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Kubota L235 Troubleshooting

The Kubota L235 is a 2WD or 4WD compact utility tractor. This model was manufactured from 1981 to 1985. The Kubota L235 is equipped with a 68 cu.in (1.1 L) Kubota D1102-A vertical 4-cycle 3-cylinder diesel engine rated at 23.5 hp (17.6 kW).

The gear transmission consists of a dry clutch and gearbox with eight forward and seven reverse gears. The maximum forward speed - 12.1 mph (19.5 km/h), max. reverse speed - 8.1 mph (13 km/h). The open center hydraulic system used a gear pump with a rated fluid flow of 6.2 gal/min (23.5 l/min).

The main relief pressure is 2250 psi (155 bar). The Kubota L235 was equipped with a manual or power assist steering system, wet disc brakes, 4.00x15 (2WD) or 9.5x24 (4WD) front tires, and 25x8.50-14 (2WD) or 16.3-16 (4WD) rear tires. The wheelbase is 66.5 inches (1680 mm) for L235 models with 2WD and 64.6 inches (1640 mm) for L235DT models with 4WD.

Engine Troubleshooting
Engine is not starting or hard starting
Fuel filter plugging - Replace the filter element
Fuel is not supplied from the tank to the system - Check the fuel shut-off valve
Water, dirt, or air in fuel system - Drain, flush, fill, and bleed system
Dirty or faulty injectors - Change fuel injectors
Faulty fuel injection pump - Install a new fuel pump or repair
Bad engine compression - Inspect cylinder block and change damaged parts
Engine stops during operation
Low coolant temperature - Warm up engine as required
Air in fuel pipes - Bleed fuel pipes
Irregular fuel injection - Adjust fuel injection timing
Fuel filter is clogged - Change filter element
Dirty or faulty injectors - Test fuel injectors and change if necessary
Diesel starts and immediately stops
Fuel injection pump timing is incorrect - Repair or replace fuel injection pump
Fuel filter is dirty - Change filter element
Fuel injector nozzles are damaged - Install a new set of well-balanced nozzles
Fuel injection pump malfunction - Rebuild or change fuel pump
Air cleaner element is clogged - Air cleaner maintenance required
Engine stalls when idle
Too low idle RPM - Normalize low idle speed
Faulty fuel injection pump - Replace or repair injection pump
Fuel injector nozzles are defective or dirty - Service or replace nozzles if required
Excessive valve clearance - Adjustment procedure required
Engine overheated
Not enough coolant - The cooling system needs to be refilled. Inspect the system for leaks
Cooling system components are damaged or system is dirty - Service the cooling system or replace faulty components
Low engine oil level - Fill the crankcase with engine oil
Worn fan belt or unadjusted belt tension - Adjust properly or replace the belt
Thermostat fault - Check thermostat, replace if necessary
Poor engine power
Fuel injectors are damaged or dirty - Check fuel injectors and replace if required
Insufficient fuel injection pressure - Correct the pressure settings
Air filter is clogged - Service or change air filter
Clogged oil filter - Replace or service engine oil filter
Diesel engine overloaded - Reduce load on the engine
Valve clearance is wrong - Check and adjust as required
Incorrect low idle setting - Normalize low idle speed
Clogged fuel hoses or pipes - Fuel hoses and pipes must be clean
Engine low compression: Valves are damaged or leaking - Valves need to be replaced
Abnormal engine knocking or noise
Timing of fuel injection pump is not adjusted - Adjust injection timing
Fuel injector nozzles are faulty - Change or clean injector nozzles
Engine oil level is insufficient - Need to add engine oil
Engine is cold - Warm up the engine as required
Main bearings or crankshaft wear - Need to install new components
Worn or broken piston rings - Have piston rings replaced
Flywheel mounting screws are loose - Tighten the screws
Diesel engine consuming too much oil
Oil leaks: Damaged gaskets or seals - Defective components must be replaced
Oil viscosity is incorrect - Fill up with the proper oil viscosity
Piston rings are seized or worn - Change the piston rings as required
Valve guides or stems are damaged - Valves need to be changed
Worn cylinder liners or pistons - Check pistons and liners, replace as required

Electrical System Troubleshooting
Battery is not charging
Battery is defective - Battery change required
Bad battery electrical wire harness - Check wires for malfunctions, repair or replace
Battery cables and terminals are corroded or loose - Service or tighten battery cables and terminals
Improper belt tension adjustment or damaged belt - Install new belt or adjust belt tension as required
Starter turns slow
Low battery voltage - Battery is drained, charge it
Battery is not holding charge - Service battery or replace it
Battery wiring harness damage - Inspect battery wiring for damage, replace or repair
Corroded or loose terminals and cables - Service or tighten battery cables and terminals
Starter motor won't turn
Battery voltage is low - Charge the battery
Discharged or faulty battery - Recharge or change battery
Faulty starter motor - Replace or repair starter
Wiring harness is disconnected or improperly connected - Check wiring harness and reconnect properly

