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John Deere 1250 Troubleshooting
The
John Deere 1250 is a 2WD or 4WD compact utility tractor. This model was
manufactured by Yanmar built from 1982 to 1989. The John Deere 1250 driveline
components: a 142.7 cu.in (2.3L) Yanmar 3T95 4-cycle 3-cylinder direct injection
liquid-cooled diesel engine and 9x3 sliding gear transmission.
The engine has a cylinder bore of 3.74" (95 mm), piston stroke of 4.33"
(110 mm), and rated power of 44 hp (32.8 kW). Max. travel speed (forward
and reverse): 15.4 mph (24.8 km/h) / 7.9 mph (12.7 km/h). The open
center hydraulic system includes a gear pump with a rated fluid flow of
11.2 gal/min (42.4 l/min).
The 3-point hitch has a lift capacity of 2240 lbs (1016 kg) at 24" (600
mm) behind pin. The wheel base is 80.7" (2040 mm) for 2-wheel drive
models and 78" (1980 mm) for 4-wheel drive models. The JD 1250 tractor
is compatible with John Deere 100 loader with a maximum lift height of
93.5" (2370 mm) and lift capacity to full height of 1760 lbs (798 kg).
| Engine Troubleshooting |
| Engine will not start or starts up hard |
| Fuel filter is dirty - Install new filter element |
| No fuel supply from the tank - Open the fuel supply valve |
| Air in fuel pipes - Bleed fuel pipes |
| Faulty or dirty injectors - Service or change fuel injectors |
| Fuel injection pump malfunctioning - Replace or repair injection pump |
| Bad cylinder compression - Inspect cylinder block and change defective components |
| Engine stops unexpectedly while running |
| Low coolant temperature - Warm up the engine |
| Fuel lines leaking air - Tighten clamps, change faulty pipes |
| Improper fuel injection - Fuel injection settings required |
| Fuel filter is clogged - Clean the filter or install new filter element |
| Dirty or damaged injectors - Clean or replace fuel injectors |
| Engine starts and immediately stops |
| Incorrectly set fuel injection pump timing - Adjust the fuel injection pump timing correctly |
| Dirty fuel filter element - Install new filter element |
| Clogged or defective injector nozzles - Change injector nozzles |
| Fuel injection pump is defective - Replace or rebuild injection pump |
| Air cleaner element clogging - Change or replace air cleaner element |
| Incorrectly adjusted low idle speed - Correct low idle adjustment |
| Defective fuel injection pump - Change or repair the pump |
| Fuel injector nozzles are dirty or defective - Service or replace nozzles if required |
| Valve clearance is wrong - Check and adjust as required |
| Insufficient coolant - Fill the radiator to the required level. Check for leaks or other malfunctions |
| Cooling system components are worn or system is clogged - Change faulty components or service cooling system |
| Engine oil level low - Fill the crankcase with engine oil |
| Broken fan belt or incorrect belt tension - Adjust properly or replace the belt |
| Defective thermostat - Replace the thermostat |
| Engine power is insufficient |
| Clogged or damaged injectors - Test fuel injectors and change if necessary |
| Incorrect fuel injection pressure - Adjust to proper pressure |
| Air filter clogging - Install new filter element or replace it |
| Clogged oil filter - Change or clean engine oil filter element |
| Diesel engine is overloaded - Reduce the load or use a lower gear |
| The valve clearance is not adjusted - Adjust valve clearance |
| Low idle speed set incorrectly - Need to adjust idle speed |
| Fuel pipes or hoses are dirty - Service fuel hoses and pipes |
| Engine losing compression: Valves are broken or leaking - Replace the valves |
| Abnormal engine knocking or noise |
| Unadjusted fuel injection pump timing - Adjust injection timing |
| Fuel injector nozzles fault - Service or replace nozzles if required |
| Engine oil level low - Need to add engine oil |
| Engine is not fully warmed up - Warm up engine as required |
| Crankshaft or main bearings are worn out - Worn parts replacement required |
| Piston rings are defective or broken - Have piston rings replaced |
| Loose flywheel screws - Check the flywheel screws and tighten as required |
| High engine oil consumption |
| External oil leaks: Damaged seals or gaskets - To repair leaks, replace worn parts |
| Incorrect oil viscosity - Use proper viscosity oil |
| Piston rings are defective or worn - Replace piston rings |
| Damaged valve guides or valve stems - Valves must be replaced |
| Worn cylinder liners or pistons - Check liners and pistons, install new components as required |
| Electrical System Troubleshooting |
| Battery will not charge |
| Battery is defective - Use a new battery |
| Battery wiring harness failure - Inspect electrical cables for defects, repair or replace |
| Loose or corroded terminals and cables - Cables and terminals must be tightened or cleaned |
| Incorrect belt tension adjustment or worn belt - Replace belt or properly adjust belt tension |
| Starter motor cranks slow |
| Low battery output voltage - Battery is drained, recharge it |
| Battery is draining quickly - Service charging system or change battery |
| Damaged battery cable harness - Check electrical cables for damage, repair or replace |
| Battery cables and terminals are loose or corroded - Tighten or service cables and terminals |
| Low battery output voltage - Charge the battery |
| Discharged or faulty battery - Charge or replace the battery |
