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Kubota M8950 Troubleshooting

The Kubota M8950 is a 2-wheel drive or 4-wheel drive utility tractor from M50 Series. This model was manufactured between 1984 and 1993. The Kubota M8950 tractor is powered by 262 cu.in (4.3 L) Kubota V4300-TA 4-cylinder turbocharged liquid-cooled diesel engine with a rated power of 96 hp (71.6 kW) at 2400 rpm. The tractor is fitted with a partial powershift transmission with 24 forward and 8 reverse gears. The maximum forward speed - 18.6 mph (29.9 km/h), maximum reverse speed - 6.9 mph (11.1 km/h).

The open center hydraulic system has a gear pump with a rated capacity of 11 gal/min (41.6 l/min). The hydraulic system pressure is 181 bar (2630 psi). The 2WD models are equipped with 10.0x16 front tires and 18.4x34 rear tires. The 12.4x24 front tires and 18.4x34 rear tires are used for 4WD tractors. Compatible attachments for the Kubota M8950 tractor: Kubota M1860A loader with a lift capacity to full height of 2650 lbs (1202 kg) and breakout force of 4640 lbs (2104 kg).

Engine Troubleshooting
Diesel will not start or hard to start
Dirty fuel filter element - Clean or replace the filter
Fuel supply valve is closed - Open fuel supply valve
Air in fuel lines - Bleed fuel lines
Clogged or damaged injectors - Service or change fuel injectors
Fuel injection pump is not working correctly - Change pump or rebuild it
Low compression - Inspect cylinder block and change defective components
Diesel shuts off during operation
Engine is not preheated - Warm up engine as required
Fuel lines leaking air - Tighten clamps, change faulty pipes
Irregular fuel injection - Adjust fuel injection timing
Clogged fuel filter element - Change filter element
Fuel injectors are damaged or dirty - Check fuel injectors and replace if required
Engine starts and stalls immediately
Incorrect setting of fuel injection pump timing - Fuel injection pump timing adjustment needs to be corrected
Fuel filter clogging - Change filter element
Faulty fuel injector nozzles - Test injector nozzles and replace as required
Fuel injection pump is defective - Replace injection pump or repair it
Air cleaner element clogging - Service or change air cleaner
Engine stalls at idle
Too low idle RPM - Normalize low idle speed
Fuel injection pump damage - Repair or change injection pump
Fuel injector nozzles fault - Service or replace injector nozzles
Valve clearance is out of adjustment - Adjust valve clearance according to specifications
Engine overheated
Coolant level is low - Top up coolant fluid. Check for coolant leaks
Cooling system parts are defective or system is clogged - Service the cooling system or change faulty parts
Low engine oil level - Add oil to the engine crankcase
Damaged fan belt or unadjusted belt tension - Adjust belt tension correctly or replace it
Thermostat malfunction - Replace the thermostat
Poor engine power
Clogged fuel injectors - Service or change fuel injectors
Improper fuel injection pressure - Repair or replace injection pump
Air filter element clogging - Service or change air filter
Oil filter element is dirty - Replace or clean engine oil filter element
Diesel engine is overloaded - Reduce the load or use a lower gear
Valve clearance is out of adjustment - Adjust valve clearance
Low idle speed setting is incorrect - Adjust low idle speed
Fuel pipes or hoses are dirty - Fuel hoses and pipes must be clean
Insufficient engine compression: Valves are broken or leaking - Replace the valves as required
Abnormal engine knocking or noise
Incorrectly set fuel injection pump timing - Repair or replace fuel injection pump
Damaged or clogged injector nozzles - Change or clean injector nozzles
Engine oil level is insufficient - Check oil level and add oil as required
Engine not warmed up - Warm up the engine
Main bearings or crankshaft failure - Repair or replace defective parts
Piston rings failure - Replace the piston rings as required
Flywheel bolts are loose - Bolts need to be tightened
High engine oil consumption
Oil leakage: Worn seals or gaskets - New components need to be installed
Crankcase oil too light - Use proper viscosity oil
Piston rings are defective or worn - Piston rings replacement required
Damaged valve guides or valve stems - Need to replace the valves
Cylinder liners or pistons are scored - Inspect liners and pistons, fit new parts as necessary

