Operating and maintaining a CASE IH Farmall 120C tractor requires a thorough understanding of safety procedures. Always prioritize safety to prevent personal injury or damage to equipment. Before beginning any maintenance or repair task, carefully read and understand all safety decals and warnings located on the tractor. Failure to follow these warnings could result in serious injury or death. Never operate the tractor under the influence of alcohol or drugs, and ensure you are physically and mentally fit for the task at hand. Proper training is also crucial; if you are unfamiliar with a specific procedure, seek guidance from a qualified technician before proceeding.
Always disconnect the battery's negative (-) terminal before working on any electrical components. This prevents accidental electrical shocks and damage to sensitive electronic systems. When working under the tractor, use approved jack stands or ramps to support the machine securely. Never rely solely on hydraulic jacks, as they can fail unexpectedly. Wear appropriate personal protective equipment (PPE), including safety glasses, gloves, and ear protection, as needed. Be aware of moving parts, such as the engine fan and belts, and keep hands and clothing clear. Dispose of fluids, filters, and other waste materials in an environmentally responsible manner according to local regulations.
Proper tightening of fasteners is critical for the reliable operation of your Farmall 120C. Torque specifications ensure that components are securely fastened without over-stressing the hardware or the joined parts. Refer to the torque charts provided in this manual for the correct torque values for various fasteners, including bolts, nuts, and screws. These charts are organized by fastener size, thread pitch, and grade, so be sure to identify the correct fastener before applying torque. Always use a calibrated torque wrench to ensure accurate torque application.
When tightening fasteners in a pattern, such as cylinder head bolts or wheel nuts, follow the specified tightening sequence to ensure even distribution of force. This prevents warping and ensures a proper seal. Before tightening, inspect the threads of both the fastener and the receiving hole for damage or debris. Clean or replace damaged fasteners as needed. Lubricate threaded surfaces with the appropriate lubricant, such as anti-seize compound, unless otherwise specified. This helps to prevent seizing and ensures accurate torque readings. After tightening, double-check the torque values to ensure they are within the specified range. Regularly recalibrate your torque wrench to maintain accuracy.
Regular lubrication and maintenance are essential for extending the lifespan and ensuring the optimal performance of your Farmall 120C. Adhering to the recommended maintenance schedule helps prevent premature wear, component failure, and costly repairs. The lubrication and maintenance schedule outlines the tasks that should be performed at specific intervals, measured in operating hours or calendar time. These tasks include changing engine oil and filters, lubricating chassis components, checking fluid levels, inspecting belts and hoses, and servicing the air filter.
Use only the recommended lubricants and fluids specified in this manual. Using incorrect lubricants can damage components and void warranties. Keep accurate records of all maintenance performed, including dates, hours, and parts used. This helps track maintenance history and identify potential issues. Before performing any lubrication or maintenance task, consult the appropriate section of this manual for detailed instructions and safety precautions. Inspect all components thoroughly during maintenance and repair. Replace worn or damaged parts promptly to prevent further damage or safety hazards. Proper maintenance not only ensures reliability but also improves fuel efficiency and reduces environmental impact.
Familiarizing yourself with the major components of your Farmall 120C is crucial for effective troubleshooting and repair. This section provides a visual guide to help you identify the key systems and parts of the tractor. Understanding the location and function of each component will enable you to locate problems more quickly and perform maintenance tasks more efficiently. Refer to the diagrams and illustrations in this section to identify components such as the engine, transmission, axles, hydraulic system, electrical system, and cab.
Pay close attention to the location of filters, fluid reservoirs, and service points. Knowing where these components are located will simplify routine maintenance tasks. Use the component identification guide in conjunction with the parts catalog to identify specific parts and order replacements. As you become more familiar with your tractor, you will be able to diagnose problems more accurately and perform repairs with greater confidence. If you are unsure about the identification or function of a particular component, consult a qualified technician for assistance.
The serial number is a unique identifier for your Farmall 120C tractor. It is essential for ordering parts, accessing warranty information, and identifying the specific configuration of your machine. The serial number is typically stamped on a metal plate or decal that is affixed to the tractor frame. This section provides information on the location of the serial number plate on various models of the Farmall 120C.
Record the serial number in a safe place, such as this service manual or a separate document. This will be helpful if you ever need to order parts or contact your dealer for service. In addition to the main serial number, there may be serial numbers for individual components, such as the engine or transmission. These serial numbers can be useful for identifying specific parts within those components. When ordering parts, provide the complete serial number of your tractor to ensure you receive the correct parts. Do not attempt to remove or alter the serial number plate, as this may void warranties and create legal issues.
The CASE IH Farmall 120C tractor is equipped with a robust and reliable diesel engine designed for optimal performance and durability in demanding agricultural applications. Understanding the engine's key specifications is crucial for effective maintenance, troubleshooting, and repair. This section outlines the vital parameters, including the engine model, displacement, horsepower rating, and compression ratio. These details are essential for correctly identifying parts, setting up diagnostic equipment, and ensuring that all repairs are performed to the manufacturer's specifications. Always refer to the engine's serial number and model code for precise information specific to your tractor.
Specific information, such as bore and stroke measurements, valve timing, and fuel injection pressure, will also be detailed. Knowing the recommended oil type and capacity is paramount for maintaining proper lubrication and preventing engine wear. Furthermore, this section includes torque specifications for critical engine components like cylinder head bolts, connecting rod bolts, and main bearing cap bolts. Adhering to these torque specifications during assembly is critical to ensuring proper sealing and preventing component failure. Neglecting these precise values can lead to leaks, reduced performance, and potentially catastrophic engine damage.
Proper engine disassembly and assembly are fundamental to any repair or overhaul. Before beginning any disassembly, it's crucial to disconnect the battery and drain all fluids, including coolant, engine oil, and fuel. Documenting each step with photographs or detailed notes is highly recommended to ensure correct reassembly. Always work in a clean and well-lit environment to prevent contamination and maintain visibility. Be sure to follow the recommended sequence for removing components, paying attention to any special tools or procedures required.
