The John Deere 1120 is a versatile utility tractor renowned for its reliability and adaptability across various agricultural tasks. Produced between 1968 and 1975, it filled a crucial niche in the John Deere lineup, offering a balance of power and maneuverability suitable for small to medium-sized farms. This tractor proved itself capable in plowing, tilling, planting, and even light loader work, making it a popular choice for farmers seeking a robust and efficient machine. Its simple yet effective design has ensured that many units remain in service today, a testament to John Deere's commitment to quality and longevity.
The 1120 typically featured a three-cylinder diesel engine, delivering adequate horsepower for its intended applications. Engine specifics varied slightly depending on the year of manufacture, but generally produced around 40 to 45 horsepower. The tractor was offered with different transmission options, including a synchro range transmission, providing the operator with a wide range of gear selections for optimal performance in varying field conditions. Its relatively compact dimensions and power steering (optional on some models, standard on others) enhanced its maneuverability, making it easy to operate in tight spaces.
Before performing any maintenance or repair work on your John Deere 1120, it is imperative to prioritize safety. Tractors are powerful machines, and improper procedures can lead to serious injury or even death. Always disconnect the battery's negative cable before commencing any electrical work to prevent accidental shorts or electrocution. Engage the parking brake and block the wheels to prevent the tractor from rolling during maintenance.
When working with hydraulic systems, remember that hydraulic fluid is under high pressure. Release all pressure before disconnecting any lines or fittings. Wear safety glasses to protect your eyes from flying debris or sprayed fluid. Never attempt to check for leaks with your bare hands; instead, use a piece of cardboard or wood. Familiarize yourself with the tractor's safety features, such as the rollover protection structure (ROPS) and seat belt, and ensure they are in good working condition before operating the tractor.
To effectively service your John Deere 1120, you will need a comprehensive set of tools and equipment. A well-stocked toolbox should include a variety of wrenches, sockets (both metric and standard), screwdrivers (Phillips and flathead), pliers, and a hammer. Specialized tools, such as a torque wrench, multimeter, and compression tester, will also be necessary for more complex repairs.
In addition to hand tools, consider investing in a few pieces of equipment that can greatly simplify maintenance tasks. A floor jack and jack stands are essential for safely lifting and supporting the tractor. An engine hoist or cherry picker can be invaluable for removing and installing heavy components. A parts washer will help you clean greasy or dirty parts, and a service manual specifically for the John Deere 1120 is an absolute must for referencing specifications, procedures, and troubleshooting information. With the right tools and knowledge, you can confidently tackle most maintenance and repair tasks on your tractor.
Before embarking on any engine repair, a thorough disassembly and inspection are paramount to accurately diagnose the root cause of the issue and determine the necessary repair procedures. Begin by carefully removing all external components such as the air cleaner, fuel lines, electrical connections, and any associated brackets or accessories. Document the location of each component and fastener as you disassemble, utilizing photographs or diagrams to ensure proper reassembly. Pay close attention to the condition of each part as it is removed, noting any signs of wear, damage, or corrosion. This initial assessment will provide valuable insights into the overall health of the engine and guide the subsequent inspection process.
Once the external components have been removed, proceed with the disassembly of the major engine components, following the manufacturer's recommended sequence. Typically, this involves removing the intake and exhaust manifolds, valve cover, rocker arms, cylinder head, oil pan, and timing cover. As each component is removed, carefully inspect it for any signs of damage or wear, such as cracks, warpage, excessive carbon buildup, or worn bearings. Use precision measuring instruments, such as micrometers and dial indicators, to measure critical dimensions and compare them to the manufacturer's specifications. Record all measurements and observations, as this information will be crucial in determining which parts need to be replaced or reconditioned. Thoroughly clean all disassembled parts with a suitable solvent to remove any dirt, grease, or oil, allowing for a more accurate inspection.
The cylinder head is a crucial component of the engine, responsible for housing the valves, guiding the flow of intake air and exhaust gases, and providing a combustion chamber. Over time, the cylinder head can develop various issues, such as cracks, warpage, worn valve guides, or damaged valve seats. To ensure optimal engine performance, it is essential to thoroughly inspect and service the cylinder head during any engine repair. Begin by cleaning the cylinder head thoroughly with a parts washer and a suitable cleaning solvent. This will remove any carbon deposits, oil, or other contaminants that may be present.
Carefully inspect the cylinder head for cracks, particularly in the valve seat area and around the spark plug holes. Use a straightedge and feeler gauges to check for warpage on the cylinder head mating surface. If the warpage exceeds the manufacturer's specifications, the cylinder head may need to be resurfaced. Inspect the valve guides for wear by measuring the valve stem-to-guide clearance using a dial indicator. If the clearance is excessive, the valve guides may need to be replaced. Finally, inspect the valve seats for damage, such as pitting or erosion. If the valve seats are damaged, they may need to be reconditioned by grinding or replacing them.
The engine block is the foundation of the engine, providing structural support for all other components and housing the cylinders, crankshaft, and camshaft. Over time, the engine block can develop various issues, such as cracks, warpage, or worn cylinder bores. To ensure optimal engine performance, it is essential to thoroughly inspect and service the engine block during any engine repair. Begin by cleaning the engine block thoroughly with a parts washer and a suitable cleaning solvent. This will remove any dirt, grease, or oil that may be present.
Carefully inspect the engine block for cracks, particularly around the main bearing journals and cylinder bores. Use a straightedge and feeler gauges to check for warpage on the cylinder head mating surface. If the warpage exceeds the manufacturer's specifications, the engine block may need to be resurfaced. Inspect the cylinder bores for wear, scoring, or taper. Use a bore gauge to measure the cylinder bore diameter at several points along its length. If the wear exceeds the manufacturer's specifications, the cylinder bores may need to be honed or bored to the next oversize. Finally, inspect the main bearing journals for wear or damage. If the journals are worn or damaged, the engine block may need to be align-bored.
The pistons and connecting rods are responsible for converting the combustion pressure into reciprocating motion, which is then transferred to the crankshaft. These components are subjected to high stresses and temperatures, and over time, they can develop various issues, such as worn piston rings, worn piston skirts, or bent connecting rods. To ensure optimal engine performance, it is essential to thoroughly inspect and service the pistons and connecting rods during any engine repair. Begin by cleaning the pistons and connecting rods thoroughly with a parts washer and a suitable cleaning solvent. This will remove any carbon deposits, oil, or other contaminants that may be present.
Carefully inspect the pistons for cracks, particularly around the piston pin bore and ring grooves. Measure the piston diameter at several points to check for wear. If the wear exceeds the manufacturer's specifications, the pistons may need to be replaced. Inspect the piston rings for wear or damage. Measure the ring end gap using a feeler gauge. If the end gap exceeds the manufacturer's specifications, the piston rings need to be replaced. Inspect the connecting rods for bends or twists. Use a connecting rod aligning tool to check for proper alignment. If the connecting rod is bent or twisted, it needs to be replaced. Finally, inspect the connecting rod bearings for wear or damage. If the bearings are worn or damaged, they need to be replaced.
The crankshaft is a critical component of the engine, responsible for converting the reciprocating motion of the pistons into rotational motion, which is then used to drive the vehicle. The crankshaft is subjected to high stresses and temperatures, and over time, it can develop various issues, such as worn main bearing journals, worn connecting rod journals, or cracks. To ensure optimal engine performance, it is essential to thoroughly inspect and service the crankshaft during any engine repair. Begin by cleaning the crankshaft thoroughly with a parts washer and a suitable cleaning solvent. This will remove any dirt, grease, or oil that may be present.
Carefully inspect the crankshaft for cracks, particularly around the main bearing journals and connecting rod journals. Measure the diameter of the main bearing journals and connecting rod journals at several points to check for wear. If the wear exceeds the manufacturer's specifications, the crankshaft may need to be reground to the next undersize. Inspect the crankshaft for straightness. Use a dial indicator to check for runout. If the runout exceeds the manufacturer's specifications, the crankshaft may need to be straightened. Finally, inspect the crankshaft for any signs of damage to the oil passages. Ensure that the oil passages are clear and free of any obstructions.
After thoroughly inspecting and reconditioning or replacing all necessary components, the engine can be reassembled. Follow the manufacturer's recommended assembly sequence and torque specifications to ensure proper engine function and longevity. It is crucial to use new gaskets and seals throughout the assembly process to prevent leaks and maintain proper sealing. Apply engine assembly lubricant to all moving parts, such as bearings, pistons, and camshaft lobes, to reduce friction during initial startup.
