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| Home / Farm Tractors / Mahindra Tractors / Mahindra 7520 |
Mahindra 7520 Troubleshooting
The
Mahindra 7520 is a 2-wheel drive or 4-wheel drive utility tractor from 20
Series. This model was manufactured from 2004 to 2008. The components of
Mahindra 7520 powerline system: a 194.1 cubic inches (3.2 L) NE475TC 4-cycle
4-cylinder inline direct injection turbocharged liquid-cooled diesel engine with
a rated power of 75 Hp (56 kW), and synchro shuttle transmission with 12 forward
and 12 reverse gears.
The maximum travel speed (forward/reverse): 21.6 mph (34.5 km/h) and 20.7 mph (33 km/h). The open center hydraulic system includes a gear pump with rated fluid flow of 17 gal/min (64.5 l/min). The Mahindra 7520 is equipped with a hydrostatic power steering system, dry (2WD) or wet (4WD) disc brakes, 11Lx15 (2WD) or 11.2x24 (4WD) front tyres, and 16.9x30 rear tyres. The tractor is compatible with Mahindra ML475 front loader with lift capacity to full height of 3585 lbs (1630 kg), and breakout force of 5655 lbs (2570 kg).
| Diesel Engine Troubleshooting |
| Engine starts hard or won't start |
Air in the fuel lines - Bleed the fuel lines.
Fuel filter plugging - Clean or replace the filter.
Fuel injection nozzles are faulty or clogged - Service or change injection nozzles.
Water in the fuel system - Change fuel and repair fuel system.
The valve clearance is not adjusted - Check and adjust as required.
Fuel injection pump is damaged - Repair or install a new fuel pump.
| Diesel starts but immediately stops |
Dirty air filter - Change air filter element.
Fuel filter element clogging - Replace filter element.
Problems with fuel injection pump tightness - Inspect fuel injection pump for leaks.
Fuel injector fault - Clean or replace fuel injectors.
Damaged fuel injection pump - Replace or rebuild injection pump.
| Engine stops suddenly during operation |
Engine is not warmed up to the required temperature - Engine is not warmed up to the required temperature.
Fuel filter plugged - Change filter element.
Air in fuel tank - Bleed fuel tank.
Fuel injection nozzles fault - If necessary, replace with a new nozzle.
Incorrect adjustment of fuel injection pump timing - Set it up as required.
| Engine stops while idling |
Too low idle RPM - Adjust as required.
Fuel injection pump malfunctioning - Replacement or repair required.
Fuel injector fault - Replace fuel injectors.
The valve clearance is incorrect - Adjust to proper valve clearance.
| Engine power is reduced |
Plugged air cleaner - Service air cleaner.
Fuel injection nozzles are faulty or clogged - Inspect nozzles and replace if necessary.
Improper fuel injection pressure - Correct the pressure settings.
Excessive valve clearance - Have it adjusted.
Low idle speed set incorrectly - Adjust low idle speed.
Clogged fuel hoses or lines - Clean fuel hoses and lines.
Blown cylinder head gasket - Install new cylinder head gasket.
Piston rings are worn or defective - Replace the piston rings as required.
| Engine is overheated |
Low engine coolant - Fill the cooling system and check components for leaks or other faults.
Engine oil level is insufficient - Checking oil level and add if necessary.
Radiator fins are clogged or radiator cap is faulty - Clean radiator or install new cap.
Fan belt is broken or worn - Change as required.
Engine is overloaded - Reduce engine load.
| Oil pressure is insufficient |
Engine oil insufficient - Check and refill the oil.
Engine oil filter is plugged - Change or service engine oil filter.
Improper type of engine oil - Use the specified type of engine oil.
Excessive main bearing oil clearance - Bearing replacement required.
Worn oil pump - Repair or replace.
| Abnormal engine knocking or noise |
Engine oil level is low - Checking oil level and add if necessary.
Low coolant temperature - Engine is not warmed up to the required temperature.
Improper fuel injection timing - Adjust fuel injection pump as required.
Incorrectly set low idle speed - Normalize low idle speed.
Clogged or defective injectors - Clean or replace fuel injectors.
Misaligned or faulty connecting rod - Connecting rod needs to be aligned or changed.
Scored or worn pistons - Replace the pistons.
| Transmission Troubleshooting |
| Insufficient transmission oil pressure |
Lack of transmission oil supply - Check and refill the transmission oil.
Transmission oil filter is dirty (if equipped) - Service or change transmission oil filter.
Stuck relief valve - Replace the valve.
| Transmission makes noise |
Transmission oil insufficient - Fill up the transmission oil.