During assembly, always use new gaskets, seals, and O-rings to ensure a proper seal and prevent leaks. Apply the appropriate lubricants to all moving parts, such as the camshaft, crankshaft, and pistons, to minimize friction and promote longevity. Torque all fasteners to the manufacturer's specified torque values, using a calibrated torque wrench. Verify the proper operation of all components, such as the fuel injectors, water pump, and oil pump, before reinstalling the engine. Remember to prime the lubrication system before starting the engine to prevent damage from dry running.
Engine troubleshooting is a systematic process of identifying the root cause of engine malfunctions. Common symptoms such as hard starting, low power, excessive smoke, and unusual noises can provide valuable clues about the underlying problem. Begin by performing a visual inspection of the engine, checking for leaks, damaged components, and loose connections. Next, use diagnostic tools, such as a compression tester, a multimeter, and a scan tool, to gather data about the engine's performance.
Interpreting the diagnostic data requires a solid understanding of engine operation and troubleshooting techniques. Consult the service manual for specific troubleshooting charts and procedures. Remember to check the basics first, such as fuel supply, air intake, and electrical connections. For complex problems, it may be necessary to consult with a qualified technician. Once the root cause has been identified, take the appropriate corrective action, such as replacing a faulty component or adjusting engine settings. After completing the repair, verify that the problem has been resolved and that the engine is operating correctly.
The cooling system plays a vital role in maintaining the engine's operating temperature and preventing overheating. Regular maintenance of the cooling system is essential for ensuring reliable engine performance and preventing costly repairs. Inspect the coolant level regularly and add coolant as needed, using the recommended coolant type. Check the condition of the radiator hoses and replace any hoses that are cracked, swollen, or deteriorated.
Periodically flush the cooling system to remove deposits and contaminants that can reduce its efficiency. Inspect the radiator fins for damage and clean them as needed. Test the thermostat to ensure that it is opening and closing at the correct temperature. Check the water pump for leaks or unusual noises. If the water pump is faulty, replace it immediately. Regularly inspect the cooling fan and fan clutch, if equipped, to ensure proper operation. Maintaining a clean and efficient cooling system will extend the life of your engine and prevent costly breakdowns.
The fuel system delivers the necessary fuel to the engine for combustion. Regular maintenance of the fuel system is crucial for ensuring proper engine performance and fuel efficiency. Start by regularly inspecting the fuel filter and replacing it as needed. Use the correct filter for your tractor model. Drain any water or sediment from the fuel tank and fuel filter. Inspect the fuel lines and connections for leaks or damage, replacing any faulty components. Proper fuel pressure is critical.
Check the fuel injectors for proper operation and clean or replace them as needed. Inspect the fuel injection pump for leaks or unusual noises. If the fuel injection pump is faulty, it may require professional repair or replacement. Ensure proper calibration of the fuel injection system for optimal performance and fuel economy. Never use fuel additives or cleaning products that are not recommended by the manufacturer. Clean fuel delivers the best and most efficient performance. Routine servicing of the fuel system will help ensure reliable engine operation and optimal fuel efficiency.
The lubrication system provides critical lubrication to all moving parts within the engine, reducing friction and preventing wear. Regular oil changes are essential for maintaining the integrity of the lubrication system. Use the recommended oil type and viscosity for your tractor model and climate conditions. Replace the oil filter with each oil change. A clean filter helps increase the life of your engine.
Inspect the oil lines and connections for leaks or damage, replacing any faulty components. Check the oil pressure regularly to ensure that the lubrication system is functioning correctly. If the oil pressure is low, investigate the cause and take corrective action. Periodically inspect the oil pan for sludge or deposits and clean as needed. Clean oil makes for a happier engine. Regularly maintaining the lubrication system will extend the life of your engine and prevent costly repairs.
Understanding the hydraulic system diagram is paramount to effectively diagnosing and repairing issues on the CASE IH Farmall 120C. The diagram illustrates the flow of hydraulic fluid from the reservoir, through the pump, control valves, cylinders, and back to the reservoir. Familiarize yourself with the location of each component, including pressure relief valves, filters, and test ports. Pay close attention to the color coding used to represent different pressure levels and fluid pathways; this will provide quick visual information when tracing a potential problem. Having a clear mental picture of the system's layout is the first step in identifying where a fault might lie.
The diagram also includes valuable information about the type and size of fittings used throughout the hydraulic system. Knowing this information can save valuable time when replacing hoses or components, ensuring that you use the correct parts. Furthermore, the diagram will show the location of any diagnostic ports and test points that you can use to check the pressure at certain points in the hydraulic system. These test points are vital when you perform pressure testing to isolate problems such as pump failure or valve malfunctions. Make sure that you follow all safety procedures when connecting gauges to these test points.
The hydraulic pump is the heart of the hydraulic system, providing the necessary flow and pressure to operate various implements. Regular maintenance and occasional servicing are crucial for the pump's longevity and performance. Before beginning any pump service, be sure to relieve the pressure in the hydraulic system by turning off the tractor and following the manufacturer’s procedures. Disconnecting the battery is also advisable to prevent accidental starting. Always use clean tools and a clean work area to prevent contamination of the hydraulic fluid and internal components.
When removing the pump, carefully disconnect the hydraulic lines, capping them immediately to prevent fluid leakage and contamination. Inspect the pump's drive coupling for wear or damage; replace it if necessary. Once the pump is removed, thoroughly clean the exterior and inspect the housing for cracks or leaks. A visual inspection of the internal components, such as the gears or pistons, can reveal signs of wear or damage. If significant wear is evident, consider replacing the entire pump with a new or remanufactured unit.
If you choose to rebuild the pump, follow the manufacturer's specifications closely. Use a rebuild kit that includes all the necessary seals, O-rings, and gaskets. When reassembling the pump, lubricate all components with clean hydraulic fluid. Ensure that all bolts are tightened to the specified torque. Prior to reinstalling the pump, flush the hydraulic lines to remove any contaminants. Finally, after installation, bleed the hydraulic system to remove any air. Always perform pressure testing to ensure the system is operating within specification.
The valve bank controls the flow of hydraulic fluid to various implements, allowing the operator to control their movement and function. Malfunctions in the valve bank can lead to issues such as slow response, erratic movement, or complete failure of an implement. Before servicing the valve bank, ensure that the hydraulic system pressure is relieved and the tractor is turned off. Disconnect the hydraulic lines from the valve bank, labeling them clearly to ensure correct reassembly. Clean the exterior of the valve bank thoroughly to prevent dirt and debris from entering the internal components.
