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Kubota L4701 Troubleshooting

The Kubota L4701 compact utility tractor was manufactured from 2014 to 2021. This model was designed in 2 versions: L4701F (2WD) and L4701DT (4WD). The Kubota L4701 driveline consists of a 148.5 cu.in (2.43 L) Kubota V2403-CR-E4 4-cycle vertical 4-cylinder direct injection water-cooled diesel engine with a rated power of 47.3 Hp (35.2 kW), and Synchro-Shuttle transmission with 8 forward and 8 reverse gears.

Max forward speed - 14.9 mph (24.1 km/h), maximum reverse speed - 14.3 mph (23.1 km/h). The open center hydraulic system includes a gear pump with fluid flow rate of 7.8 gallons per minute (29.5 liters per minute). The hydraulic pressure is 177 bar (2560 psi). The 2-wheel drive models are equipped with 7.5Lx15 front tires and 14.9x24 rear tires. The 8.3x16 front tires and 14.9x24 rear tires are used for tractors with 4-wheel drive.

The wheel base is 72.8" (1850 mm) for 4x2 (2WD) models and 72.6" (1845 mm) for 4x4 (4WD) models. Compatible attachments for the tractor: Kubota LA765 front-end loader with a maximum lift height of 105.2" (2670 mm), and Kubota BH92 backhoe with 2-ft flat digging depth of 106.1" (2690 mm).

Engine Troubleshooting
Engine won't start or hard to start
Fuel filter is clogged - Clean or change the filter
The fuel shut-off valve is closed - Open fuel shut-off valve
Air in fuel system - Air-bleed fuel system
Faulty or dirty injectors - Clean or replace fuel injectors
Fuel injection pump malfunction - Change pump or rebuild it
Bad engine compression - Check cylinder block and replace worn parts
Engine stalls while running
Engine is not fully warmed up - Warm up to required temperature
Water, dirt, or air in fuel system - Drain, flush, fill, and bleed system
Uneven fuel injections - Repair or adjustment
Clogged fuel filter element - Replace the filter element
Fuel injectors are damaged or dirty - Test fuel injectors and change if necessary
Engine starts and stops
Timing of fuel injection pump is not adjusted - Fuel injection pump timing adjustment needs to be corrected
Clogged fuel filter element - Change filter element
Dirty or defective injector nozzles - Service or replace nozzles if required
Fuel injection pump malfunction - Replace or rebuild injection pump
Dirty air cleaner element - Install new cleaner element or replace it
Engine stops when idle
Low idle speed setting is incorrect - Adjust as required
Faulty fuel injection pump - Install a new pump or rebuild
Fuel injector nozzles are faulty - Change injector nozzles
Excessive valve clearance - Check and adjust
Engine overheats
Lack of coolant in cooling system - Fill radiator to proper level. Check system for leaks
Cooling system parts are defective or system is clogged - Change faulty components or flush the cooling system
Insufficient engine oil - Check and refill engine oil
Worn fan belt or improper belt tension - Adjust belt tension correctly or change it
Thermostat malfunction - Check and replace if required
Low engine power
Clogged or damaged injectors - Clean or replace fuel injectors
Insufficient fuel injection pressure - Adjust to correct pressure
Air filter is clogged - Service or change air filter
Clogged oil filter - Replace or service engine oil filter
Engine overload - Reduce engine load
Valve out of adjustment - Have it adjusted
Incorrectly set low idle speed - Correct low idle adjustment
Fuel pipes or hoses clogging - Clean fuel hoses and pipes
Insufficient engine compression: Valves are faulty or leaking - Replace the valves
Abnormal engine noise or knocking
Incorrect setting of fuel injection pump timing - Check and correct adjustments
Dirty or defective injector nozzles - Test injector nozzles and replace as required
Engine oil level is low - Fill up the oil to required level
Coolant temperature is low - Warm up engine as required
Crankshaft or main bearings wear - Change defective components as required
Stuck or worn piston rings - Have piston rings replaced
Loose flywheel screws - Inspect the flywheel screws and tighten securely
Engine using too much oil
Oil leaking: Damaged gaskets or seals - Replace worn parts to avoid leaks
Improper oil viscosity - Fill up with the proper oil viscosity
Damaged or seized piston rings - Have piston rings replaced
Valve stems and guides are worn - Valves need to be changed
Damaged cylinder liners or pistons - Inspect liners and pistons, replace as necessary

Electrical System Troubleshooting
Battery won’t charge
Battery is defective - Use a new battery
Battery wiring harness damage - Inspect battery wiring for damage, replace or repair
Loose or corroded cables and terminals - Service or tighten battery terminals and cables
Improper belt tension adjustment or damaged belt - Adjust belt tension properly or change belt
Starter cranks slow
Low battery output - Charge the battery
Battery discharges quickly - Service or change the battery
Battery electrical wire harness failure - Inspect wires for defects, change or repair
Loose or corroded terminals and cables - Tighten or clean terminals and cables
Starter motor won't turn
Battery voltage is low - Battery is drained, recharge it
Discharged or worn battery - Charge or change the battery
Starter motor failure - Starter should be changed
Improperly connected or disconnected cables - Check battery cables and connect properly