Once the engine has been fully assembled, it can be installed back into the tractor. Reconnect all fuel lines, electrical connections, and other accessories, ensuring that they are properly secured and tightened. Fill the engine with the correct type and quantity of engine oil and coolant. Before starting the engine, prime the oil pump by cranking the engine over without starting it. This will ensure that the engine is properly lubricated upon initial startup. Once the engine is started, monitor it closely for any leaks, unusual noises, or other issues. Adjust the engine timing and idle speed as necessary. Allow the engine to run for a period of time to break in the new components and ensure proper operation.
The fuel system on the John Deere 1120 is a vital component for ensuring reliable engine operation. A clean and properly functioning fuel system delivers the necessary fuel to the injectors at the correct pressure and timing, allowing for efficient combustion and optimal power output. Regular maintenance and timely repairs are critical to prevent fuel starvation, poor engine performance, and potential engine damage. This chapter provides a comprehensive guide to servicing the fuel system, covering everything from the fuel tank to the injectors.
The fuel tank stores the diesel fuel that powers the engine. Over time, sediment, rust, and other contaminants can accumulate in the tank, potentially clogging fuel lines and damaging the fuel pump and injectors. It is important to inspect the fuel tank regularly for signs of corrosion or leaks, and to clean the tank periodically to remove any accumulated debris. Inspect the fuel cap to ensure it is sealing properly, as a damaged or missing cap can allow water and other contaminants to enter the tank.
Fuel lines connect the fuel tank to the fuel filter, injection pump, and injectors. These lines are typically made of rubber or metal, and they can become brittle, cracked, or clogged over time. Regularly inspect the fuel lines for signs of damage, such as cracks, leaks, or swelling. Replace any damaged lines immediately to prevent fuel leaks and ensure proper fuel delivery. Ensure the fuel lines are properly secured and routed to prevent chafing or kinking. Use proper fuel line clamps and fittings for secure connections.
The fuel filter is designed to remove contaminants from the fuel before it reaches the injection pump and injectors. A clogged fuel filter can restrict fuel flow, leading to poor engine performance, reduced power, and even engine stalling. Regular fuel filter replacement is essential for maintaining a clean fuel system. It is recommended to replace the fuel filter at the intervals specified in the John Deere 1120 operator's manual, or more frequently if the tractor is operated in dusty or dirty conditions.
When replacing the fuel filter, always use a genuine John Deere filter or a high-quality aftermarket filter that meets or exceeds John Deere specifications. Ensure the new filter is properly installed and tightened to prevent leaks. Before starting the engine after replacing the fuel filter, it is important to bleed the fuel system to remove any air that may have entered the lines. Follow the specific bleeding procedure outlined in the operator's manual. Improper bleeding can lead to hard starting, rough running, or engine damage.
The injection pump is responsible for delivering the correct amount of fuel to the injectors at the precise timing. This is a complex piece of equipment that is essential for the performance of the engine. The injection pump can be affected by wear and tear. This can reduce the machine’s productivity. This component can be the hardest to service and should only be serviced by a professional.
The injection pump may need to be checked for calibration to make sure it is within the manufacturer's specifications. If there are any issues that occur with the injection pump, take it to an authorized John Deere dealer or a qualified diesel mechanic for repairs. An injection pump that isn’t working correctly can cause the machine to not run correctly or potentially damage other expensive parts.
The injectors spray fuel into the combustion chambers, where it mixes with air and ignites. Over time, injectors can become clogged with carbon deposits, leading to poor fuel atomization, reduced power, and increased emissions. Regular injector cleaning or replacement is necessary to maintain optimal engine performance. To inspect the injectors, remove the injectors from the engine and visually inspect them for signs of damage or excessive carbon buildup.
If the injectors are clogged, they can be cleaned using a specialized injector cleaning machine or a suitable solvent. However, injector cleaning is a delicate process, and it is important to follow the manufacturer's instructions carefully to avoid damaging the injectors. If the injectors are severely damaged or clogged beyond repair, they should be replaced with new or remanufactured injectors. When reinstalling the injectors, ensure they are properly seated and torqued to the correct specification. Always use new sealing washers to prevent fuel leaks.
The battery is the heart of the electrical system, providing the initial power to start the engine and run various electrical components when the engine is not running or at low speeds. Maintaining a healthy battery is crucial for reliable operation of your John Deere 1120. Regularly inspect the battery terminals for corrosion, which can impede current flow and lead to starting problems. Clean any corrosion with a wire brush and a solution of baking soda and water, ensuring to disconnect the battery cables before cleaning to prevent accidental short circuits. Always reconnect the positive terminal first when reattaching the cables.
Periodically check the battery's electrolyte level, if applicable (some batteries are sealed). If the levels are low, add distilled water until they reach the appropriate mark. Avoid overfilling, as this can cause acid to spill out during charging. A hydrometer can be used to check the specific gravity of the electrolyte, which provides an indication of the battery's state of charge. A fully charged battery should have a specific gravity reading between 1.265 and 1.285. If the battery consistently fails to hold a charge or exhibits other signs of weakness, it may be time for a replacement. Always dispose of old batteries properly, as they contain hazardous materials.
When jump-starting the tractor, always follow the correct procedure to avoid damaging the electrical system. Connect the positive (+) jumper cable to the positive (+) terminal of the discharged battery first, then connect the other end of the positive cable to the positive (+) terminal of the booster battery. Next, connect one end of the negative (-) jumper cable to the negative (-) terminal of the booster battery. Finally, connect the other end of the negative (-) cable to a good ground on the tractor being jump-started, such as the engine block, away from the battery and fuel lines. After starting, disconnect the cables in the reverse order. Using this method ensures safety and prevents electrical surges that could damage sensitive components.
The starter motor is responsible for cranking the engine, initiating the combustion cycle. A faulty starter motor can prevent the tractor from starting, leading to downtime and frustration. Common problems include a worn-out solenoid, damaged armature, or sticking bendix drive. If the starter motor clicks but doesn't turn the engine, the solenoid may be the culprit. The solenoid is an electromagnet that engages the starter motor and connects it to the battery.
To diagnose starter motor issues, first, visually inspect the starter for any signs of damage, such as cracked housings or loose connections. Use a multimeter to check for voltage at the starter motor terminals when the ignition switch is in the start position. If voltage is present but the starter doesn't operate, the starter motor itself is likely faulty and requires repair or replacement. Removing the starter motor involves disconnecting the battery, detaching the electrical connections to the starter, and unbolting the starter from the engine.
When installing a new or rebuilt starter motor, ensure that the mounting surfaces are clean and free of debris. Tighten the mounting bolts to the specified torque to prevent vibration and potential damage. Reconnect the electrical connections securely and double-check the wiring for proper polarity. After installation, test the starter motor to ensure it operates smoothly and engages the engine correctly. If the starter motor still malfunctions after replacement, further investigation of the wiring harness and ignition switch may be necessary.
The alternator is responsible for charging the battery and providing power to the electrical system while the engine is running. A malfunctioning alternator can result in a dead battery and a non-operational tractor. Key things to consider when diagnosing an alternator include the battery light constantly on, the battery draining quickly, or the tractor running with low electrical power.
To diagnose alternator problems, start by visually inspecting the alternator belt for proper tension and condition. A loose or worn belt can slip, reducing the alternator's output. Use a multimeter to check the alternator's output voltage while the engine is running. A healthy alternator should produce approximately 13.5 to 14.5 volts. If the voltage is significantly lower or higher, the alternator may be faulty. Also, be sure to inspect the wiring harness and ground connections for any breaks or shorts, which may cause low output.
If the alternator is suspected of being faulty, it can be removed for testing or replacement. Disconnect the battery before disconnecting any wiring on the alternator. You may need to loosen the alternator belt tension by releasing an adjustment. Always note the correct orientation and position of all wires and hardware you remove. When installing a new or rebuilt alternator, ensure proper belt tension and alignment. Double-check all electrical connections to avoid polarity issues.
Understanding the wiring diagrams for your John Deere 1120 is essential for effective electrical troubleshooting. Wiring diagrams provide a visual representation of the electrical circuits, showing the connections between various components. These diagrams are crucial for tracing circuits, identifying faulty wiring, and making repairs. Familiarize yourself with the symbols and abbreviations used in the diagrams to interpret them accurately.
When troubleshooting electrical problems, start by identifying the affected circuit and consulting the wiring diagram. Use a multimeter to check for voltage, continuity, and resistance in the circuit. Look for any signs of damaged wiring, such as frayed insulation, corroded connectors, or loose terminals. Use a test light to verify that power is reaching the correct points in the circuit. Always disconnect the battery before working on the electrical system to prevent accidental short circuits.