When disassembling the valve bank, carefully remove each valve spool, noting its orientation and position. Inspect the spools and valve body for wear, scoring, or corrosion. Minor imperfections can often be cleaned with fine emery cloth, but significant damage may necessitate replacement of the affected components or the entire valve bank. Pay close attention to the condition of the O-rings and seals; replace them whenever the valve bank is disassembled.
Reassemble the valve bank according to the manufacturer's specifications, ensuring that all components are properly lubricated. Torque all bolts to the specified values. After reassembly, test the valve bank on a hydraulic test bench to verify proper operation. If a test bench is unavailable, reinstall the valve bank on the tractor and test each implement function. If problems persist, further troubleshooting may be required.
Hydraulic cylinders convert hydraulic pressure into linear motion, powering various implements such as loaders, backhoes, and mowers. Leaks, slow movement, or complete failure of a cylinder can significantly impact the tractor's productivity. Before servicing a cylinder, ensure that the hydraulic pressure is relieved and the implement is properly supported. Disconnect the hydraulic lines from the cylinder, capping them to prevent fluid leakage. Remove the cylinder from the implement, noting the orientation of the mounting hardware.
To disassemble the cylinder, loosen the gland nut or retaining bolts. Secure the cylinder in a vise or suitable holding fixture. Carefully remove the piston rod assembly from the cylinder barrel. Inspect the piston rod for bends, dents, or corrosion. Examine the cylinder barrel for scoring or damage. Replace any damaged components. Pay close attention to the condition of the piston seals, rod seals, and wiper seals; these are common sources of leaks.
When reassembling the cylinder, lubricate all components with clean hydraulic fluid. Install new seals and O-rings. Torque all bolts to the specified values. After reassembly, test the cylinder for leaks and proper operation. If leaks are detected, further inspection and repair may be necessary. Reinstall the cylinder on the implement, ensuring that all mounting hardware is properly tightened. Always bleed the hydraulic system after installing the cylinder.
Troubleshooting hydraulic system problems requires a systematic approach. Begin by gathering information about the problem, such as when it started, what implements are affected, and any unusual noises or symptoms. Inspect the hydraulic fluid level and condition. Check for leaks in the hydraulic lines, cylinders, and valve bank. Use a pressure gauge to test the hydraulic system pressure at various test points. Compare the readings to the manufacturer's specifications.
If the hydraulic pressure is low, the pump may be faulty. Check the pump's output flow and pressure. If the pump is operating properly, the problem may lie in the valve bank or a cylinder. Isolate the affected circuit and test the components individually. Use a process of elimination to narrow down the source of the problem. Refer to the hydraulic system diagram for assistance.
Common hydraulic system problems include low hydraulic pressure, slow implement movement, erratic implement movement, hydraulic fluid leaks, and overheating. Always refer to the manufacturer's service manual for specific troubleshooting procedures and diagnostic information. Use caution when working on hydraulic systems, as high-pressure fluid can be dangerous.
Using the correct hydraulic oil is crucial for the proper functioning and longevity of the hydraulic system. The CASE IH Farmall 120C requires a specific type of hydraulic oil that meets the manufacturer's specifications. Consult the operator's manual for the recommended oil type and viscosity. Using the wrong hydraulic oil can lead to problems such as reduced performance, increased wear, and premature failure of hydraulic components.
Regularly check the hydraulic oil level and condition. Change the hydraulic oil and filter at the recommended intervals. Contaminated hydraulic oil can damage the hydraulic pump, valve bank, and cylinders. When adding or changing hydraulic oil, use clean containers and funnels to prevent contamination. Always dispose of used hydraulic oil properly.
Consider using a high-quality synthetic hydraulic oil for improved performance and extended service life. Synthetic hydraulic oils offer better resistance to temperature extremes and provide superior lubrication. They can also help to reduce wear and tear on hydraulic components. However, always verify that the synthetic oil is compatible with the hydraulic system components before using it.
Understanding the wiring diagrams is absolutely crucial for diagnosing and repairing electrical problems in your Farmall 120C. These diagrams provide a visual representation of how all the electrical components are connected, allowing you to trace circuits and identify potential faults. Always start your electrical diagnosis by carefully studying the relevant wiring diagram for your specific model and serial number, as there can be variations depending on the year of manufacture and optional features. Familiarize yourself with the symbols used in the diagrams, such as those for resistors, capacitors, diodes, and switches, to accurately interpret the connections. Use a high-quality printed version or a digital copy that you can zoom in on to see the details clearly, especially when tracing complex circuits. Remember to double-check the diagram against the actual wiring on the tractor to ensure they match.
These diagrams generally illustrate the wiring harness routing and connections between major electrical components. They show the location of fuses, relays, and grounds. Proper interpretation of these diagrams will allow you to do continuity testing of the wire harnesses to determine if there are any breaks in the circuits. Many online resources and third-party suppliers offer these diagrams. Some resources are free to use and download while others require a fee.
The starting system is essential for getting your Farmall 120C up and running. It's made up of several key components, including the battery, starter motor, solenoid, and ignition switch. A common problem is a weak battery, which can prevent the starter motor from cranking the engine with sufficient speed. Always check the battery voltage and perform a load test to ensure it's capable of delivering the required current. Another frequent issue is corroded battery terminals, which can impede the flow of electricity. Clean the terminals thoroughly with a wire brush and apply a protective coating to prevent further corrosion. Inspect the starter motor itself for signs of wear or damage, such as worn brushes or a faulty solenoid. If the starter motor clicks but doesn't turn, the solenoid may be the culprit.
When troubleshooting starting problems, begin by verifying that the battery is fully charged and the connections are clean and tight. If the starter motor is turning slowly, inspect the cables and connections for corrosion or damage. If the starter motor is not turning at all, check the solenoid and the ignition switch. To avoid accidental starting, always disconnect the negative battery cable before working on the starting system. When replacing components of the starting system, be sure to use parts designed for your specific make and model to avoid performance issues and compatibility problems.
