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Kubota L2500 Troubleshooting

The Kubota L2500 standard L-series compact utility tractor was manufactured from 1998 to 2000. The Kubota L2500 driveline includes a Kubota D1403 vertical 4-cylinder liquid-cooled diesel engine and sliding gear transmission with 8 forward and 2 reverse gears.

A 85 cu.in (1.4 L) engine has a cylinder bore of 3.15" (80 mm), piston stroke of 3.64" (92.4 mm), and rated power of 27 hp (20.2 kW) at 2800 rpm. Max. travel speed (forward/reverse): 14.3 mph (22 km/h) and 9.6 mph (15.5 km/h). The open center hydraulic system used a gear pump with flow rate of 4.6 gal/min (17.4 l/min).

The hydraulic system pressure is 2250 psi (155 bar). The L2500DT (4WD) models are equipped with 7.00x15 front tyres and 11.2x24 rear tyres. The 5.00x15 front tyres and 11.2x24 rear tyres fit L2500F (2WD) tractors. The wheel base is 61.2 inches (1550 mm). The Kubota L2500 is compatible with a Kubota LA450S loader or Kubota LB400 loader with a lift capacity to maximum height of 882 lbs (400 kg), and breakout force of 1653 lbs (750 kg).

Engine Troubleshooting
Engine will not start or hard to start
Fuel filter clogging - Install new filter element
Fuel is not supplied from the tank to the system - Check the fuel shut-off valve
Air trapped in fuel system - Bleed air
Clogged or damaged injectors - Change fuel injectors
Fuel injection pump is damaged - Replacement or repair required
Engine has low compression - Inspect cylinder block and change worn parts
Engine shuts off unexpectedly during operation
Coolant temperature is low - Warm up the engine to required temperature
There is air in the fuel system - Bleed the system
Uneven fuel injections - Repair or adjustment
Fuel filter is dirty - Change filter element
Faulty or dirty injectors - Clean or replace fuel injectors
Diesel starts and stalls suddenly
Incorrect setting of fuel injection pump timing - Correct injection timing
Dirty fuel filter element - Change filter element
Clogged or damaged injector nozzles - Check and change nozzles as required
Defective fuel injection pump - Repair or install a new fuel pump
Air cleaner element clogging - Service or replace the air cleaner
Engine stops at low idle speed
Wrong adjustment of low idle speed - Correct low idle settings
Fuel injection pump malfunctioning - Replacement or repair required
Fuel injector nozzles are damaged or dirty - Service or replace nozzles if required
Valve clearance is wrong - Check and adjust
Engine overheated
Coolant level is low - Fill the radiator to the required level. Inspect the system for leaks
Cooling system is dirty or cooling parts are failed - Replace faulty parts or flush the cooling system
Engine oil level low - Need to add engine oil
Damaged fan belt or unadjusted belt tension - Adjust correctly or install new belt
Thermostat malfunction - Check and change if necessary
Diesel power loss
Fuel injectors are defective or dirty - Test fuel injectors and change if necessary
Uneven fuel injection pressure - Adjust to correct pressure
Clogged air filter - Air filter maintenance required
Dirty oil filter element - Replace or clean engine oil filter element
Diesel engine is overloaded - Shift to lower gear or reduce the load
Valve clearance is wrong - Adjust valve clearance according to specifications
Wrong adjustment of low idle speed - Correct low idle settings
Fuel pipes or hoses are dirty - Service fuel hoses and pipes
Loss of compression: Valves are broken or leaking - Valve replacement required
Engine noise or knocking
Incorrect setting of fuel injection pump timing - Fuel pump timing settings need to be corrected
Fuel injector nozzles are dirty or defective - Change injector nozzles
Insufficient engine oil - Checking oil level and add if necessary
Engine is not preheated - Warm up the engine
Worn main bearings or crankshaft - Change or repair worn components
Defective or broken piston rings - Replace piston rings
Loose flywheel screws - Check the flywheel screws and tighten as required
Excessive engine oil consumption
Oil leakage: Damaged gaskets or seals - Replace defective parts
Incorrect oil viscosity - Fill up with the correct oil viscosity
Stuck or worn piston rings - Install new piston rings
Valve stems and guides are worn - Replace defective valves
Damaged cylinder liners or pistons - Check pistons and liners, change as required

Electrical System Troubleshooting
Battery won’t charge
Faulty cell in battery - Battery replacement required
Damaged battery electrical wire harness - Inspect electrical wires for damage, change or repair
Loose or corroded battery cables and terminals - Tighten or clean cables and terminals
Belt damage or incorrect belt tension adjustment - Change belt or correctly adjust belt tension
Starter cranks slow
Low battery power - Battery is drained, recharge it
Battery discharges quickly - Service battery or change it
Damaged battery cable harness - Check electrical cables for damage, repair or replace
Corroded or loose terminals and cables - Tighten or service cables and terminals
Starter doesn't crank
Low battery power - Charge the battery
Discharged or faulty battery - Recharge or replace battery
Starter motor is faulty - Repair or change starter
Disconnected or incorrectly connected cables - Need to reconnect cables correctly