Common electrical problems include blown fuses, short circuits, and open circuits. Fuses protect the electrical system from overloads and short circuits. If a fuse blows repeatedly, there may be a short circuit in the wiring. A short circuit occurs when a wire makes direct contact with ground, bypassing the intended load. An open circuit occurs when there is a break in the wiring, preventing current from flowing. By systematically tracing the circuit and testing the wiring, you can identify and repair these problems. Correct wiring and connections can ensure your tractor runs smoothly.
Before embarking on any significant transmission repairs for your John Deere 1120, a thorough disassembly and inspection are crucial steps. This meticulous process allows you to accurately diagnose the root cause of the problem and identify all worn or damaged components that require replacement or reconditioning. Begin by carefully draining the transmission oil and thoroughly cleaning the exterior of the transmission housing. This will provide a clean working environment and prevent contaminants from entering the transmission during disassembly. Pay close attention to any signs of external damage, such as cracks or leaks, which can offer valuable clues to the transmission's internal condition. Document the location and condition of all parts as you remove them, using a camera or notepad to record the disassembly process for easy reassembly.
Once the transmission is clean and ready for disassembly, carefully remove the external components, such as the PTO shaft, shift levers, and any external hydraulic lines. As you remove each component, inspect it for wear, damage, or corrosion. Pay particular attention to the condition of the seals and O-rings, as these are common sources of leaks. Use appropriate tools to avoid damaging the components during removal. With the external components removed, proceed with disassembling the transmission housing, carefully separating the various sections. As you separate the housings, be mindful of the placement of gears, shafts, and bearings, and carefully remove them, labeling each part and its original location. Thoroughly inspect each gear, shaft, and bearing for signs of wear, pitting, cracks, or other damage. Use precision measuring tools, such as micrometers and dial indicators, to check the dimensions of the gears and shafts against the manufacturer's specifications. Any parts that are worn or damaged beyond acceptable limits should be replaced.
The gears and shafts within your John Deere 1120 transmission are critical components that transfer power and determine the tractor's speed and torque. Maintaining these parts to factory standards is absolutely essential. Over time, these parts can experience wear and tear, leading to reduced performance or complete failure. When servicing gears, carefully inspect the teeth for signs of pitting, chipping, or excessive wear. Minor imperfections can often be addressed through polishing or light grinding, but severely damaged gears should always be replaced. Check the gear splines for wear or damage, ensuring they are properly engaged with the mating shaft. Shafts should be inspected for straightness, wear, and damage to the splines or bearing surfaces. Any bent or excessively worn shafts should be replaced to ensure proper alignment and prevent further damage to the transmission.
When replacing gears or shafts, always use genuine John Deere parts or high-quality aftermarket replacements that meet or exceed the original manufacturer's specifications. Aftermarket parts should always be inspected. Before installing new gears or shafts, ensure that all mating surfaces are clean and lubricated with the recommended transmission oil. Proper lubrication is crucial to minimize friction and prevent premature wear. When installing gears onto shafts, use appropriate tools and techniques to avoid damaging the gears or shafts. Always follow the manufacturer's torque specifications when tightening fasteners to ensure proper clamping force and prevent loosening or breakage. After installation, carefully check the gear mesh to ensure proper engagement and minimal backlash. If necessary, adjust shimming or other adjustments to achieve the correct gear mesh.
Bearings and seals play a crucial role in the smooth and efficient operation of your John Deere 1120 transmission. Bearings support the rotating shafts and gears, while seals prevent oil leaks and keep contaminants out. Over time, bearings can wear out or become damaged, leading to noise, vibration, and reduced performance. Seals can also deteriorate, causing oil leaks and potentially damaging other transmission components. During the transmission disassembly and inspection process, carefully examine all bearings and seals for signs of wear, damage, or leaks. Replace any bearings that are noisy, rough, or have excessive play. Replace any seals that are cracked, hardened, or leaking.
When replacing bearings, always use the correct type and size bearing for your John Deere 1120 transmission. Genuine John Deere bearings or high-quality aftermarket replacements that meet or exceed the original manufacturer's specifications are recommended. Before installing new bearings, ensure that the bearing surfaces are clean and free of any debris. Use a bearing press or appropriate tools to install the bearings into the housing, taking care not to damage the bearings or the housing. When installing seals, lubricate the seal lips with the recommended transmission oil to prevent damage during installation. Use a seal driver or appropriate tools to install the seals into the housing, ensuring that they are properly seated and oriented. After installation, carefully inspect the bearing and seal areas for any signs of leakage or misalignment.
After all necessary repairs and replacements have been completed, the final step is to reassemble and reinstall the transmission in your John Deere 1120. This is a critical step that requires careful attention to detail and adherence to the manufacturer's specifications. Before beginning the reassembly process, ensure that all parts are clean, lubricated, and properly aligned. Use the diagrams and notes you took during disassembly as a guide to ensure that all parts are installed in the correct order and orientation. Begin by installing the internal components, such as the gears, shafts, and bearings, into the transmission housing. Ensure that all parts are properly seated and that the gear mesh is correct. Use the appropriate tools and techniques to avoid damaging any of the components.
Once the internal components are installed, carefully assemble the transmission housing sections, ensuring that all surfaces are clean and free of any debris. Use new gaskets or seals to prevent leaks. Tighten the housing bolts to the manufacturer's torque specifications, following the correct tightening sequence to ensure proper sealing. After the housing is assembled, install the external components, such as the PTO shaft, shift levers, and hydraulic lines. Ensure that all components are properly connected and tightened. Fill the transmission with the recommended type and quantity of transmission oil. Before starting the tractor, check for any leaks or abnormalities. Start the tractor and allow it to idle for a few minutes, checking for any unusual noises or vibrations. Test the transmission through all gears to ensure that it is operating smoothly and correctly. If any problems are detected, shut down the tractor and investigate the cause before continuing operation.
The hydraulic pump is the heart of your John Deere 1120's hydraulic system, providing the necessary pressure to operate implements and other hydraulic functions. A properly functioning pump is crucial for efficient and reliable operation. Regular inspection and maintenance are essential to ensure its longevity and prevent costly repairs. Neglecting pump maintenance can lead to decreased performance, increased wear on other hydraulic components, and even complete system failure. Always consult the John Deere 1120 service manual for specific torque specifications and recommended lubricants.
Before servicing the hydraulic pump, always relieve the pressure in the hydraulic system. This is typically done by cycling all hydraulic functions, such as lifting the three-point hitch or operating the remote hydraulic valves, until no further movement occurs. Disconnect the battery's negative terminal to prevent accidental starting of the engine during the service procedure. Proper lockout/tagout procedures are crucial for your safety. Remember to use safety glasses and gloves when working with hydraulic fluid, as it can be harmful to skin and eyes.
To remove the hydraulic pump, first disconnect the inlet and outlet lines. Be prepared for some hydraulic fluid to spill, so have a container ready to catch it. Carefully inspect the lines and fittings for any signs of wear, damage, or corrosion. Replace any damaged components before reinstalling the pump. After disconnecting the lines, unbolt the pump from its mounting bracket. Be sure to note the orientation of the pump for proper reinstallation. Once the pump is removed, thoroughly clean the exterior to allow for easier inspection of any external damages.
When inspecting the hydraulic pump, look for signs of leakage, cracks, or damage to the housing. Check the shaft for any bends or excessive play. If you suspect internal damage, the pump should be disassembled for a more thorough inspection. Disassembly requires specialized tools and knowledge, so if you're not comfortable performing this task, it's best to take the pump to a qualified hydraulic repair shop. Remember to document the disassembly process and take photos to assist with reassembly. Keep all parts clean and organized during disassembly.
Reassembly of the hydraulic pump should be done with great care, following the manufacturer's instructions precisely. Use new seals and gaskets to prevent leaks. Ensure all components are properly aligned and torqued to the specified values. After reassembling the pump, test it on a hydraulic test bench to ensure it meets the required pressure and flow specifications. If the pump fails the test, further diagnosis and repair are necessary. Finally, reinstall the hydraulic pump to the tractor and double check to make sure all lines and connections are tightened to the correct torque specifications.
Hydraulic valves control the flow of hydraulic fluid, directing it to various components such as cylinders and motors. Proper valve function is essential for precise and controlled operation of implements. Dirty or malfunctioning valves can cause erratic movement, slow response times, and even complete failure of hydraulic functions. Regular cleaning and inspection are crucial to maintain optimal valve performance.