The charging system is responsible for replenishing the battery's charge while the engine is running and powering the tractor's electrical accessories. Key components include the alternator or generator, voltage regulator, and the battery. A malfunctioning charging system can lead to a dead battery and prevent the tractor from starting. Begin by checking the alternator's output voltage with a multimeter while the engine is running. The voltage should typically be between 13.5 and 14.5 volts. Inspect the drive belt for proper tension and signs of wear or damage. A loose or worn belt can cause the alternator to slip, reducing its output. The voltage regulator controls the alternator's output to prevent overcharging the battery. A faulty voltage regulator can damage the battery and other electrical components.
A visual inspection of the wiring, connectors, and grounds in the charging system can reveal potential issues. Keep in mind that many electrical components will have specific testing parameters that must be met or the component will need to be replaced. Verify that the wires are connected properly and are tightly fitted. Loose wiring can lead to shorts and arcing that could destroy the system. Refer to your owner's manual for specifications and torque values of the hardware to ensure proper and safe function of the electrical system.
Proper functioning of the lighting system is critical for safe operation, especially during low-light conditions. This includes headlights, taillights, turn signals, and work lights. A common issue is burned-out bulbs, which are easy to replace. However, if bulbs are frequently burning out, there may be an underlying electrical problem, such as a voltage surge or a loose connection. Check the fuses for the lighting circuits and replace any that are blown. Inspect the wiring for damage, such as frayed insulation or corroded connectors. Moisture can seep into the light fixtures and cause corrosion, which can lead to dim or non-functioning lights. Clean the connectors and apply dielectric grease to prevent further corrosion. Ensure that the light fixtures are securely mounted and properly grounded.
Consider upgrading to LED lights for increased brightness, longer lifespan, and lower power consumption. LED lights offer a significant improvement over traditional incandescent bulbs and can enhance visibility and safety. When replacing lights, be sure to match the correct voltage and wattage to avoid damaging the electrical system. Always follow the manufacturer's instructions for proper installation and wiring. Periodically test all the lights to ensure they are working properly, especially before operating the tractor in dark or low-visibility conditions.
The instrument panel provides crucial information about the tractor's operating conditions, such as engine temperature, oil pressure, and fuel level. A malfunctioning instrument panel can make it difficult to monitor these parameters and can lead to potential engine damage. Start by checking the fuses for the instrument panel circuits. Inspect the wiring and connectors for damage or corrosion. The gauges themselves may be faulty and require replacement. The sending units, which transmit the information to the gauges, can also fail. Test the sending units to ensure they are providing accurate readings. If the entire instrument panel is not working, there may be a problem with the main power supply or the ground connection.
Many modern instrument panels incorporate digital displays and electronic control units (ECUs). These components can be more complex to troubleshoot and may require specialized diagnostic tools. If you suspect a problem with the ECU, consult a qualified technician who has the necessary equipment and expertise. When working on the instrument panel, be careful not to damage the delicate components. Always disconnect the battery before attempting any repairs. Refer to the service manual for detailed instructions and wiring diagrams.
Troubleshooting electrical problems can be challenging, but with a systematic approach, you can identify and resolve most issues. Start by gathering as much information as possible about the problem. When did it start? What were the circumstances? What have you already tried? Use a multimeter to test voltages, continuity, and resistance in the circuits. Refer to the wiring diagrams to trace circuits and identify potential faults. Check the fuses and relays for proper operation. Inspect the wiring and connectors for damage or corrosion. Look for signs of overheating, such as melted insulation or burned connectors. A visual inspection can often reveal obvious problems. Use a test light to check for power at various points in the circuit.
For intermittent problems, it may be necessary to monitor the circuits over time to catch the fault in action. Use a scan tool to read diagnostic trouble codes (DTCs) from the ECU. These codes can provide valuable clues about the nature and location of the problem. When replacing electrical components, be sure to use high-quality parts that are designed for your specific model. Always disconnect the battery before working on the electrical system. Follow the safety precautions outlined in the service manual. If you are unsure about any aspect of the troubleshooting process, consult a qualified technician.
The CASE IH Farmall 120C braking system is a hydraulically actuated system designed to provide reliable and consistent stopping power. The system relies on a master cylinder, brake lines, calipers, and rotors working in harmony. Understanding each component's role is crucial for proper maintenance and troubleshooting. A typical setup includes two independent brake circuits for redundancy, ensuring that if one circuit fails, the operator still retains a degree of braking ability. Regular inspection and maintenance are essential to ensure the safe and efficient operation of the tractor.
The hydraulic fluid used in the braking system is specially formulated to withstand high temperatures and pressures. Using the correct type of fluid is critical to prevent premature wear and damage to the system components. Always refer to the manufacturer's specifications for the recommended fluid type and change intervals. Contaminated or degraded fluid can lead to reduced braking performance, corrosion, and eventual failure of the system. Therefore, periodic fluid checks and flushes are a vital part of preventative maintenance.
Proper brake pedal adjustment is essential for optimal braking performance and safety. Incorrectly adjusted pedals can lead to uneven braking, reduced stopping power, and premature wear of brake components. The procedure typically involves adjusting the free play in the pedal linkage to ensure the master cylinder is properly activated. Refer to the service manual for specific adjustment procedures and specifications for your model. Make sure both pedals are adjusted evenly to avoid pulling to one side during braking.
Before performing any adjustment, ensure the parking brake is disengaged and the tractor is parked on a level surface. Use the correct tools and follow the recommended steps carefully to avoid damaging the brake system. After making the adjustments, test the brakes to ensure they are functioning correctly and that both wheels brake evenly. If you are unsure about any aspect of the adjustment procedure, consult a qualified technician.
The master cylinder is the heart of the hydraulic braking system, responsible for converting mechanical force from the brake pedal into hydraulic pressure. Over time, the master cylinder can develop leaks or internal wear, leading to reduced braking performance. Servicing the master cylinder typically involves inspecting for leaks, rebuilding with new seals, or replacing the entire unit. Ensure the replacement or rebuild kit is specifically designed for your CASE IH Farmall 120C.
