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John Deere 6400 Troubleshooting

The John Deere 6400 is a 4WD (4x4) farm tractor. This model was manufactured from 1992 to 1998. The JD 6400 tractor is powered by 276 cu.in (4.5 L) John Deere 4045TL four-cylinder turbocharged diesel engine with a rated power of 100 hp (74.6 kW) and 404 Nm (298 lb-ft) of peak torque at 1540 rpm.

The John Deere 6400 tractor is equipped with 4 types of transmission. Type 1: 12x4 SyncroPlus fully synchronized transmission. Type 2: 15x5 SyncroPlus fully synchronized transmission. Type 3: 16x16 PowrQuad partial power shift transmission. Type 4: 20x20 PowrQuad partial power shift transmission.

Max. forward speed - 18.7 mph (30.1 km/h), maximum reverse speed - 18.6 mph (29.9 km/h). The closed center pressure-flow compensating hydraulic system includes a variable displacement pump with fluid flow rate of 15.9 gal/min (60 l/min). The main relief pressure is 2900 psi (200 bar). The tractor is fitted with 13.6x28 front tires and 16.9x38 rear tires. The wheelbase is 94.5 in (2400 mm).

The JD 6400 tractor can be equipped with the following attachments: John Deere 620 loader with lift capacity to max height of 2707 lbs (1227 kg), and John Deere 640 SL loader with lift capacity to max height of 3243 lbs (1471 kg).

Engine Troubleshooting
Engine doesn't start or starts hard
Dirty fuel filter element - Service the filter
Closed fuel cock - Open fuel on-off cock to inject fuel
Air in fuel lines - Bleed fuel lines
Dirty or faulty injectors - Test fuel injectors and change if necessary
Fuel injection pump damage - Rebuild or install a new injection pump
Poor cylinder compression - Inspect and replace faulty parts
Engine stops during operation
Low coolant temperature - Warm up the engine
Fuel-line is leaking air - Retighten clamps, replace defective pipes
Uneven fuel injections - Repair or adjustment
Fuel filter is clogged - Change filter element
Fuel injectors are defective or dirty - Check fuel injectors and replace if required
Engine starts and stalls immediately
Fuel injection pump out of timing - Correct injection timing
Clogged fuel filter element - Change the filter element
Fuel injector nozzles are damaged or dirty - Test injector nozzles and replace as required
Fuel injection pump malfunction - Install a new fuel pump or repair
Air cleaner clogging - Service or change air cleaner
Engine stalls when idle
Wrong adjustment of low idle speed - Adjust as required
Fuel injection pump is faulty - Install a new fuel pump or repair
Clogged or defective injector nozzles - Service or replace nozzles if required
Valve clearance is wrong - Check and adjust as required
Engine overheated
Insufficient coolant - Add the coolant. Check for leaks or other malfunctions
Cooling system is dirty or cooling components are damaged - Flush cooling system or change faulty components
Engine oil insufficient - Fill up the oil to required level
Improper fan belt tension or damaged belt - Adjust properly or change the belt
Thermostat malfunction - Check thermostat, replace if necessary
Low engine power
Fuel injectors are clogged or faulty - Test fuel injectors and change if necessary
Fuel injection pressure is wrong - Adjust to correct pressure
Clogged air filter - Replace filter or install new filter element
Clogged oil filter element - Clean or change engine oil filter
Diesel engine is overloaded - Reduce load on the engine
Valve clearance is out of adjustment - Adjustment procedure required
Improperly adjusted low idle speed - Adjust low idling as recommended
Clogged fuel pipes or hoses - Clean fuel hoses and pipes
Engine lost compression: Valves are broken or leaking - Install new valves
Abnormal engine knocking or noise
Incorrect setting of fuel injection pump timing - Check the fuel injection pump timing setting
Fuel injector nozzles are dirty - Inspect injector nozzles and change if required
Engine oil level is insufficient - Checking oil level and add if necessary
Engine not warmed up - Engine is not warmed up to the required temperature
Crankshaft or main bearings are worn out - Change defective components as required
Piston rings are damaged or broken - Piston rings replacement required
Flywheel bolts are loose - Bolts need to be tightened
High oil consumption
Oil leaking: Gaskets or seals are excessively worn - Change to repair leaks
Oil viscosity is incorrect - Fill up with the proper oil viscosity
Damaged or seized piston rings - Replace piston rings
Valve stems and guides are worn - Need to replace the valves
Pistons or cylinder liners are damaged - Inspect liners and pistons, replace as necessary