Before servicing any hydraulic valve, it's critical to relieve the system pressure and disconnect the battery's negative terminal. This prevents accidental activation of hydraulic functions and ensures your safety. Identify the valve you need to service and disconnect all hydraulic lines connected to it. Be prepared for some fluid spillage and use a suitable container to collect it. Always label the lines to ensure correct reassembly. Take pictures if needed for future reference.
Remove the valve from the tractor and clean its exterior thoroughly. Inspect the valve body for any signs of cracks or damage. Check the spools for smooth movement. If a spool is sticking or binding, it may indicate contamination or damage. Disassemble the valve carefully, noting the location of each component. Pay close attention to the orientation of springs, seals, and other small parts.
Clean all valve components with a suitable solvent. Inspect the spools and valve body for any signs of wear, scratches, or corrosion. Replace any worn or damaged parts. Check the seals for cracks, tears, or hardening. Replace all seals during reassembly to prevent leaks. Use new o-rings and gaskets as needed. Lubricate the valve components with hydraulic oil before reassembly to ensure smooth operation.
Reassemble the valve carefully, following the manufacturer's instructions. Ensure all components are properly aligned and seated. Tighten all fasteners to the specified torque values. After reassembling the valve, test it on a hydraulic test bench to verify its proper function. Check for leaks and smooth spool movement. If the valve fails the test, further diagnosis and repair are necessary. Once the valve is tested and working correctly, reinstall it on the tractor and reconnect the hydraulic lines. Make sure the lines are connected to the right connections and there are no leaks.
Hydraulic cylinders convert hydraulic pressure into linear motion, powering various implements and functions on your John Deere 1120. Over time, cylinder seals can wear, leading to leaks and reduced performance. Damaged cylinder rods can also cause problems. Regular inspection and maintenance are essential to ensure reliable cylinder operation. Ignoring cylinder issues can lead to inefficient operation and potential damage to other hydraulic components.
Before servicing a hydraulic cylinder, relieve the system pressure and disconnect the hydraulic lines connected to the cylinder. Support the cylinder properly to prevent it from falling. Loosen the gland nut or retaining bolts, but do not remove them completely. This will allow you to relieve any remaining pressure within the cylinder. Carefully remove the gland nut or retaining bolts and slide the cylinder rod out of the cylinder barrel. Be prepared for some fluid spillage.
Inspect the cylinder rod for any signs of damage, such as bends, scratches, or corrosion. If the rod is damaged, it may need to be repaired or replaced. Inspect the cylinder barrel for any internal damage or wear. Clean the barrel thoroughly with a suitable solvent. Remove the seals from the cylinder rod and piston. Inspect the seals for any signs of wear, cracks, or tears. Replace all seals with new ones.
Lubricate the new seals with hydraulic oil before installing them onto the cylinder rod and piston. Install the piston onto the cylinder rod and tighten the retaining nut to the specified torque value. Carefully slide the cylinder rod back into the cylinder barrel. Install the gland nut or retaining bolts and tighten them to the specified torque value. Connect the hydraulic lines to the cylinder and test its operation. Check for leaks and smooth movement. Ensure there are no leaks and that the equipment operates smoothly.
If the cylinder leaks after reassembly, recheck the seals and connections. Make sure all components are properly installed and tightened. If the cylinder continues to leak, there may be damage to the cylinder barrel or rod that requires further repair or replacement. Always use genuine John Deere parts to ensure proper fit and performance. After cylinder maintenance it's vital to test the cylinder through its entire range to be certain there are no issues or leaks.
Maintaining clean hydraulic oil and replacing the hydraulic filter at recommended intervals are crucial for the longevity and performance of your John Deere 1120's hydraulic system. Dirty oil and a clogged filter can restrict flow, reduce pressure, and cause premature wear on hydraulic components. Regular oil and filter changes prevent these issues and ensure optimal system operation. Neglecting this service can lead to costly repairs down the road.
Before changing the hydraulic oil and filter, warm up the hydraulic system by running the tractor for a few minutes. This will help to suspend contaminants in the oil and ensure a more thorough drain. Position a suitable container under the drain plug to catch the old oil. Remove the drain plug and allow the oil to drain completely. Once the oil has drained, replace the drain plug and tighten it to the specified torque value. Be sure to consult the John Deere 1120 service manual for the correct location of the drain plug and the proper torque specification.
Locate the hydraulic filter and remove it using a filter wrench. Be prepared for some oil spillage. Clean the filter mounting surface. Lubricate the gasket of the new filter with clean hydraulic oil. Install the new filter and tighten it according to the manufacturer's instructions. Do not overtighten the filter, as this can damage the gasket and cause leaks. Ensure the filter is properly sealed against the mounting surface.
Fill the hydraulic reservoir with the recommended type and amount of hydraulic oil. Consult your John Deere 1120 service manual for the correct oil specification and capacity. After filling the reservoir, start the engine and run it at a low idle. Cycle all hydraulic functions to bleed any air from the system. Check the oil level and add more oil if necessary. Inspect the filter and drain plug for any leaks. It is always a good idea to recheck oil levels after the first couple of hours of operation.
Dispose of the used hydraulic oil and filter properly. Most auto parts stores and service centers will accept used oil for recycling. Do not pour used oil down the drain or onto the ground. Doing so can contaminate the environment. Proper disposal of hazardous waste is essential for protecting our environment. A little effort in proper waste disposal goes a long way in protecting our waterways.
Hydraulic problems can manifest in various ways, from slow implement response to complete system failure. Identifying the root cause of the problem is essential for effective repair. A systematic approach to troubleshooting can save time and prevent unnecessary repairs. Consulting the John Deere 1120 service manual is always the first step in diagnosing any hydraulic issue. Understanding the hydraulic system's components and their functions is crucial for effective troubleshooting.
If you're experiencing slow implement response, start by checking the hydraulic oil level. Low oil levels can cause cavitation and reduced pump output. Check the hydraulic filter for clogging. A clogged filter can restrict flow and reduce pressure. Inspect the hydraulic lines for any kinks or restrictions. These can also impede flow. If the oil level and filter are good, check the hydraulic pump pressure. A weak pump may not be able to generate sufficient pressure to operate the implements properly. If the pump is found to be defective, it should be serviced or replaced as described above.
If you're experiencing hydraulic leaks, identify the source of the leak. Check the cylinder seals, valve seals, and hose connections. Replace any worn or damaged seals. Tighten any loose connections. If the leak is coming from a crack in a component, the component may need to be repaired or replaced. Pay close attention to high pressure areas where leaks can be more substantial and potentially dangerous. If the leak is excessive, stop the engine immediately and correct the issue before continuing operation.
If you're experiencing erratic implement movement, check the hydraulic valve spools for binding or sticking. Clean or replace any damaged valve components. Check the hydraulic cylinders for internal leaks. Internal leaks can cause erratic movement and reduced power. If the cylinders are leaking internally, they should be rebuilt or replaced. Be sure to thoroughly inspect the lines and fittings for damage. If you are unsure, consult a professional.
Before attempting any major repairs, consult the John Deere 1120 service manual for detailed troubleshooting procedures. The manual provides specific diagnostic steps and repair instructions for various hydraulic issues. If you're not comfortable performing the repairs yourself, take the tractor to a qualified mechanic. Attempting repairs without the proper knowledge and tools can lead to further damage and injury. Remember, safety should always be your top priority when working on hydraulic systems. Always consult a professional if you are unsure about how to proceed.
The proper adjustment of the brakes on your John Deere 1120 is crucial for safe and efficient operation. Unevenly adjusted brakes can lead to pulling to one side during braking, increased stopping distances, and premature wear of brake components. Before beginning any adjustment procedure, ensure the tractor is parked on a level surface, the engine is off, and the parking brake is securely engaged. Always consult the tractor's operator manual for specific instructions and recommended tolerances related to your model's brake system. Incorrect adjustment can compromise braking performance and potentially create hazardous conditions during operation.
To adjust the brakes, typically you will find adjustment mechanisms, usually turnbuckles or linkage arms, located near the brake pedals or on the brake assemblies themselves. Loosen the locknut or retaining hardware on the adjuster to allow for movement. Adjust the linkage until the desired pedal travel is achieved and the brakes engage evenly. Refer to the operator manual for the precise amount of free play (the distance the pedal moves before the brakes start to engage) that is recommended. After making the adjustment, securely tighten the locknut or retaining hardware to prevent the adjuster from moving out of position.
