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John Deere 4755 Troubleshooting
The
John Deere 4755 is a 2WD or 4WD row-crop tractor from 4055 series. This model
was manufactured between 1989 and 1991. The JD 4755 tractor is powered by John
Deere 6466 six-cylinder direct injection turbocharged intercooled diesel engine
with operating power of 190 Hp (141.5 kW) and 820 Nm (607 lb-ft) of peak torque
at 1210 rpm.
The JD 4755 is fitted with two types of transmission. Type 1: 16x6 Quad
Range partial powershift transmission. Type 2: Power Shift transmission
with 15 forward and 4 reverse gears.
Max. forward speed - 19.6 mph (31.5 kph), max. reverse speed - 12.6 mph
(20.3 kph). The closed center hydraulic system used a piston pump with a
flow of 29.5 gal/min (111.5 l/min). The hydraulic pressure is 174.5 bar
(2530 psi). The John Deere 4755 is equipped with 11.00x16 front tyres
and 20.8x38 rear tyres. The wheel base is 118.5" (3000 mm) for 2-wheel
drive models and 117.1" (2970 mm) for 4-wheel drive models.
Compatible attachments for the tractor: John Deere 280 loader with a
lift capacity to max height of 4580 lbs (2077 kg), and John Deere 840
loader with a lift capacity to max height of 4972 lbs (2260 kg).
| Engine Troubleshooting |
| Engine is not starting or hard starting |
| Dirty fuel filter element - Change filter element |
| No fuel injection - Open fuel cock to inject fuel |
| Fuel-line is leaking air - Retighten clamps, replace defective pipes |
| Faulty or dirty injectors - Change fuel injectors |
| Faulty fuel injection pump - Repair or replace injection pump |
| Low compression - Check cylinder block and replace damaged components |
| Engine shuts off unexpectedly while running |
| Engine is not fully warmed up - Warm up to required temperature |
| Air in fuel lines - Bleed fuel lines |
| Irregular fuel injection - Adjust fuel injection timing |
| Fuel filter plugging - Change filter element |
| Dirty or damaged injectors - Test fuel injectors and change if necessary |
| Engine starts but immediately shuts off |
| Unadjusted fuel injection pump timing - Fuel pump timing settings need to be corrected |
| Fuel filter clogging - Install new filter element |
| Fuel injector nozzles are defective or dirty - Change injector nozzles |
| Fuel injection pump is not working correctly - Change pump or rebuild it |
| Dirty air cleaner element - Change or replace air cleaner element |
| Incorrectly adjusted low idle speed - Correct low idle adjustment |
| Fuel injection pump is not operating properly - Replace or repair injection pump |
| Fuel injector nozzles are clogged or faulty - Test injector nozzles and replace as required |
| Valve clearance is not correct - Adjust to proper valve clearance |
| Low coolant level - Top up coolant. Check and repair damage to the cooling system if required |
| Cooling system parts are defective or system is dirty - Flush cooling system or replace faulty parts |
| Not enough engine oil - Fill up the oil to required level |
| Fan belt tension is not adjusted or belt is worn - Adjust properly or replace the belt |
| Thermostat is defective - Check thermostat, replace if necessary |
| Diesel engine is losing power |
| Clogged or damaged injectors - Change fuel injectors |
| Incorrect fuel injection pressure - Repair or replace injection pump |
| Dirty air filter - Replace or clean the air filter element |
| Oil filter element clogged - Service or change engine oil filter element |
| Engine is running overloaded - Reduce the load or use a lower gear |
| Improper valve clearance - Correct valve clearance |
| Wrong adjustment of low idle speed - Correct low idle adjustment |
| Dirty fuel hoses or pipes - Clean fuel pipes and hoses |
| Poor engine compression: Inlet or outlet valves are defective - Install new valves |
| Unadjusted fuel injection pump timing - Adjust the fuel injection pump timing correctly |
| Fuel injector nozzles are defective or dirty - Service or replace injector nozzles |
| Engine oil level low - Check and refill engine oil |
| Engine not warmed up - Engine is not warmed up to the required temperature |
| Main bearings or crankshaft failure - Worn parts replacement required |
| Stuck or worn piston rings - Have piston rings replaced |
| The flywheel to crankshaft bolts are loose - Tighten bolts as required |
| Engine oil consumption is too high |
| External oil leaks: Seals or gaskets are wearing excessively - Replace to repair leaks |
| Incorrect oil viscosity - Use oil of correct viscosity |
| Piston rings are stuck or worn - Install new piston rings |
| Damaged valve stems or valve guides - Valves need to be changed |
| Scuffed cylinder liners or pistons - Check liners and pistons, replace as required |
| Electrical System Troubleshooting |
| Battery does not charge |
| Defective battery - Use a new battery |
| Bad battery cable harness - Inspect cables for malfunctions, repair or change |
| Corroded or loose cables and terminals - Tighten or clean cables and terminals |
| Incorrect belt tension adjustment or worn belt - Adjust belt tension as required or change belt |
| Low battery output voltage - Battery is drained, charge it |
| Battery is draining quickly - Service battery or replace it |
| Bad battery wiring harness - Inspect wiring for malfunctions, replace or repair |
| Loose or corroded terminals and cables - Tighten or clean cables and terminals |
| Battery capacity is low - Charge the battery |