When servicing the master cylinder, it's crucial to maintain cleanliness and prevent contaminants from entering the system. Use clean tools and work in a dust-free environment. Bleeding the brakes after servicing the master cylinder is essential to remove any air from the system. Follow the correct bleeding procedure outlined in the service manual to ensure proper braking performance. Improper bleeding can result in spongy brakes and reduced stopping power.
The brake calipers are responsible for applying pressure to the brake rotors, which in turn slows or stops the wheels. Calipers can experience wear and tear, including worn brake pads, sticking pistons, and damaged seals. Regular inspection of the calipers is essential to ensure they are functioning correctly. If you notice uneven wear on the brake pads, sticking brakes, or fluid leaks, it's time to service the calipers. This may involve replacing the brake pads, rebuilding the caliper with new seals, or replacing the entire caliper assembly.
When replacing brake pads, always use high-quality pads that are designed for your tractor. Clean the caliper thoroughly before installing the new pads. If the caliper piston is sticking, you may need to use a caliper piston tool to retract it. Always wear appropriate safety gear, including eye protection, when working with brake components. After servicing the calipers, bleed the brakes to remove any air from the system and ensure proper braking performance.
Diagnosing braking problems can sometimes be challenging, but a systematic approach can help you pinpoint the issue. Common braking problems include spongy brakes, reduced stopping power, uneven braking, and noisy brakes. Spongy brakes are often caused by air in the hydraulic system, while reduced stopping power can be due to worn brake pads, a faulty master cylinder, or contaminated brake fluid. Uneven braking may be caused by incorrectly adjusted brake pedals, a sticking caliper, or a damaged brake rotor. Noisy brakes can be a sign of worn brake pads, a damaged rotor, or a loose caliper.
Begin by inspecting the brake fluid level and condition. Check for leaks in the brake lines, master cylinder, and calipers. Inspect the brake pads for wear and damage. Operate the brake pedals and observe the movement of the calipers. If you suspect air in the system, bleed the brakes. If the problem persists, consult a qualified technician. Accurate diagnosis and timely repairs can prevent more serious and costly damage to the braking system.
Understanding the layout of your Farmall 120C's steering system is crucial for effective maintenance and repair. The steering system is generally comprised of the steering wheel, steering column, hydraulic pump, hydraulic reservoir, steering control unit, steering cylinders, and the associated hydraulic lines. The steering wheel, through the steering column, connects to the steering control unit, often located near the front axle. This unit is the brain of the operation, interpreting the driver's steering inputs and directing hydraulic fluid to the appropriate steering cylinder(s) to turn the wheels.
The hydraulic pump, powered by the engine, provides the necessary hydraulic pressure for the power steering system. It draws fluid from the hydraulic reservoir and delivers it to the steering control unit under pressure. The reservoir serves as a storage tank for the hydraulic fluid, and often includes a filter to remove contaminants, ensuring smooth and efficient operation of the hydraulic components. Understanding the specific locations of these components on your tractor, aided by a detailed system diagram from your service manual, will significantly simplify troubleshooting and repair procedures.
The steering column is the mechanical link between the operator and the steering system. Over time, wear and tear can develop within the column, leading to play or looseness in the steering wheel. Diagnosing problems in the steering column typically involves checking for excessive play in the steering wheel and inspecting the universal joints and bearings within the column. A loose steering wheel can create difficulty in operating the machinery and make it unsafe.
Servicing the steering column may involve tightening or replacing worn components such as bushings, bearings, or universal joints. Before disassembling the column, be sure to disconnect the battery to prevent accidental activation of any electrical components. When reassembling, pay close attention to the torque specifications for all fasteners to ensure proper function and prevent premature wear. It is crucial to use the correct tools and follow the recommended procedures outlined in the service manual to avoid damaging the column.
The power steering pump is the heart of the hydraulic steering system, providing the necessary pressure to assist the operator in turning the wheels. A failing power steering pump can manifest itself as stiff steering, a whining noise from the pump, or a loss of power steering assist. Regular maintenance, including checking the hydraulic fluid level and inspecting the pump for leaks, is crucial to prolonging the pump's lifespan. Low fluid levels can cause the pump to cavitate, leading to damage and reduced performance.
Servicing the power steering pump typically involves removing the pump from the tractor, disassembling it, inspecting the internal components for wear, and replacing any worn parts such as seals, bearings, or vanes. Before disassembling the pump, be sure to drain the hydraulic fluid and mark the position of all hoses and fittings to ensure proper reassembly. When installing a new or rebuilt pump, it's essential to prime the pump with hydraulic fluid before starting the engine to prevent damage. Refer to the service manual for detailed instructions on pump removal, disassembly, inspection, and reinstallation.
The steering cylinders are responsible for converting hydraulic pressure into the mechanical force that turns the tractor's wheels. Leaks from the steering cylinders are a common issue and can indicate damaged seals or scored cylinder walls. These leaks will not only reduce steering performance but also create environmental hazards. Regular inspection of the steering cylinders for leaks and damage is crucial for maintaining proper steering functionality.
Servicing the steering cylinders involves removing the cylinder from the tractor, disassembling it, inspecting the cylinder bore and piston rod for damage, and replacing any worn or damaged seals. Use caution when disassembling the cylinder, as it may contain residual hydraulic pressure. When installing new seals, be sure to lubricate them with hydraulic fluid to prevent damage during installation. Refer to the service manual for the correct torque specifications for all fasteners and for detailed instructions on cylinder removal, disassembly, inspection, and reinstallation.
Troubleshooting steering problems requires a systematic approach. Start by checking the hydraulic fluid level and inspecting for leaks. Low fluid levels can indicate a leak in the system, while air in the system can cause erratic steering. Next, check the steering linkage for excessive play or binding. Worn or damaged linkage components can impair steering accuracy and responsiveness.
If the hydraulic fluid level is correct and the steering linkage is in good condition, the problem may lie with the power steering pump or the steering control unit. Use a pressure gauge to check the output pressure of the power steering pump. Low pressure can indicate a failing pump. If the pump pressure is within specifications, the steering control unit may be faulty and require further testing or replacement. Always refer to the service manual for detailed troubleshooting procedures and diagnostic tests.