Transmission Troubleshooting
Difficulty shifting gears
Clutch is unadjusted or worn - Adjust or replace the clutch
Damaged or loose gear shift linkage - Replace or repair the shift linkage
Worn or damaged shift forks - Replace the shift forks
Faulty gear shifting mechanism - Faulty parts must be changed
Transmission fluid pressure is insufficient
Fluid level is low - Add transmission fluid as required
Transmission oil filter element is clogged (if equipped) - Replace or clean transmission oil filter
Damaged relief valve - Replace the valve
Transmission noises
Bearings are worn or cracked - Change the bearings
Oil level is insufficient - Checking transmission oil level and add if necessary
Contaminated transmission fluid - Change transmission fluid
Defective gears or incorrect backlash - Change damaged gears or adjust backlash properly
Damaged or worn shift forks - Change the shift forks
External fluid leaks
Gaskets or seals are broken - Replace worn seal or gaskets
Cracked transmission housing - Housing needs to be replaced

Hydraulics Troubleshooting
Hydraulic system is too hot
Incorrect hydraulic system pressure setting - Change the pressure settings
Unadjusted or defective main relief valve - Adjust or replace the relief valve
Contaminated hydraulic oil - Change hydraulic oil
Hydraulic system sucks air - Inspect the pump seals, suction line, and fittings
Hydraulic oil pressure is low
Not enough hydraulic oil in the system - Add oil to the hydraulic system
Hydraulic fluid filter is clogged - Replace filter element or clean if required
Hydraulic pump is faulty - Check pump performance and change it if necessary
Defective or incorrect setting hydraulic spool valve block - Adjust correctly or replace
Hydraulic cylinder is not working - Check cylinder components for wear or damage and change if necessary
Hydraulic piping leaks - Detect leaks in hydraulic system and repair it
Three-point hitch lifting is too slow or cannot be lifted
Not enough hydraulic fluid in the system - Check and refill the hydraulic fluid
Cold oil in hydraulic system - Wait for oil to warm up
Dirty hydraulic oil filter - Install a new hydraulic filter element
Faulty hydraulic oil pump - Test the pump performance and change pump if required
Defective or misadjusted main relief valve - Replace or set up the relief valve
Damaged or incorrect adjusted hydraulic spool valve - Set properly or replace
Defective hydraulic cylinder - Inspect cylinder components for wear or damage and change if required
Suction pipe is broken or loose - Tighten the pipe or replace it
3-point hitch lowers slowly or won't lower
Hydraulic spool valve is faulty or out of adjustment - Set properly or replace
Broken hydraulic cylinder - Check cylinder components for wear or damage and change if necessary
Damaged lift arm shaft - Install a new shaft
Mechanical parts of the hitch are damaged - Change faulty or worn hitch parts
3-point hitch lift or lower is jerky
Aeration in hydraulic system - Check the pump seals, suction line, and fittings
Hydraulic oil contamination - Change the oil
Damaged hydraulic oil pump - Check the pump performance and replace it if required
Hydraulic spool valve is not set properly or defective - Adjust properly or replace
Broken hydraulic cylinder - Inspect cylinder components for wear or damage and change if required

Steering System Troubleshooting
Steering wheel is hard to turn
Defective or incorrectly installed steering column - Reinstall the steering column or change it
Aeration in steering system - Bleed air
Incorrect toe-in adjustment - Check toe-in and correct
Improper tire pressure - Check the pressure and inflate tires as required
Worn steering pump - Install a new steering pump
Worn or damaged power steering valve assembly - Check and replace as required
Faulty steering box components - Replace defective parts of power steering box
Steering fluid level is low - Check fluid level and add steering fluid as required
Oil leaks in the steering system - Retighten steering hose and pipe connections
Steering wheel has too much free-play
Worn steering column coupling or shaft - Replace defective component
Damaged or worn power steering valve assembly - Inspect and replace as required
Worn steering box parts - Repair power steering box
Steering pump is faulty - Steering pump needs to be repaired or replaced
Steering tie-rod ends or linkage are worn - Change failed part
Front wheels wander to left or right
Low tire pressure - Inflate the tires
Improper toe-in - Adjust toe-in wheels properly
Faulty or worn steering tie-rod ends or linkage - Change damaged part
Faulty steering box components - Repair power steering box
Defective or worn power steering valve assembly - Replace or repair steering valve as required
Incorrectly adjusted or damaged front hub bearings - Change or adjust the bearings 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