After adjusting the brakes, perform a test drive in a safe area to ensure they are functioning correctly. Pay close attention to the braking response, pedal feel, and any signs of pulling or uneven braking. If any issues are detected, re-check the adjustments and make further corrections as needed. Regular inspection and adjustment of the brakes are essential for maintaining optimal braking performance and ensuring the safety of the operator and the equipment. Remember to consult a qualified technician if you are unsure about any aspect of the brake adjustment procedure.
Worn brake linings are a common cause of reduced braking performance. Over time, the friction material on the brake shoes wears down, resulting in less effective braking and potentially damaging the brake drums or rotors. Signs of worn brake linings include excessive brake pedal travel, a grinding or squealing noise when braking, and a noticeable decrease in stopping power. If you observe any of these symptoms, it's important to inspect the brake linings and replace them if they are worn beyond the manufacturer's recommended wear limits.
Replacing brake linings requires removing the brake assembly from the tractor. This typically involves disconnecting the brake linkage, removing the wheel, and disassembling the brake components. Before disassembling the brake assembly, carefully note the position and orientation of all parts to ensure proper reassembly. Clean all components thoroughly with brake cleaner to remove dirt, grease, and brake dust. This will allow for a better inspection and prevent contamination of the new brake linings. Make sure you use proper safety equipment, such as gloves and eye protection, when working with brake components.
Install the new brake linings onto the brake shoes or pads, following the manufacturer's instructions. Ensure that the linings are properly aligned and secured to the shoes. After installing the new linings, reassemble the brake assembly, taking care to correctly position all parts. Adjust the brakes according to the manufacturer's recommendations, ensuring proper pedal travel and even brake engagement. After completing the brake lining replacement, perform a thorough test drive to ensure the brakes are functioning correctly. Inspect the brakes regularly and replace the linings as needed to maintain optimal braking performance and safety.
The brake cylinders are vital components of the braking system, responsible for converting hydraulic pressure into mechanical force to apply the brakes. Over time, the seals and internal components of the brake cylinders can wear out or become damaged, leading to leaks and reduced braking efficiency. Signs of brake cylinder problems include a spongy or soft brake pedal, brake fluid leaks around the cylinders, and uneven braking. If you notice any of these issues, it's important to inspect and service the brake cylinders as needed.
Servicing the brake cylinders typically involves disassembling them, inspecting the internal components for wear or damage, and replacing any worn or damaged parts. Begin by disconnecting the brake lines from the cylinder and removing the cylinder from the tractor. Carefully disassemble the cylinder, noting the position and orientation of all parts. Clean all components thoroughly with brake cleaner and inspect the cylinder bore, piston, and seals for wear, corrosion, or damage. Replace any worn or damaged parts with new components that meet the manufacturer's specifications.
Reassemble the brake cylinder, ensuring that all parts are properly lubricated with brake fluid and that the seals are correctly installed. After reassembling the cylinder, bleed the brake system to remove any air that may have entered during the service procedure. Adjust the brakes according to the manufacturer's recommendations, ensuring proper pedal travel and even brake engagement. Regular inspection and service of the brake cylinders are essential for maintaining optimal braking performance and ensuring the safety of the operator and the equipment. If you are unfamiliar with brake cylinder service procedures, consult a qualified technician.
Brake bleeding is the process of removing air from the hydraulic brake system. Air in the brake lines can compress, reducing the hydraulic pressure transmitted to the brake cylinders and resulting in a spongy or soft brake pedal. This can significantly reduce braking efficiency and potentially lead to brake failure. Brake bleeding is necessary after performing any service that introduces air into the brake system, such as replacing brake lines, brake cylinders, or brake linings.
The most common method of brake bleeding involves using a bleeder screw located on each brake cylinder. Start by locating the bleeder screw and attaching a clear hose to it. Submerge the other end of the hose in a container filled with brake fluid. This prevents air from being drawn back into the system during the bleeding process. Have an assistant slowly depress the brake pedal while you open the bleeder screw. Observe the brake fluid flowing through the hose. Continue to open and close the bleeder screw, allowing fluid to flow through the hose until no more air bubbles are visible.
After bleeding each brake cylinder, check the brake pedal feel. The pedal should feel firm and solid. If the pedal still feels spongy or soft, repeat the bleeding procedure. Ensure that the brake fluid reservoir is kept full during the bleeding process to prevent air from being drawn into the system. After completing the brake bleeding, tighten the bleeder screws and check for any leaks. Perform a test drive in a safe area to ensure the brakes are functioning correctly. Regular brake bleeding is essential for maintaining optimal braking performance and ensuring the safety of the operator and the equipment.
The steering gearbox on the John Deere 1120 is a critical component, translating the operator's input at the steering wheel into the directional movement of the front wheels. Proper maintenance and occasional service are essential for safe and efficient operation of the tractor. Before beginning any service on the steering gearbox, always disconnect the battery to prevent accidental starting and ensure the tractor is securely supported to prevent movement. Carefully inspect the gearbox housing for any signs of damage, such as cracks or leaks, as these indicate potential problems that require immediate attention. If any damage is found, further investigation is needed. Finally, consult the parts manual to ensure you have the appropriate seal or tools.
To begin servicing the steering gearbox, start by draining the old lubricant. Locate the drain plug on the bottom of the gearbox housing and carefully remove it, allowing the lubricant to drain completely into a suitable container. Inspect the drained lubricant for any signs of metal shavings or contamination, which could indicate internal wear or damage. After the lubricant has drained, thoroughly clean the drain plug and reinstall it, ensuring it is properly tightened to prevent leaks. If the lubricant is of low quality, or appears to be filled with fragments, the inner workings should be looked at.
Next, inspect the steering gearbox for excessive play or looseness. This can be done by moving the steering wheel back and forth while observing the movement of the pitman arm. Excessive play indicates wear in the internal gears or bearings of the gearbox, and may require adjustment or replacement of worn parts. Refer to the service manual for detailed instructions on adjusting the steering gearbox to minimize play. If adjustment is not possible or the play persists, the gearbox may need to be disassembled for inspection and repair. Properly diagnosing the issue is important to avoid further problems.
If disassembly is required, carefully follow the instructions in the service manual. It is important to document the location and orientation of all parts as they are removed to ensure proper reassembly. Thoroughly clean all parts with a suitable solvent and inspect them for wear, damage, or corrosion. Pay close attention to the gears, bearings, and seals, as these are common wear points in the steering gearbox. Replace any worn or damaged parts with new ones, using only genuine John Deere parts or approved equivalents to ensure proper fit and performance. Once the components are replaced, the gearbox can be reassembled.
After reassembling the steering gearbox, refill it with the recommended type and quantity of lubricant. Refer to the service manual for the correct lubricant specification and filling procedure. Overfilling or using the wrong type of lubricant can damage the gearbox. Once the gearbox is filled, check for leaks around the drain plug and input/output shafts. Operate the steering wheel through its full range of motion and listen for any unusual noises or binding. If any problems are detected, re-inspect the gearbox and make any necessary adjustments. Finally, be sure the tractor is properly started to test the functionality of the repair.
The steering linkage connects the steering gearbox to the front wheels, transmitting the steering motion and allowing the operator to control the direction of the tractor. Regular inspection and maintenance of the steering linkage are essential for maintaining proper steering control and preventing accidents. Before beginning any service, make sure the tractor is parked on a level surface and the engine is turned off. Chock the rear wheels to prevent the tractor from rolling. Also be sure to familiarize yourself with the locations of linkage.
Start by visually inspecting all components of the steering linkage, including the tie rods, drag link, ball joints, and steering arms. Look for any signs of wear, damage, or corrosion, such as cracks, bends, or excessive play. Pay particular attention to the ball joints, as these are common wear points. Grasp each ball joint and attempt to move it by hand. If there is excessive play or looseness, the ball joint should be replaced. Any damaged or excessively worn component of the steering linkage should be replaced immediately to prevent steering failure. Make sure to inspect the threads of any bolts or nuts used.
Next, check the alignment of the front wheels. Misalignment can cause excessive tire wear, poor handling, and increased steering effort. Use a tape measure or alignment tool to measure the distance between the front wheels at the front and rear of the tires. The difference between these measurements should be within the specifications listed in the service manual. If the front wheels are not properly aligned, adjust the tie rods as necessary to correct the alignment. Consult the service manual for detailed instructions on adjusting the tie rods and setting the front wheel toe-in. Record the adjustments for further verification.