Electrical System Troubleshooting
Battery cannot be charged
Battery faulty cell - Battery change required
Battery wiring harness failure - Inspect electrical cables for defects, repair or replace
Loose or corroded battery terminals and cables - Tighten or service terminals and cables
Worn belt or improperly adjusted belt tension - Adjust belt tension properly or replace belt
Starter turns slowly
Low battery capacity - Battery is drained, charge it
Battery is not holding charge - Service or change the battery
Battery electrical wire harness damage - Check battery wires for damage, replace or change
Battery cables and terminals are loose or corroded - Tighten or service terminals and cables
Starter motor won't turn
Low battery voltage - Battery needs to be recharged
Discharged or worn battery - Battery needs to be recharged or replaced
Starter motor is defective - Replace or repair starter
Cables harness is improperly connected or disconnected - Inspect cables harness and reconnect it properly

Transmission Troubleshooting
Hard to shift gears
Clutch is not adjusted or faulty - Clutch replacement or adjustment required
Gear shift linkage is loose or broken - Repair or change shift linkage
Shift forks are damaged or worn - Replace defective shift forks
Faulty gear shifting mechanism - Faulty parts must be changed
Low transmission pressure
Oil level is low - Check transmission oil level and add oil as required
Dirty transmission oil filter (if fitted) - Change or clean the transmission oil filter
Faulty relief valve - Replace the valve
Transmission makes excessive noise
Broken or worn bearings - Bearings need to be changed
Insufficient fluid supply - Add transmission fluid as required
Dirty transmission oil - Transmission oil must be changed
Improper backlash or damaged gears - Replace gears or set backlash properly
Bent or worn shift forks - Shift forks need to be changed
Transmission oil leakage
Broken gaskets or seals - Change defective gaskets or seal
Cracked transmission housing - Housing needs to be replaced

Hydraulics Troubleshooting
Hydraulic system overheated
Hydraulic system pressure is not set correctly - Set the hydraulic pressure as required
Main relief valve malfunction or incorrect adjustment - Adjust relief valve or change if required
Contaminated hydraulic oil - Change hydraulic oil
Air in hydraulic system - Inspect the pump seals, suction line, and fittings
Hydraulic oil pressure is low
Hydraulic fluid level is insufficient - Fill the hydraulic system with oil
Hydraulic fluid filter is dirty - Replace filter element or clean if required
Hydraulic pump is faulty - Flow-rate hydraulic pump and replace pump if necessary
Defective or not adjusted hydraulic spool valve - Replace or set properly
Faulty hydraulic cylinder - Inspect the hydraulic cylinder parts for damage or wear and replace if required
Hydraulic piping leaks - Detect leaks in the system and fix it
3-point hitch does not raise or raises very slowly
Lack of hydraulic oil - Check oil level and add hydraulic oil as required
Hydraulic oil is too cold - Allow oil to warm
Hydraulic fluid filter is dirty - Clean or change hydraulic filter
Hydraulic pump not working - Check pump performance and change it if necessary
Main relief valve incorrect adjustment or failure - Adjust or change relief valve
Hydraulic spool valve block is defective or set improper - Adjust correctly or change
Broken hydraulic cylinder - Inspect the hydraulic cylinder parts for damage or wear and replace if required
Loose or damaged suction line - Tighten or replace
Hitch can't drop or drops too slowly
Hydraulic control valve block is defective or set improper - Replace or adjust properly
Hydraulic cylinder is faulty - Inspect cylinder components for wear or damage and change if required
Worn lift arm shaft - Replace the shaft
Hitch has mechanical defects - Change defective or worn hitch components
Hitch lowering or lifting is not smoothly
Air leaks in hydraulic system - Inspect the suction pipe, fittings, and pump seals
Hydraulic oil contamination - Change the oil
Damaged hydraulic oil pump - Check pump flow and install new pump if necessary
Hydraulic control valve block is not set properly or defective - Change or adjust properly
Broken hydraulic cylinder - Check cylinder parts for wear or damage and replace if necessary

Steering System Troubleshooting
Steering is stiff
Steering column is broken or improperly installed - Steering column must be installed properly or replaced
Air leaks in steering system - Bleed the system of air
Incorrect toe-in adjustment - Adjust toe-in properly
Tire pressure is improper - Inflate the tires properly
Steering pump failure - Check the hydraulic steering pump and change if necessary
Damaged or worn hydrostatic steering unit - Check and replace as required
Steering oil level is insufficient - Checking steering oil level and add it if necessary
Steering system has oil leaks - Retighten the connections of the hydraulic steering lines and hoses
Excessive steering wheel free play
Steering column shaft or coupling is worn out - Replace defective part
Hydrostatic steering unit is defective or worn - Inspect and change as required
Steering pump is worn - Check the steering pump and replace if necessary
Faulty or worn steering tie-rod ends or linkage - Change damaged component
Tractor is pulling to left or right
Improper tire pressure - Check the pressure and inflate tires as required
Not adjusted toe-in - Check toe-in and correct
Worn or faulty steering tie-rod ends or linkage - Change damaged part
Hydrostatic steering unit is defective or worn - Replace or repair steering unit as required
Steering cylinder damage - Repair or replace steering cylinder
Front hub bearings are improperly adjusted or defective - Adjust correctly or install new bearings




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