The front axle on your CASE IH Farmall 120C is a critical component for steering and stability. Regular maintenance is key to ensuring optimal performance and longevity. This section details the necessary procedures for maintaining and servicing the front axle, including lubrication points and inspection for wear or damage. Always refer to the lubrication chart in the general maintenance section of this manual for specific grease types and intervals. Ignoring proper lubrication can lead to premature wear of bushings, kingpins, and other critical components, resulting in costly repairs and compromised steering performance.
Before performing any service on the front axle, ensure the tractor is safely supported. Use appropriate jack stands and wheel chocks to prevent accidental movement. Visually inspect the axle housing, steering linkage, and tie rod ends for any signs of cracks, leaks, or excessive play. Check the condition of the axle pivot pin and bushings. Excessive wear in these areas can contribute to steering wander and reduced stability, especially at higher speeds. Replace worn components promptly to maintain safe and predictable handling.
When servicing the front axle, pay close attention to the wheel bearings. Clean and repack them with high-quality bearing grease at the recommended intervals. Improperly lubricated or worn wheel bearings can cause excessive heat, noise, and ultimately, bearing failure. During reassembly, ensure the bearings are properly adjusted according to the specifications outlined in this manual. Over-tightening the bearings can cause premature wear, while under-tightening can lead to excessive play and potential damage to the bearing races. After reassembly, confirm smooth wheel rotation and correct steering geometry.
The rear axle is the backbone of your Farmall 120C's drivetrain, responsible for transmitting power from the transmission to the rear wheels. Proper maintenance is vital to ensure reliable operation and prevent costly downtime. Regularly check the rear axle oil level according to the service schedule outlined in this manual. Using the correct type and quantity of oil is crucial for lubricating the gears and bearings within the axle housing. Low oil levels or contaminated oil can lead to excessive wear and premature failure of internal components.
Inspect the rear axle housing for any signs of leaks or damage. Pay particular attention to the seals around the axle shafts and the differential housing. Leaks should be addressed promptly to prevent oil loss and potential contamination of the brake linings. When replacing seals, ensure the sealing surfaces are clean and free of debris. Use the correct tools and techniques to install the new seals without causing damage. Improperly installed seals can lead to recurring leaks and further maintenance issues.
When servicing the rear axle, carefully inspect the condition of the axle shafts and bearings. Look for signs of wear, pitting, or discoloration. If any damage is detected, replace the affected components immediately. Operating with damaged axle shafts or bearings can lead to catastrophic failure, resulting in significant damage to the axle housing and other drivetrain components. Following the manufacturer's recommended service intervals and using genuine CASE IH replacement parts will help ensure the long-term reliability of your rear axle.
Proper wheel removal and installation are essential for safe and efficient operation. Always use the correct tools and techniques to prevent damage to the wheels, tires, and axle components. Before removing a wheel, ensure the tractor is parked on a level surface and the parking brake is engaged. Loosen the lug nuts slightly before lifting the tractor with a suitable jack. Using a wheel chock is always recommended to prevent accidental movement of the tractor.
When lifting the tractor, ensure the jack is placed on a solid, stable surface. Use appropriate jack stands to support the tractor before removing the wheel completely. Never work under a tractor supported only by a jack. After removing the wheel, inspect the wheel mounting surfaces for any signs of rust, corrosion, or damage. Clean the surfaces thoroughly with a wire brush before reinstalling the wheel. Damage to the mounting surface can be a safety issue and not allow the wheel to tighten properly.
When reinstalling the wheel, align the wheel studs with the corresponding holes in the wheel. Hand-tighten the lug nuts in a star pattern to ensure even distribution of the load. Lower the tractor to the ground and tighten the lug nuts to the specified torque using a torque wrench. Over-tightening the lug nuts can damage the wheel studs, while under-tightening can lead to wheel loosening and potential accidents. Recheck the lug nut torque after a few hours of operation to ensure they remain properly tightened. This is a critical step for safe and reliable operation.
Selecting the correct tires for your Farmall 120C is crucial for maximizing performance, efficiency, and safety. The tire size and type should be matched to the specific application and operating conditions. Refer to the tire placard on the tractor or in the operator's manual for the recommended tire sizes and inflation pressures. Using the wrong tires can negatively impact traction, stability, and fuel consumption. Always follow the manufacturer's recommendations to ensure optimal performance and prevent damage to the tires and drivetrain.
Proper tire inflation is essential for maintaining optimal performance and extending tire life. Regularly check the tire pressure with an accurate gauge. Inflate the tires to the recommended pressure for the specific load and operating conditions. Under-inflated tires can cause excessive wear, increased rolling resistance, and reduced fuel efficiency. Over-inflated tires can result in a harsh ride, reduced traction, and increased risk of tire damage. Check tire pressure often during heavy use.
Inspect the tires regularly for any signs of wear, damage, or cracking. Pay particular attention to the sidewalls and tread area. Replace worn or damaged tires immediately to prevent potential accidents. Consider the type of terrain and application when selecting replacement tires. For example, agricultural tires with aggressive tread patterns are ideal for field work, while industrial tires with a smoother tread pattern are better suited for hard surfaces. The right tire is key to getting the job done right!
Proper wheel alignment is critical for ensuring optimal handling, tire wear, and fuel efficiency. Misaligned wheels can cause excessive tire wear, steering problems, and reduced fuel economy. Regularly check the wheel alignment according to the service schedule outlined in this manual. If you notice any signs of misalignment, such as uneven tire wear or steering pull, have the alignment checked and adjusted by a qualified technician.
The front wheel alignment should be checked and adjusted whenever the front axle is serviced or after any significant impact. The alignment procedure typically involves adjusting the toe-in or toe-out of the front wheels. Toe-in refers to the distance between the front edges of the tires being slightly closer than the rear edges. Incorrect toe-in can cause excessive tire wear and steering instability. Always refer to the manufacturer's specifications for the correct toe-in settings.
When performing wheel alignment adjustments, ensure the tractor is on a level surface and the tires are properly inflated. Use accurate measuring tools to ensure precise adjustments. After making the adjustments, double-check the alignment and test drive the tractor to verify proper handling and steering. Regular wheel alignment checks and adjustments will help ensure optimal performance, tire life, and safety.