After adjusting the tie rods, lubricate all grease fittings on the steering linkage. Use a grease gun to inject grease into each fitting until fresh grease appears, pushing out any old grease or contaminants. Proper lubrication is essential for reducing friction and wear in the steering linkage. Wipe off any excess grease to prevent dirt and debris from accumulating. Regularly lubricating the steering linkage will help to extend the life of the components and maintain smooth, responsive steering. Be sure to properly dispose of any cleaning solutions after maintenance.
Finally, after completing all service procedures, test the steering system to ensure it is functioning properly. Start the engine and slowly drive the tractor forward, making sure the steering is responsive and predictable. Check for any unusual noises or vibrations in the steering system. If any problems are detected, re-inspect the steering linkage and make any necessary adjustments or repairs. If there is no issue then you have successfully repaired the linkage.
If your John Deere 1120 is equipped with power steering, additional maintenance is required to ensure its proper operation. The power steering system uses hydraulic pressure to assist the operator in steering the tractor, reducing steering effort and improving maneuverability. Regularly check the power steering fluid level in the reservoir. The fluid level should be within the specified range, as indicated on the reservoir. Low fluid levels can cause the power steering system to malfunction, resulting in increased steering effort or complete loss of power steering. Remember to turn off the tractor before checking the fluid.
Inspect the power steering hoses and fittings for leaks or damage. Replace any damaged hoses or fittings immediately to prevent fluid loss and maintain proper power steering pressure. Check the power steering pump for any unusual noises or vibrations. Unusual noises can indicate wear or damage in the pump. If the pump is noisy or vibrates excessively, it should be inspected and repaired or replaced as needed. Ensure hoses are tightened correctly and not rubbing on anything else.
If the power steering system is not functioning properly, check the power steering belt for wear or damage. A worn or damaged belt can slip, reducing the amount of power delivered to the power steering pump. Adjust or replace the belt as needed to ensure proper tension and prevent slippage. Regularly lubricating the steering system will help to extend the life of the components and maintain smooth, responsive steering. The pump also relies on power to create a fluid.
Periodically flush the power steering system to remove any contaminants or debris that may have accumulated in the fluid. Refer to the service manual for the recommended flushing procedure and fluid type. Flushing the system can help to prevent damage to the power steering pump and other components. Once the tractor is fixed be sure to properly dispose of any cleaning solutions after maintenance.
After completing all service procedures, test the power steering system to ensure it is functioning properly. Start the engine and turn the steering wheel from lock to lock. The steering should be smooth and effortless, without any binding or hesitation. If any problems are detected, re-inspect the power steering system and make any necessary adjustments or repairs. If there is still an issue, try to reference the service manual again.
The front axle of your John Deere 1120 is a critical component responsible for steering and supporting the front of the tractor. Regular maintenance and timely repairs are crucial for ensuring optimal performance and preventing costly breakdowns. Before attempting any front axle service, it is imperative to consult the complete John Deere 1120 service manual for specific instructions, torque specifications, and safety precautions. Improper procedures can lead to damage to the tractor and potentially cause serious injury. Always disconnect the battery and use appropriate jack stands to securely support the tractor before beginning any work.
Inspecting the front axle for wear and damage is an important preventative measure. Look for signs of leaks around the axle seals, kingpins, and steering components. Check the kingpin bushings for excessive play, which can lead to sloppy steering and premature wear. Inspect the tie rod ends and steering linkage for looseness or damage. Regularly greasing the front axle components is essential for proper lubrication and extending the life of the bushings and bearings. Use a high-quality lithium-based grease and follow the greasing schedule outlined in the service manual.
If you notice any problems with the front axle, such as excessive play, leaks, or unusual noises, it's important to address them promptly. Replacing worn kingpin bushings, seals, or tie rod ends can prevent further damage and ensure safe operation. When disassembling the front axle, be sure to carefully mark and label all parts to ensure proper reassembly. Use the correct tools and torque specifications when tightening fasteners to avoid damaging the components. If you are not comfortable performing these repairs yourself, it is always best to consult with a qualified tractor mechanic.
The rear axle assembly on the John Deere 1120 transmits power from the transmission to the rear wheels, propelling the tractor forward. It's a robust system, but it's still subject to wear and tear over time. Regular checks of the rear axle oil level and condition are crucial. Low oil levels can lead to overheating and damage to the gears and bearings. Contaminated oil can also accelerate wear and reduce the efficiency of the axle. Always use the recommended type of oil specified in the service manual and adhere to the recommended oil change intervals.
When inspecting the rear axle, carefully listen for any unusual noises, such as grinding, whining, or clicking. These noises can indicate worn gears, bearings, or other internal damage. Also, check for leaks around the axle seals. Leaks not only waste oil but can also contaminate the brakes. If you suspect any problems with the rear axle, it's important to have it inspected by a qualified mechanic. Ignoring these symptoms can lead to more serious damage and costly repairs down the road.
Servicing the rear axle typically involves draining the oil, inspecting the gears and bearings, and replacing any worn or damaged parts. Special tools and knowledge are often required to properly disassemble and reassemble the rear axle. If you are not experienced in tractor repair, it's best to leave this type of work to a professional. Remember to use the correct torque specifications when tightening fasteners and to follow the service manual instructions carefully.
The final drive on the John Deere 1120 provides the final reduction in speed and increase in torque before power is delivered to the wheels. It's a critical component for maximizing the tractor's pulling power. Proper maintenance of the final drive is essential for ensuring long-lasting performance. The final drive shares its oil reservoir with the transmission in most John Deere 1120 models, so maintaining the transmission fluid according to the maintenance schedule is important for the health of the final drive as well.
Regularly inspect the final drive housings for any signs of leaks. Leaks around the seals can indicate wear or damage and should be addressed promptly to prevent oil loss and potential damage to the gears and bearings. Listen for any unusual noises coming from the final drive, such as grinding, whining, or clicking. These noises can indicate worn components and should be investigated. Remember to check the breather cap on the final drive to ensure it is clean and free of obstructions. A clogged breather can cause pressure to build up inside the final drive, leading to leaks and damage.
When servicing the final drive, it's crucial to follow the instructions in the service manual carefully. Disassembly and reassembly of the final drive require specialized tools and knowledge. Be sure to use the correct torque specifications when tightening fasteners and to replace any worn or damaged parts with genuine John Deere parts. If you are not comfortable performing these repairs yourself, it's best to consult with a qualified tractor mechanic who has experience working on John Deere tractors. Remember, proper maintenance and timely repairs are essential for ensuring the long-lasting performance of your John Deere 1120.
Proper tire maintenance is crucial for optimal tractor performance, safety, and longevity. Regularly inspecting your tires for wear, damage, and proper inflation is paramount. Underinflated tires can lead to increased fuel consumption, reduced traction, and accelerated tire wear, while overinflated tires can result in a harsh ride and increased susceptibility to impact damage. Refer to the tire sidewall or your John Deere 1120 operator's manual for the recommended inflation pressure for your specific tire size and application. A calibrated tire pressure gauge is an essential tool for ensuring accurate readings.
When inspecting your tires, pay close attention to the tread depth and look for any signs of cuts, bulges, or embedded objects. Uneven tread wear can indicate alignment issues or improper inflation. Small cuts and abrasions can often be repaired, but larger damage may necessitate tire replacement. Removing any embedded objects, such as nails or glass, promptly can prevent further damage and potential air leaks. Always use appropriate tire repair techniques and materials if attempting a repair yourself. If in doubt, consult a qualified tire service professional.
For more extensive tire repairs, such as patching or tube replacement, it is highly recommended to seek the services of a qualified tire technician. Attempting complex repairs without the proper tools and expertise can be dangerous and may further damage the tire. When replacing tires, always choose tires that meet or exceed the original equipment specifications for your John Deere 1120. Consider the type of work you typically perform with your tractor when selecting new tires, as different tread patterns and tire compounds are optimized for different applications, such as plowing, mowing, or general utility work.
Tire rotation is another vital aspect of tire maintenance. Rotating your tires periodically helps to distribute wear evenly across all tires, extending their overall lifespan. The recommended rotation pattern may vary depending on your tractor's configuration and tire type, so consult your John Deere 1120 service manual for specific instructions. Remember to always deflate, unmount the wheel and tire as a single unit, and remount before reinflating to the recommended pressure.
Proper wheel alignment is critical for ensuring optimal steering response, tire wear, and overall tractor handling. Misalignment can lead to excessive tire wear, especially on the front tires, as well as increased fuel consumption and reduced steering precision. A visual inspection can often reveal obvious signs of misalignment, such as uneven tire wear patterns or the tractor pulling to one side while driving straight. However, a more precise alignment check requires specialized equipment and expertise.
