL CASE IH 2140 CASE IH 2294