The operator's seat in your Farmall 120C is designed for comfort and ergonomic operation, allowing for extended periods of work without excessive strain. Proper adjustment is crucial for optimal control and safety. Familiarize yourself with all adjustment levers and knobs before operating the tractor. These controls typically include fore-aft adjustment, height adjustment, and lumbar support adjustment. Regularly inspect the seat for wear and tear, paying particular attention to the suspension system. A worn seat can contribute to operator fatigue and discomfort.
To adjust the seat, locate the adjustment levers or knobs, usually found beneath or beside the seat cushion. Fore-aft adjustment allows you to position the seat closer to or further from the steering wheel and pedals, ensuring comfortable reach. Height adjustment raises or lowers the seat, providing optimal visibility over the hood. Lumbar support adjustment contours the seat back to your lower back, reducing strain. Before making any adjustments, ensure the tractor is safely parked and the engine is switched off. Failure to do so could result in unexpected tractor movement and potential injury.
For seat service, begin by inspecting the seat cover for tears or damage. Replace the cover if necessary, following the manufacturer's instructions. Check the suspension system for proper operation. If the seat bounces excessively or feels stiff, the suspension may need adjustment or repair. Consult the parts catalog for replacement parts if any components are broken or worn. Regularly lubricate moving parts of the seat mechanism with a light grease to ensure smooth operation. Address any seat issues promptly to maintain operator comfort and safety.
Removing the cab from a Farmall 120C is a significant undertaking, typically required for major repairs or access to components beneath the cab structure. This procedure should only be performed by qualified technicians with the appropriate tools and equipment. Before beginning, disconnect the battery negative cable to prevent electrical shorts and potential damage. Thoroughly inspect the area around the cab, noting the location of all wiring harnesses, hydraulic lines, and other connections that must be disconnected.
Begin by disconnecting all electrical connections running to the cab, carefully labeling each connection to ensure proper reassembly. Disconnect any hydraulic lines and fuel lines, taking precautions to prevent spillage and contamination. Remove any bolts or fasteners securing the cab to the tractor chassis. Use a suitable lifting device, such as a crane or forklift, to carefully lift the cab from the chassis. Ensure the lifting device has sufficient capacity to safely handle the weight of the cab.
Installation is essentially the reverse of the removal process. Carefully lower the cab onto the chassis, aligning the mounting points. Secure the cab with the appropriate bolts and fasteners, tightening them to the specified torque. Reconnect all electrical connections, hydraulic lines, and fuel lines, referring to your labels and diagrams to ensure proper placement. Reconnect the battery negative cable and test all systems to ensure they are functioning correctly. Verify that all controls and instruments within the cab are operating as intended before returning the tractor to service.
The air conditioning (A/C) system in your Farmall 120C provides essential cooling during hot weather, enhancing operator comfort and productivity. Regular maintenance is crucial for ensuring optimal A/C performance. Check the refrigerant level periodically using a manifold gauge set. Low refrigerant levels can indicate leaks in the system, which should be addressed promptly. Inspect the compressor belt for wear and tear, and replace it if necessary. A worn belt can slip, reducing compressor efficiency and cooling capacity.
Clean the condenser coils regularly to remove dirt and debris that can restrict airflow. Use a soft brush or compressed air to clean the coils gently. Inspect the evaporator drain tube for clogs, ensuring proper drainage of condensation. A clogged drain tube can lead to water accumulation and unpleasant odors inside the cab. Check the A/C system for leaks using a refrigerant leak detector. Address any leaks promptly to prevent refrigerant loss and environmental damage.
If the A/C system is not cooling effectively, it may be necessary to evacuate and recharge the system. This procedure requires specialized equipment and training. Consult a qualified A/C technician for assistance. When recharging the system, use the correct type and amount of refrigerant specified by the manufacturer. Overcharging or undercharging the system can damage the compressor and reduce cooling performance.
The heater system in your Farmall 120C provides warmth during cold weather, ensuring operator comfort and preventing frost buildup on the windows. Check the coolant level regularly, as low coolant levels can affect heater performance. Inspect the heater hoses for leaks or damage, and replace them if necessary. A leaking hose can cause coolant loss and reduced heating capacity. Verify that the heater control valve is functioning properly, allowing coolant to flow to the heater core.
Inspect the heater core for leaks or blockages. A leaking heater core can cause a coolant smell inside the cab, and a blocked heater core can reduce heating performance. Check the blower motor for proper operation. The blower motor circulates air through the heater core, distributing warmth throughout the cab. A faulty blower motor can result in reduced airflow and insufficient heating. Ensure the air intake vents are clear of obstructions, allowing for proper airflow into the heater system.
If the heater system is not functioning correctly, it may be necessary to flush the heater core to remove any accumulated debris. This procedure involves disconnecting the heater hoses and circulating a cleaning solution through the heater core. Replace the heater core if it is severely corroded or damaged. Consult the service manual for detailed instructions on heater system troubleshooting and repair. Always use genuine or equivalent replacement parts to ensure optimal performance and longevity.
Proper adjustment of the control levers in your Farmall 120C is essential for precise operation and operator comfort. The control levers include the gear shift lever, hydraulic control levers, and throttle lever. Ensure that each lever moves smoothly and without excessive play. Adjust the levers as needed to provide comfortable reach and effortless operation. A properly adjusted control lever can significantly reduce operator fatigue and improve overall efficiency.
Check the linkage connecting the control levers to their respective components. Worn or loose linkages can result in imprecise control and delayed response. Lubricate the linkage points regularly with a light oil or grease to ensure smooth operation. Inspect the pivot points and bushings for wear and tear, and replace them if necessary. A worn pivot point or bushing can contribute to excessive play and reduced control precision.
Refer to the service manual for specific adjustment procedures for each control lever. Follow the instructions carefully to ensure proper adjustment. Improper adjustment can lead to damage to the transmission, hydraulic system, or engine. After making any adjustments, test the operation of the affected system to ensure it is functioning correctly. If you are unsure about any aspect of control lever adjustment, consult a qualified service technician for assistance.
The loader is a vital attachment for many Farmall 120C owners, increasing the tractor's versatility and utility. Regular service is crucial to ensure its safe and efficient operation. Before performing any maintenance, be sure the loader is lowered to the ground, or securely supported with appropriate stands rated for the loader's weight. Always disengage the tractor's parking brake and remove the ignition key to prevent accidental movement. Neglecting these safety precautions can lead to serious injury or equipment damage.