The front wheel alignment on the John Deere 1120 typically involves adjusting the toe-in or toe-out. Toe-in refers to the distance between the front of the tires being slightly closer together than the rear, while toe-out is the opposite. The specific toe-in or toe-out specification will be detailed in your service manual. Adjustments are typically made by loosening the tie rod ends and rotating them to lengthen or shorten the tie rods. It's crucial to make small, incremental adjustments and recheck the alignment after each adjustment to avoid overcorrection.
Before attempting any wheel alignment adjustments, ensure that the steering system components are in good condition. Inspect the tie rod ends, steering linkage, and wheel bearings for any signs of wear or looseness. Any worn or damaged components should be replaced before performing the alignment. Worn parts can throw off an alignment and could lead to repeat corrections or premature tire wear.
If you lack experience in performing wheel alignment adjustments, it is highly recommended to seek the services of a qualified mechanic with access to the necessary alignment equipment. Attempting to adjust the alignment without the proper tools and knowledge can result in further damage to the steering system or incorrect alignment, leading to even more severe problems. A professional alignment will ensure that your tractor handles properly and that your tires wear evenly, saving you money in the long run.
Before starting your John Deere 1120 each day, a quick visual inspection can save you significant headaches down the road. Walk around the tractor, paying close attention to fluid levels and potential leaks. Check the engine oil dipstick to ensure the oil level is within the acceptable range. Similarly, inspect the coolant reservoir or radiator for proper coolant levels. Look for any signs of fluid leaks underneath the tractor, such as oil, coolant, or hydraulic fluid. Addressing these issues early prevents more costly repairs later on.
Don't forget the tires! Ensure all tires are properly inflated to the manufacturer's recommended pressure. Underinflated tires can lead to premature wear and tear, reduced fuel efficiency, and even potential tire failure. Check the tires for any signs of damage, such as cuts, bulges, or embedded objects. Remove any debris stuck in the tire treads. A properly inflated and well-maintained tire significantly enhances the tractor's performance and safety.
Once a week, conduct a more thorough inspection of your John Deere 1120. This includes checking the air filter element. A dirty air filter restricts airflow to the engine, reducing power and fuel efficiency. Depending on the operating conditions, you may need to clean or replace the air filter more frequently. Inspect the battery terminals for corrosion and clean them as necessary. Ensure the battery cables are securely connected to prevent starting problems.
Take the time to grease all the lubrication points on the tractor. Consult your operator's manual for the location of these points, which typically include steering linkages, front axle components, and PTO shaft bearings. Proper lubrication reduces friction and wear, extending the life of these critical components. Use the correct type of grease as recommended by John Deere. Regular greasing is a crucial step in preventing premature failure of moving parts.
Monthly checks should include inspecting the hydraulic system. Check the hydraulic fluid level and look for any signs of leaks around hoses, fittings, and cylinders. Monitor the operation of hydraulic functions, such as the loader and three-point hitch, for smooth and responsive movement. If you notice any sluggishness or jerky operation, it could indicate a problem with the hydraulic system. Ensure proper hydraulic system function for reliable equipment operation.
Inspect the condition of all belts and hoses on the engine. Look for cracks, fraying, or signs of wear. Replace any belts or hoses that are damaged or show signs of deterioration. A broken belt or hose can lead to engine overheating or other serious problems. Check the condition of the radiator fins and clean them if necessary to ensure proper airflow. Maintaining the cooling system prevents overheating and protects the engine from damage.
Annually, a comprehensive service is essential to maintain the John Deere 1120's performance and longevity. This should include changing the engine oil and filter, the hydraulic oil and filter, and the fuel filter. Use the correct type of oil and filters as specified by John Deere. Consider taking an oil sample for analysis, which can reveal potential problems with the engine or hydraulic system. Regular oil changes are essential for optimal engine and hydraulic system performance.
A thorough inspection of the brake system is also important. Check the brake linings for wear and adjust the brakes as necessary. Inspect the brake lines and cylinders for leaks. Replace any worn or damaged components. Proper brake function is critical for safety, especially when operating on slopes or in traffic. Review the electrical system, checking wiring for damage or degradation and ensuring all lights function properly. Finally, consider having a professional perform a more detailed diagnostic check to identify any potential issues before they become major problems.
Engine problems are a common headache for tractor owners, and diagnosing the root cause requires a systematic approach. Start by checking the obvious: fuel level, fuel lines for blockages or leaks, and air filter condition. A dirty air filter can significantly restrict airflow, leading to poor combustion and reduced power. Next, examine the engine oil level and condition. Low oil or contaminated oil can cause severe engine damage, so it's crucial to address these issues promptly. Listen carefully for any unusual noises, such as knocking, hissing, or rattling, as these can indicate specific problems within the engine.
If the basic checks don't reveal the problem, proceed to more advanced troubleshooting steps. Check the fuel injectors for proper operation. Faulty injectors can deliver too much or too little fuel, leading to rough running or starting difficulties. Also, evaluate the ignition system (if your 1120 has a gasoline engine) or the glow plugs (if it's a diesel engine) for proper functioning. A weak spark or faulty glow plugs can make starting the engine challenging, especially in cold weather. Finally, a compression test can reveal internal engine problems, such as worn piston rings or damaged valves.
The transmission is the heart of your tractor's drivetrain, and any issues with it can significantly impact its performance. Slipping gears, difficulty shifting, or unusual noises are common signs of transmission problems. Begin by checking the transmission oil level and condition. Low oil or contaminated oil can lead to premature wear and failure of transmission components. Examine the shift linkage for proper adjustment. Misaligned or worn linkage can make shifting difficult or impossible.
If the external checks don't resolve the issue, internal transmission problems may be the cause. Worn synchronizers, damaged gears, or broken bearings can all contribute to transmission malfunctions. Diagnosing these issues often requires disassembling the transmission, which is best left to experienced technicians with specialized tools. Also consider if you have the Hi-Lo option. If so, make sure it is engaging properly as well.
The hydraulic system powers many of the tractor's functions, including the loader, three-point hitch, and power steering. Common hydraulic problems include slow or weak operation, erratic movement, or leaks. Start by checking the hydraulic fluid level and condition. Low fluid or contaminated fluid can reduce hydraulic performance and damage system components. Inspect the hydraulic lines and hoses for leaks or damage. Even a small leak can lead to significant fluid loss and reduced pressure.
Further troubleshooting involves checking the hydraulic pump for proper operation. A worn or damaged pump may not be able to generate sufficient pressure. Inspect the hydraulic cylinders for leaks or damage. Internal leaks within the cylinders can cause them to lose pressure and operate slowly. Finally, check the control valves for proper functioning. Stuck or malfunctioning valves can prevent hydraulic fluid from flowing correctly.
The electrical system is essential for starting the engine, operating lights, and powering various accessories. Common electrical problems include a dead battery, dim lights, or a non-starting engine. Begin by checking the battery voltage and connections. A weak battery or corroded connections can prevent the engine from starting. Inspect the fuses and circuit breakers for any blown fuses or tripped breakers. Replacing a blown fuse or resetting a tripped breaker may solve the problem.
If the basic checks don't reveal the issue, further troubleshooting may be necessary. Check the alternator or generator for proper charging. A faulty charging system can prevent the battery from staying charged. Inspect the wiring harness for any damaged or corroded wires. Damaged wires can cause short circuits or open circuits, leading to various electrical problems. Finally, check the starter motor for proper operation. A faulty starter motor may not be able to turn the engine over.
Properly functioning brakes are crucial for safety. Brake problems include weak braking, uneven braking, or squealing noises. Start by checking the brake fluid level and condition. Low fluid or contaminated fluid can reduce braking performance. Inspect the brake lines and hoses for leaks or damage. Air in the brake lines can also cause weak braking. You may need to bleed the system.
Further troubleshooting involves inspecting the brake pads or shoes for wear. Worn brake pads or shoes will reduce braking effectiveness. Check the brake drums or rotors for damage or wear. Scored or damaged drums or rotors can cause uneven braking or squealing noises. Also, make sure the brake linkages are properly adjusted.
Proper steering is essential for safe and efficient operation. Steering problems include hard steering, loose steering, or wandering. Start by checking the power steering fluid level and condition (if equipped). Low fluid or contaminated fluid can reduce power steering performance. Inspect the steering linkage for wear or damage. Worn or loose linkage can cause loose steering.
Also, check the front wheel alignment. Misaligned front wheels can cause hard steering or wandering. Inspect the tires for proper inflation and wear. Uneven tire wear can contribute to steering problems. Finally, inspect the steering gearbox for wear or damage. A worn or damaged gearbox can cause hard steering or loose steering.