Transmission Troubleshooting
Gear hard to shift
Misadjusted or defective clutch - Clutch needs to be replaced or adjusted
Damaged or loose gear shift linkage - Repair or change shift linkage
Damaged or worn shift forks - Shift forks need to be changed
Defective gearshift mechanism - Replace defective components
Low transmission pressure
Oil level is insufficient - Fill up the transmission oil
Plugged transmission fluid filter (if equipped) - Change or clean the transmission fluid filter
Relief valve sticking - Install a new valve
Transmission noises
Bearings are worn or cracked - Install new bearings
Not enough fluid in transmission - Fill up the transmission fluid
Dirty transmission oil - Fill up with fresh transmission oil
Damaged gears or improper backlash - Replace gears or set backlash properly
Worn or damaged shift forks - Replace the shift forks
Transmission oil leakage
Worn gaskets or seals - Change defective gaskets or seal
Cracked transmission case - Install a new transmission case

Hydraulics Troubleshooting
Hydraulic system overheats
Hydraulic system pressure is unadjusted - Adjust the pressure as required
Main relief valve is faulty or misadjusted - Adjust or replace the relief valve
Dirty hydraulic fluid - The fluid must be changed
Hydraulic system sucks air - Check the pump seals, suction pipe, and fittings
Hydraulic fluid pressure too low
Hydraulic fluid level is low - Check and refill the hydraulic fluid
Hydraulic fluid filter is clogged - Install a new hydraulic filter element
Hydraulic pump failure - Check hydraulic pump flow and replace pump if necessary
Defective or incorrect setting hydraulic control valve block - Set correctly or replace
Hydraulic cylinder is not working - Inspect cylinder components for wear or damage and change if required
Leakage in hydraulic pipes - Inspect hydraulic system for leaks and repair it
Hitch fails to lift or lifts slowly
Lack of hydraulic oil - Fill the hydraulic system with oil
Cold hydraulic oil - Warm up the oil
Hydraulic fluid filter element is dirty - Replace hydraulic filter element or service if necessary
Damaged hydraulic oil pump - Test the pump flow rate and install new pump if required
Faulty or incorrectly adjusted main relief valve - Set up or change the relief valve
Hydraulic control valve is faulty or out of adjustment - Change or adjust properly
Hydraulic cylinder is faulty - Check cylinder components for wear or damage and change if necessary
Broken or loose suction line - Retighten or change
3-point hitch lowers slowly or won't lower
Hydraulic control valve block is defective or set improper - Adjust correctly or change
Hydraulic cylinder failure - Check cylinder components for damage or wear and change if necessary
Damaged lift arm shaft - Replace the shaft
The hitch is defective if there is internal mechanical damage - Change defective or worn hitch parts
Hitch jerks when lower or lift
Hydraulic system sucks air - Inspect the pump seals, suction line, and fittings
Dirty hydraulic fluid - The fluid must be changed
Defective hydraulic pump - Check the pump capacity and replace pump if required
Defective or incorrect setting hydraulic control valve block - Change or set correctly
Hydraulic cylinder failure - Inspect the hydraulic cylinder parts for damage or wear and replace if required

Steering System Troubleshooting
Hard Steering
Steering knuckle or steering column is stuck - Inspect steering column and knuckle, replace worn parts
Steering gearbox components are worn - Replace defective components of steering gearbox
Faulty drag link or tie rod - Replace or repair
Insufficient lubrication in steering box - Need to lubricate the gearbox
Not adjusted toe-in alignment - Check and adjust toe-in
Tires are not correctly inflated - Inflate tires as necessary
Excessive steering wheel free play
Steering column bearing or shaft is worn - Change faulty parts
Steering linkage assembly is worn or loose - Repair or replace steering linkage
Worn steering gearbox bearings - Replace the bearings
Front wheel hub bearings or steering knuckles are worn - Change hub bearings or knuckles
Damaged or worn steering tie-rod ends - Change faulty part
Tractor pulls to right or left
Worn or loose steering linkage assembly - Repair or replace steering linkage
Defective steering knuckle bushing - Replace knuckle bushing
Uneven tire pressure - Inflate the tires properly
Toe-in adjustment is incorrect - Adjust toe-in correctly



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