| Discharged or faulty battery - Replace or charge as required |
| Defective starter motor - Repair or replace starter |
| Incorrectly connected or disconnected wires - Check battery wires and connect correctly |
| Transmission Troubleshooting |
| Difficult to shift gears |
| Worn or incorrectly adjusted clutch - Adjust or change the clutch |
| Stuck or damaged gear shift linkage - Change defective shift linkage |
| Bent or worn shift forks - Change the shift forks |
| Worn gear shift mechanism - Replace worn components |
| Insufficient transmission fluid pressure |
| Not enough fluid in transmission - Check transmission fluid level and add it as required |
| Clogged transmission fluid filter element (if fitted) - Replace or clean transmission fluid filter |
| Relief valve failure - Replace the valve |
| Cracked or worn bearings - Faulty bearings should be replaced |
| Not enough oil in transmission - Add transmission oil as required |
| Transmission fluid contamination - Change transmission fluid |
| Gears are worn or backlash is improper - Set backlash correctly or change the gears |
| Shift forks are damaged or worn - Install new shift forks |
| Transmission fluid leaking |
| Gaskets or seals are damaged - Replace worn seal or gaskets |
| Transmission housing is cracked - Replace housing or transmission assembly |
| Hydraulics Troubleshooting |
| Hydraulic system is overheated |
| System pressure has not been adjusted correctly - Pressure needs to be adjust correctly |
| Unadjusted or defective main relief valve - Replace or set up the relief valve |
| Hydraulic fluid is contaminated - Fill up with new hydraulic fluid |
| Hydraulic system sucks air - Check the suction line, pump seals, and fittings |
| Hydraulic oil pressure is low |
| Hydraulic oil level is low - Fill the hydraulic system with oil |
| Hydraulic oil filter element is dirty - Clean the hydraulic filter or install new filter element |
| Hydraulic pump malfunction - Test pump flow rate and replace pump if required |
| Hydraulic spool valve is faulty or out of adjustment - Adjust properly or replace |
| Hydraulic cylinder is broken - Check cylinder components for damage or wear and change if necessary |
| Hydraulic piping leaks - Find leaks in hydraulic system and repair it |
| 3-point hitch won't raise or raises slowly |
| Not enough hydraulic oil in the system - Fill the hydraulic system with oil |
| Cold hydraulic oil - Warm up the oil |
| Hydraulic oil filter clogging - Replace filter element or clean if required |
| Hydraulic pump not working - Check pump performance and change it if necessary |
| Unadjusted or defective main relief valve - Adjust or change relief valve |
| Defective or not adjusted hydraulic control valve - Set correctly or replace |
| Broken hydraulic cylinder - Check the hydraulic cylinder parts for damage or wear and replace if necessary |
| Damaged or loose hydraulic suction line - Tighten or change it |
| Hitch won't lower or lowers slowly |
| Hydraulic control valve block is faulty or out of adjustment - Set correctly or replace |
| Hydraulic cylinder malfunction - Check the hydraulic cylinder parts for damage or wear and replace if necessary |
| Hitch cross shaft is damaged - Change the shaft |
| Defective mechanical parts of the hitch - Replace faulty or worn hitch components |
| Hitch raises or lowers not smoothly |
| Air leaks in hydraulic system - Inspect the pump seals, suction pipe, and fittings |
| Hydraulic fluid is contaminated - Fill up with new hydraulic fluid |
| Hydraulic pump not working - Check the pump capacity and replace pump if required |
| Hydraulic control valve is defective or set improper - Set correctly or replace |
| Faulty hydraulic cylinder - Check cylinder parts for wear or damage and replace if necessary |
| Steering System Troubleshooting |
| Excessive effort to steer |
| Steering column is defective or incorrectly installed - Steering column must be installed correctly or replaced |
| Air leaks in steering system - Air-bleed steering system |
| Improper toe-in adjustment - Adjust toe-in wheels properly |
| Front tires are worn out - Install new tires |
| Faulty steering pump - Replace or repair steering pump |
| Damaged or worn steering valve assembly - Change or repair steering valve if required |
| Relief valve seizing or malfunction - Replace or install new relief valve |
| Not enough steering oil - Check oil level and add steering oil as required |
| Steering system has oil leaks - Tighten joints of hydraulic pipes and hoses in steering system |
| Excessive steering wheel play |
| Steering column coupling or shaft is worn - Replace defective part |
| Steering valve assembly has wear or damage - Repair or change the steering valve |
| Hydraulic steering pump is defective - Install a new steering pump |
| Faulty or worn steering linkage or tie-rod ends - Replace damaged component |
| Front wheels wander to left or right |
| Tires are not correctly inflated - Inflate tires as necessary |
| Not adjusted toe-in - Adjust toe-in wheels properly |
| Worn or faulty steering tie-rod ends or linkage - Change failed component |
| Steering valve assembly has wear or damage - Change or repair steering valve if required |
| Front hub bearings are worn or incorrectly adjusted - Adjust properly or change bearings |
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| Farm Tractors Technical Specifications |