| Starter motor is damaged - Change or repair starter |
| Improperly connected or disconnected wiring harness - Inspect wiring harness and connect properly |
| Transmission Troubleshooting |
| Hard shifts |
| Worn or misadjusted clutch - Clutch replacement or adjustment required |
| Loose or broken gear shift linkage - Replace or repair the shift linkage |
| Worn or damaged shift forks - Shift forks need to be changed |
| Defective gearshift mechanism - Replace defective components |
| Transmission oil pressure is low |
| Oil level is insufficient - Fill the transmission housing to proper oil level |
| Transmission fluid filter is plugged (if fitted) - Clean or replace the transmission fluid filter |
| Relief valve is faulty - Change relief valve |
| Transmission makes excessive noise |
| Damaged or worn bearings - Bearings need to be replaced |
| Insufficient fluid supply - Fill system with correct transmission fluid level |
| Contaminated transmission fluid - Fill up with fresh transmission fluid |
| Gears are defective or backlash is incorrect - Change worn gears or set backlash correctly |
| Worn or damaged shift forks - Change defective shift forks |
| Worn gaskets or seals - Seals and gaskets replacement required |
| Transmission case is cracked - Replace case or transmission assembly |
| Hydraulics Troubleshooting |
| Hydraulic system is too hot |
| The system pressure has not been corrected - Make the correct settings |
| Main relief valve is damaged or adjusted improperly - Adjust or change relief valve |
| Dirty hydraulic oil - The oil must be changed |
| Aeration in hydraulic system - Check the pump seals, suction pipe, and fittings |
| Hydraulic fluid pressure is insufficient |
| Lack of hydraulic fluid - Check and refill the hydraulic fluid |
| Hydraulic oil filter element is dirty - Replace filter element or clean if required |
| Defective hydraulic pump - Flow-rate pump and change pump if necessary |
| Hydraulic control valve is faulty or out of adjustment - Adjust correctly or replace |
| Hydraulic cylinder malfunction - Inspect cylinder components for wear or damage and change if required |
| Leakage in hydraulic lines - Find leaks in hydraulic 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 |
| Hydraulic fluid is too cold - Allow fluid to warm |
| Hydraulic fluid filter clogging - Service the hydraulic filter or change if required |
| Defective hydraulic pump - Test pump flow rate and replace pump if required |
| Main relief valve is damaged or adjusted improperly - Set up or change the relief valve |
| Damaged or incorrect adjusted hydraulic control valve - Change or set correctly |
| Faulty hydraulic cylinder - Inspect cylinder parts for wear or damage and replace if required |
| Loose or damaged suction line - Tighten or replace |
| Hitch can't drop or drops too slowly |
| Faulty or incorrect setting hydraulic spool valve - Set correctly or replace |
| Hydraulic cylinder malfunction - Check the hydraulic cylinder parts for damage or wear and replace if necessary |
| Damaged hitch cross shaft - Change the shaft |
| Mechanical parts of the hitch are damaged - Change damaged or worn hitch components |
| Three-point hitch raises or lowers not smoothly |
| Hydraulic system sucks air - Inspect the suction pipe, fittings, and pump seals |
| Contaminated hydraulic fluid - Change hydraulic fluid |
| Damaged hydraulic oil pump - Flow-rate pump and change pump if necessary |
| Defective or incorrect setting hydraulic control valve block - Adjust correctly or change |
| Defective hydraulic cylinder - Check cylinder parts for wear or damage and replace if necessary |
| Steering System Troubleshooting |
| Steering is difficult |
| Steering column is broken or improperly installed - Steering column must be installed properly or replaced |
| Aeration in steering system - Bleed the system of air |
| Improper toe-in adjustment - Check toe-in and correct |
| Tires are improperly inflated - Inflate as necessary |
| Steering pump is faulty - Repair or replace steering pump |
| Worn or damaged power steering valve - Repair or change the steering valve |
| Worn steering gear box parts - Change defective steering gear box components |
| Insufficient steering oil - Need to add steering oil |
| Steering system oil leakage - Retighten the connections of the hydraulic steering lines and hoses |
| Excessive free play of steering wheel |
| Steering column shaft or coupling is worn out - Change faulty part |
| Steering valve is defective or worn - Change or repair steering valve if required |
| Damaged steering gear box parts - Defective power steering box components must be replaced |
| Steering pump is worn - Steering pump needs to be repaired or replaced |
| Steering tie-rod ends or linkage are worn - Change damaged component |
| Tractor pulls to left or right |
| Tires are not correctly inflated - Inflate tires as necessary |
| Incorrect toe-in adjustment - Adjust toe-in correctly |
| Steering tie-rod ends or linkage are defective - Replace damaged component |
| Faulty steering gear box components - Defective parts of power steering gearbox must be replaced |
| Faulty or worn power steering valve - Change or repair steering valve if required |
| Front hub bearings are defective or improperly adjusted - Change or adjust bearings correctly |
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| Farm Tractors Technical Specifications |