Transmission Troubleshooting
Gears are hard to shift
Misadjusted or defective clutch - Adjust correctly or replace
Gear shift linkage is loose or broken - Replace or repair the shift linkage
Worn or damaged shift forks - Replace defective shift forks
Defective gearshift mechanism - Replace defective components
Insufficient transmission fluid pressure
Insufficient oil supply - Fill up the transmission oil
Clogged transmission oil filter (if equipped) - Change or clean the transmission oil filter
Relief valve is defective - Install a new relief valve
Transmission is making noise
Cracked or worn bearings - Faulty bearings should be changed
Low transmission fluid level - Fill the transmission housing with fluid
Contaminated transmission fluid - Fill up with fresh transmission fluid
Improper backlash or damaged gears - Replace gears or adjust backlash properly
Shift forks are worn or damaged - Install new shift forks
Transmission fluid leaking
Gaskets or seals are defective Gaskets or seal replacement required
Cracked transmission housing - Housing needs to be replaced

Hydraulics Troubleshooting
Hydraulic system is too hot
Incorrect pressure in hydraulic system - Changing the system pressure
Main relief valve malfunction or incorrect adjustment - Adjust relief valve or change if required
Contaminated hydraulic oil - Change hydraulic oil
Hydraulic system sucks air - Inspect the pump seals, suction pipe, and fittings
Low hydraulic oil pressure
Hydraulic fluid level is low - Check and refill the hydraulic fluid
Hydraulic fluid filter element is dirty - Replace hydraulic filter element or service if necessary
Hydraulic pump failure - Check the pump performance and replace it if required
Damaged or incorrect adjusted hydraulic control valve - Set correctly or replace
Hydraulic cylinder malfunction - Check cylinder components for damage or wear and change if necessary
Leakage in hydraulic lines - Identify leaks in the system and repair it
Hitch fails to lift or lifts slowly
Lack of hydraulic fluid - Need to add fluid
Hydraulic fluid is too cold - Allow fluid to warm
Hydraulic oil filter element clogging - Clean the hydraulic filter element or replace if necessary
Defective hydraulic pump - Check pump flow and change pump if necessary
Unadjusted or defective main relief valve - Adjust relief valve or change if required
Hydraulic control valve block is not set properly or defective - Change or adjust correctly
Faulty hydraulic cylinder - Check cylinder components for wear or damage and change if necessary
Damaged or disconnected hydraulic suction pipe - Connect or replace the pipe
3-point hitch fails to drop or drops slowly
Damaged or incorrect adjusted hydraulic control valve - Replace or set properly
Hydraulic cylinder is not working - Check cylinder components for damage or wear and change if necessary
Hitch rock shaft is worn Replace the shaft
Damaged mechanical components of the hitch - Replace worn or faulty hitch components
Hitch lowering or lifting is not smoothly
Air leaks in hydraulic system - Inspect the pump seals, suction pipe, and fittings
Dirty hydraulic oil - The oil must be changed
Damaged hydraulic oil pump - Check the pump performance and replace it if required
Hydraulic spool valve block is defective or set improper - Adjust properly or change
Hydraulic cylinder is faulty - Check cylinder components for wear or damage and change if necessary

Steering System Troubleshooting
Steering is stiff
Steering column is damaged or improperly mounted - Replace the steering column or mount it properly
Aeration in steering system - Bleed air
Not adjusted toe-in - Check and adjust toe-in
Tire pressure is not correct - Check tire pressure and inflate as required
Faulty steering pump - Check the hydraulic steering pump and change if necessary
Damaged or worn hydrostatic steering unit - Inspect and replace as required
Relief valve malfunction or sticking - Check relief valve and change if required
Lack of steering oil - Fill the steering system with oil
Oil leaks in the steering system - Tighten connections of hydraulic hoses and pipes in steering system
Excessive play in steering
Steering column coupling or shaft is extremely worn out - Replace faulty part
Worn or damaged hydrostatic steering unit - Inspect and change as required
Hydraulic steering pump is defective - Repair or replace steering pump
Faulty or worn steering linkage or tie-rod ends - Change failed part
Tractor is pulling to left or right
Front tires are worn out - Install new tires
Toe-in adjustment is incorrect - Adjust toe-in correctly
Steering tie-rod ends or linkage are defective - Change failed part
Hydrostatic steering unit is damaged or worn - Change or repair steering unit if required
Damaged steering cylinder - Repair or change hydraulic steering cylinder
Front hub bearings are incorrectly adjusted or worn - Replace the bearings or adjust it properly



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JD 1026R JD 3650 JD 6400 JD 7810
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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