Electrical System Troubleshooting
Battery won’t charge
Battery dead cell - Use a new battery
Battery wiring harness damage - Inspect battery wiring for damage, replace or repair
Corroded or loose cables and terminals - Terminals and cables need to be tightened or cleaned
Belt damage or incorrect belt tension adjustment - Replace belt or correctly adjust belt tension
Starter cranks slowly
Battery voltage is low - Battery needs to be recharged
Battery is not holding charge - Service charging system or replace battery
Damaged battery electrical wire harness - Inspect electrical wires for damage, change or repair
Loose or corroded cables and terminals - Tighten or service cables and terminals
Starter motor won't turn
Low battery power - Low battery charging, charge as required
Discharged or faulty battery - Change or recharge battery
Starter motor failing - Repair or replace starter
Disconnected or incorrectly connected cables - Need to reconnect cables correctly

Transmission Troubleshooting
Difficulty shifting gears
Incorrectly adjusted or damaged clutch - Clutch replacement or adjustment required
Loose or broken gear shift linkage - Replace or repair the shift linkage
Bent or worn shift forks - Shift forks need to be replaced
Worn gear shift mechanism - Replace worn components
Low transmission oil pressure
Low transmission oil level - Check transmission oil level and add oil as required
Plugged transmission fluid filter (if equipped) - Change or clean the transmission fluid filter
Relief valve is defective - Replace valve as required
Transmission is excessively noisy
Damaged or worn bearings - Change faulty bearings
Low transmission fluid level - Fill up the transmission fluid
Transmission fluid contamination - Transmission fluid must be changed
Incorrect backlash or gears are defective - Change the gears or adjust backlash correctly
Bent or worn shift forks - Install new shift forks
Transmission oil leaks
Broken gaskets or seals - Gaskets or seal need to be replaced
Transmission housing is cracked - Replace housing or transmission assembly

Hydraulics Troubleshooting
Hydraulic system is too hot
Hydraulic system pressure is incorrect - Hydraulic pressure needs to be set correctly
Main relief valve malfunction or incorrect adjustment - Adjust relief valve or change if required
Hydraulic oil contamination - Change the oil
Air in hydraulic system - Check the pump seals, suction line, and fittings
Low hydraulic system pressure
Lack of hydraulic fluid - Need to add fluid
Hydraulic oil filter element is dirty - Clean or change hydraulic filter
Damaged hydraulic oil pump - Test pump performance and replace pump if necessary
Hydraulic control valve is faulty or out of adjustment - Adjust correctly or change
Hydraulic cylinder is not working - Inspect the hydraulic cylinder parts for damage or wear and replace if required
Leakage in hydraulic pipes - Identify leaks in the system and repair it
Three-point hitch lifting is too slow or cannot be lifted
Hydraulic oil level is low - Check oil level and add hydraulic oil as required
Cold hydraulic fluid - Warm up the fluid
Hydraulic fluid filter element is dirty - Change hydraulic filter element or clean if necessary
Hydraulic pump malfunction - Test the pump flow rate and change pump if required
Main relief valve is damaged or adjusted improperly - Adjust relief valve or change if required
Damaged or incorrect adjusted hydraulic control valve - Adjust properly or change
Hydraulic cylinder malfunction - Inspect the hydraulic cylinder components for damage or wear and change if required
Broken or disconnected suction line - Connect or replace
Hitch won't lower or lowers slowly
Hydraulic spool valve block is faulty or out of adjustment - Set correctly or replace
Hydraulic cylinder is not working - Check the hydraulic cylinder parts for damage or wear and replace if necessary
Damaged hitch cross shaft - Replace the shaft
The hitch is defective if there is internal mechanical damage - Change faulty or worn hitch components
Hitch jerks when drop or lift
Air in hydraulic system - Check the pump seals, suction pipe, and fittings
Hydraulic fluid is contaminated - Fill up with new hydraulic fluid
Hydraulic pump not working - Flow-rate hydraulic pump and replace pump if necessary
Hydraulic spool valve block is defective or set improper - Change or set correctly
Broken hydraulic cylinder - Check the hydraulic cylinder components for damage or wear and change if necessary



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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