Transmission oil is dirty - Fill up with fresh transmission oil.
Worn gears or incorrect backlash - Change the gears or set backlash properly.
Bearings are cracked or worn - Change the bearings.
Worn or bent shift forks - Install new shift forks.
Shaft splines are damaged or worn - Install a new shaft.
| Gears are hard to shift |
Gear shift linkage is worn or rusty - Install new shift linkage.
Shift forks are worn or bent - Install new shift forks.
Worn out parts of the gearshift mechanism - Replace worn parts.
Clutch is faulty or misadjusted - Replace or adjust clutch.
| Transmission fluid leakage |
Transmission oil level is exceeded - Correct the oil volume.
Seals or gaskets are worn - Replace worn gaskets or seal.
| Hydraulic System Troubleshooting |
| Hydraulic oil pressure is insufficient |
Insufficient hydraulic oil - Checking hydraulic oil level and add if necessary.
Clogged hydraulic fluid filter - Clean the hydraulic filter element or replace if necessary.
Faulty hydraulic pump - Repair or replace hydraulic oil pump.
Incorrect setting hydraulic spool valve - Use the correct setting.
Hydraulic cylinder malfunction - Install a new hydraulic cylinder or repair it.
Leaking hydraulic pipes - Inspect the system for leaks and fix it.
| Hydraulic system is too hot |
Defective main relief valve - Install a new relief valve.
Improper hydraulic fluid type - Use the proper type of hydraulic fluid.
Contaminated hydraulic fluid - Change hydraulic fluid.
There is air in the hydraulic system - Bleed hydraulic system.
| Hitch can't lift or lifts too slowly |
Excessive load on hitch - Load needs to be reduced.
Insufficient hydraulic fluid - Fill the system to proper hydraulic fluid level.
Hydraulic oil filter element is clogged - Service the hydraulic filter or change if required.
Hydraulic pump failure - Replace or repair hydraulic oil pump.
Main relief valve malfunction - Install a new relief valve.
Defective hydraulic control valve - Repair or change the valve.
Faulty hydraulic cylinder - Change or repair hydraulic cylinder.
Loose or broken suction line - Tighten the pipe or replace it.
| Hitch not lowering or hitch lowers slowly |
Incorrect adjusted hydraulic control valve - Adjust correctly.
Hydraulic cylinder is broken - Repair or install a new hydraulic cylinder.
The hitch has not been adjusted - The 3-point hitch must be adjusted.
Hitch rock shaft is worn Replace the shaft.
| Jerky lifting or lowering of three-point hitch |
Air in the hydraulic system - Air bleeding.
Dirty hydraulic fluid - The fluid must be changed.
Faulty hydraulic pump - Install a new hydraulic oil pump.
Hydraulic control valve block is faulty - Repair or replace the valve.
Broken hydraulic cylinder - Replace or repair hydraulic cylinder.
| Steering Troubleshooting |
| Difficult steering |
Defective or incorrectly mounted steering column - Change steering column or mount correctly.
Air trapped inside steering system - Bleed the steering system.
Incorrect toe-in - Check and adjust toe-in.
Uneven wear on front tires - Replace the tires.
Steering pump is worn - Install a new steering pump.
Faulty or stuck pump flow control valve - Flush or change flow control valve.
Insufficient steering fluid - Fill up the steering fluid.
| Excessive free play of steering wheel |
Steering column coupling or shaft is worn - Replace defective part.
Worn steering pump - Install a new steering pump.
Worn or loose steering linkage joints - Change or repair steering linkage.
| Tractor pulls to left or right |
Front tyres wear unevenly - Change the tyres.
Incorrect toe-in - Check and adjust toe-in.
Loose or worn steering linkage components - Inspect and replace as required.
Incorrectly adjusted or worn front wheel bearings - Change or adjust bearings correctly.
| Electrical Troubleshooting |
| Battery will not charge |
Loose or corroded electrical wiring connections - Clean or tighten wiring connections.
Battery terminal clamps are defective - Replace terminal clamps.
Battery failing - Change the battery.
Loose or defective belt - Need to adjust belt tension or replace belt.
| Starter turns slowly |
Low battery voltage - Battery is drained, charge it.
Battery is draining quickly - Service charging system or install new battery.
Bad battery terminals or disconnected wiring - Check wiring connections and replace or clean terminals.
| Starter motor is not working |
Battery is low or faulty - Recharge or replace battery.
Disconnected or incorrectly connected wires - Inspect battery wires and connect correctly.
Low battery output voltage - Battery is drained, recharge it.
Defective starter motor - Starter should be changed.
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| Farm Tractors Technical Specifications |