Understanding torque specifications is paramount when servicing your John Deere 1120 tractor. Improperly torqued fasteners can lead to a multitude of problems, ranging from minor leaks to catastrophic engine or component failure. Always consult this manual before tightening any bolt, nut, or fitting on your tractor. Remember that torque specifications are typically given for clean, dry threads unless otherwise specified; lubricating threads can significantly alter the applied torque, potentially leading to over-tightening and damage. Use a calibrated torque wrench for accurate results and ensure that you are using the correct size socket or wrench to avoid slippage or damage to the fastener.
The engine is the heart of your John Deere 1120, and its proper functioning relies heavily on correctly torqued components. Cylinder head bolts, for example, require specific torque values and tightening sequences to ensure a proper seal and prevent leaks. Similarly, the connecting rod bolts and main bearing cap bolts must be tightened according to the manufacturer's specifications to maintain proper bearing clearances and prevent engine damage. Ignoring these torque requirements can result in reduced engine performance, increased wear and tear, and potentially complete engine failure. When working on the engine, always refer to the torque specifications for each individual component to ensure proper assembly and longevity.
Furthermore, components such as the intake manifold and exhaust manifold also have specific torque requirements to ensure proper sealing and prevent leaks. These components are often subjected to high temperatures and vibrations, which can loosen improperly tightened fasteners over time. Similarly, the fuel injectors and other fuel system components must be properly torqued to prevent fuel leaks and maintain optimal engine performance. Careful attention to detail and adherence to the recommended torque values are essential when working on any part of the engine to ensure reliable operation and prevent costly repairs.
The transmission is responsible for transferring power from the engine to the wheels, and its components must be precisely assembled to ensure smooth and reliable operation. The transmission housing bolts, gear retaining nuts, and shaft bearing caps all have specific torque requirements that must be followed to prevent leaks and maintain proper gear alignment. Over-tightening can distort the housing or damage the gears, while under-tightening can lead to leaks and premature wear. Always use a calibrated torque wrench and refer to the torque specifications in this manual when working on the transmission to ensure proper assembly and prevent costly repairs.
In addition to the internal components of the transmission, the external linkages and control mechanisms also require specific torque values. The shift lever assembly, clutch linkage, and PTO engagement mechanism must be properly tightened to ensure smooth and precise operation. Loose or improperly tightened linkages can lead to difficult shifting, clutch slippage, or PTO engagement problems. Therefore, it is essential to pay attention to the torque specifications for all transmission components, both internal and external, to ensure reliable operation and prevent performance issues.
The hydraulic system on your John Deere 1120 powers various functions, including the power steering, three-point hitch, and remote hydraulic outlets. The hydraulic pump mounting bolts, valve body bolts, and cylinder rod end bolts all have specific torque requirements to ensure proper sealing and prevent leaks. Hydraulic fluid leaks can lead to reduced system performance, increased wear on components, and potentially hazardous conditions. Always use new O-rings and sealing washers when reassembling hydraulic components and tighten fasteners to the recommended torque values.
Furthermore, the hydraulic lines and fittings must be properly tightened to prevent leaks and maintain system pressure. Over-tightening hydraulic fittings can damage the threads or distort the fitting, leading to leaks. Under-tightening can also result in leaks, especially in systems with high operating pressures. Use the correct size wrenches and torque the fittings to the specified values to ensure a leak-free and reliable hydraulic system. Regular inspection of the hydraulic system for leaks and proper torque of fittings is essential for maintaining optimal performance and preventing costly repairs.
The chassis provides the structural foundation for your John Deere 1120, and its components must be securely fastened to ensure safe and reliable operation. The wheel bolts, axle housing bolts, and steering linkage components all have specific torque requirements that must be followed to prevent accidents and maintain proper handling. Loose wheel bolts can lead to wheel separation, while loose steering linkage components can cause loss of control. Always check the torque of chassis components during regular maintenance and tighten fasteners to the recommended values.
In addition to the major structural components, smaller chassis components such as the seat mounting bolts, fender mounting bolts, and hood latch mechanisms also require proper torque. Loose or improperly tightened fasteners on these components can lead to discomfort, damage, or even safety hazards. Regularly inspect these components and tighten fasteners to the specified torque values to ensure a comfortable and safe operating environment. Maintaining the integrity of the chassis components is essential for the overall reliability and longevity of your John Deere 1120 tractor.
This chapter provides detailed parts lists and exploded diagrams for the John Deere 1120 tractor. Accurate parts identification is crucial for efficient maintenance and repair. Using these lists and diagrams, you can quickly locate the correct part number and description for ordering or replacement. Always refer to the diagram first to understand the part's location within the assembly. The following sections break down the tractor into major systems, offering comprehensive information for each component.
This section covers all engine-related components, from the cylinder head to the oil pan. Each diagram illustrates the engine assembly with numbered callouts corresponding to the parts list. The parts list includes the John Deere part number, a detailed description of the part, and any relevant notes or specifications. Pay close attention to serial number breaks, as some parts may vary depending on the tractor's manufacturing date. Proper engine component identification will ensure a successful engine repair or overhaul.
Detailed diagrams are included showing the cooling system components, including the radiator, water pump, and thermostat housing. Each individual hose will be listed as well, along with its location in the cooling system. Special note is made of the coolant type for each engine, and warnings about mixing types. Diagrams also include details about the fuel system components, including the fuel tank, fuel lines, fuel pump, and injectors.
The transmission is a complex system requiring careful attention to detail. The diagrams in this section illustrate the transmission assembly, including gears, shafts, bearings, and seals. The parts list provides the John Deere part number, description, and any relevant notes. Before disassembling the transmission, thoroughly study the diagrams to understand the location and function of each part. Ensure you have the correct tools and equipment for transmission repair. Always observe proper torque specifications during reassembly to prevent damage.
Be especially aware of the different gear ratios available for this tractor. These will be denoted in the parts list next to each individual gear listing. If you are planning any sort of customization, take careful note of the gear ratio of each gear, to be sure that you do not negatively affect the performance of the tractor. If you intend to change a single gear, you must change all of the gears on that shaft. It is not possible to get the tractor to function correctly if this is not done.
This section details the hydraulic system, including the hydraulic pump, control valves, cylinders, and hoses. The diagrams illustrate the hydraulic system layout, making it easier to trace hydraulic lines and identify components. The parts list includes the John Deere part number, description, and pressure ratings where applicable. When working on the hydraulic system, ensure the system is depressurized to prevent injury. Use caution when handling hydraulic fluid, as it can be harmful. Replacing seals and O-rings is crucial to maintaining a leak-free hydraulic system.
Detailed diagrams are provided on how to assemble and dissemble the hydraulic pump. Special note is made of the seal and gasket placement, as improperly placed seals and gaskets are a common cause of problems when reassembling the hydraulic system. Make certain that you are using the correct hydraulic fluid in this system, as the incorrect fluid can cause damage to the seals in the hydraulic cylinders. These can be damaged quickly so it is important to use the correct fluid at all times.
The electrical system section covers the wiring harness, starter, alternator, lights, and gauges. Diagrams illustrate the wiring schematics, making it easier to troubleshoot electrical issues. The parts list includes the John Deere part number, description, and voltage/amperage ratings where applicable. When working on the electrical system, disconnect the battery to prevent short circuits. Use a multimeter to diagnose electrical problems and ensure proper connections. Always replace faulty wiring and components with the correct replacements.
Full wiring diagrams are provided in this section, which will give a full overview of the entire electrical system of the tractor. Every single circuit on the entire machine is captured in this one diagram. Use a multimeter to check continuity of each wire and to verify that your wiring matches the wiring in the diagram. If you are missing something on your machine, use this diagram to aid in your understanding of the system and how it works. Always be certain to use the correct fuse size in this machine to avoid fire.
This section covers the chassis components, including the frame, axles, wheels, and steering system. The diagrams illustrate the chassis assembly, showing the location of each component. The parts list includes the John Deere part number, description, and dimensions where applicable. Inspect the chassis regularly for cracks, damage, or wear. Tighten bolts to the specified torque to ensure proper alignment and stability. Replacing worn or damaged chassis parts is essential for safe operation.
Detailed exploded views of the front axle are included in this section. Particular attention is drawn to the steering components and how to adjust the front end to correct steering issues. Always check the tire pressure for the front tires, as this can cause issues when steering. Always make sure that both tires are at the same pressure, as this will aid in the equal distribution of pressure on the front axle. This will also aid in making sure that the machine steers properly.