Begin by inspecting all hydraulic hoses and fittings for leaks, cracks, or wear. Leaks should be addressed immediately, as they not only waste hydraulic fluid but can also create unsafe working conditions. Check the hydraulic fluid level in the reservoir and top off if necessary, using the correct type of fluid specified in the operator's manual. A low fluid level can cause cavitation and damage to the hydraulic pump and loader cylinders.
Next, lubricate all grease fittings on the loader arms, pivots, and cylinders. Use a high-quality grease specifically designed for heavy equipment. Proper lubrication reduces friction and wear, extending the life of the loader components. Pay close attention to any areas that exhibit signs of excessive wear or binding. Overlooking lubrication points can lead to premature failure of critical loader parts, resulting in costly repairs and downtime.
Inspect the loader bucket or other attachments for damage such as cracks, bends, or broken welds. Repair any damage immediately to prevent further deterioration and ensure the attachment's structural integrity. Check the cutting edge of the bucket for wear and replace it if necessary. A worn cutting edge reduces the loader's efficiency and can make it difficult to properly load and unload materials. Always consult the manufacturer's recommendations for specific maintenance procedures and replacement parts.
The three-point hitch is another fundamental attachment that allows the Farmall 120C to utilize a wide range of implements. Proper maintenance of the three-point hitch is essential for accurate implement control and efficient operation. Before commencing any service work, ensure that the implement is safely removed from the hitch and the tractor is parked on a level surface. Engage the parking brake and shut off the engine to prevent any accidental movement during the service procedure.
Begin by inspecting the lift arms, link arms, and stabilizer bars for signs of wear, bending, or damage. Worn or damaged components can affect the implement's stability and accuracy, potentially leading to uneven field work or even equipment failure. Check the pivot points and ball joints for excessive play or looseness. Replace any worn parts immediately to maintain proper hitch geometry and ensure smooth implement operation. Use only genuine CASE IH replacement parts to guarantee compatibility and performance.
Lubricate all grease fittings on the three-point hitch components, paying particular attention to the lift arm pivots and stabilizer bar connections. Proper lubrication minimizes friction and wear, extending the lifespan of the hitch components and preventing binding. Check the hitch control linkage for smooth and responsive operation. Adjust the linkage as needed to ensure precise implement control and accurate positioning. A properly adjusted three-point hitch is crucial for achieving optimal performance with various implements.
Inspect the hydraulic cylinder that controls the lift arms for leaks or damage. A leaking cylinder can cause the implement to drift downward, affecting the quality of work. Check the hydraulic hoses and fittings for signs of wear or leaks. Replace any damaged hoses or fittings immediately to prevent further fluid loss and maintain proper hydraulic pressure. Regularly cleaning the three-point hitch components and applying a protective coating can help prevent corrosion and extend their lifespan.
The Power Take-Off (PTO) is a critical component that transmits power from the tractor engine to implements. Regular maintenance of the PTO is paramount for safe and reliable operation. Before performing any service on the PTO, disengage it completely and shut off the engine. Engage the parking brake and remove the ignition key to prevent accidental engagement. Failure to follow these safety precautions can result in serious injury or damage to the equipment.
Inspect the PTO shaft for any signs of wear, bending, or damage. A damaged PTO shaft can vibrate excessively, causing damage to the implement and potentially leading to a dangerous situation. Check the universal joints for play or looseness. Replace any worn or damaged components immediately to ensure smooth and reliable power transmission. Use only genuine CASE IH replacement parts to guarantee proper fit and performance.
Lubricate the PTO shaft splines regularly with a high-quality grease specifically designed for PTO applications. Proper lubrication prevents wear and corrosion, ensuring smooth engagement and disengagement. Check the PTO shield for damage or missing parts. The PTO shield is a critical safety device that protects operators from accidental contact with the rotating shaft. Replace any damaged or missing shield components immediately.
Verify the PTO engagement and disengagement mechanism is functioning properly. The PTO should engage smoothly and disengage completely without any hesitation or binding. Adjust the linkage as needed to ensure proper operation. Periodically inspect the PTO brake to ensure it effectively stops the PTO shaft when disengaged. A malfunctioning PTO brake can be a safety hazard. Always consult the operator's manual for specific maintenance procedures and safety recommendations related to the PTO.
If your Farmall 120C is equipped with a mower deck, maintaining it properly is crucial for achieving a clean and even cut. Regular service extends the life of the deck and ensures its safe operation. Before starting any maintenance, disconnect the PTO and ensure the engine is off. Engage the parking brake and remove the ignition key. Always wear appropriate safety gear, including gloves and eye protection, when working on the mower deck.
Begin by inspecting the mower blades for sharpness, balance, and damage. Dull or damaged blades can tear the grass, resulting in an uneven cut and potentially damaging the turf. Sharpen or replace the blades as needed, following the manufacturer's recommendations for correct blade angle and balance. A balanced blade ensures smooth operation and reduces vibration. Use a blade balancer to verify the blade's balance after sharpening.
Check the mower deck spindles for looseness or damage. Worn spindle bearings can cause excessive vibration and premature failure of the spindle assembly. Lubricate the spindle bearings according to the manufacturer's recommendations. Inspect the belts for cracks, wear, or fraying. Replace any worn belts immediately to prevent slippage and ensure proper power transmission. A slipping belt reduces the cutting efficiency of the mower deck.
Inspect the mower deck housing for rust, damage, or cracks. Repair any damage to prevent further deterioration. Clean the underside of the mower deck regularly to remove accumulated grass clippings and debris. Excessive buildup can reduce airflow and affect the cutting performance. Ensure all safety shields and guards are in place and in good condition. These shields protect the operator from flying debris and accidental contact with the rotating blades. Refer to the mower deck's operator's manual for detailed maintenance instructions and safety guidelines.
Modern CASE IH Farmall 120C tractors utilize a sophisticated onboard diagnostic system. This system continuously monitors various engine and hydraulic parameters, logging diagnostic trouble codes (DTCs) when anomalies are detected. Understanding these codes is crucial for efficient and accurate troubleshooting. These codes are your first clue in understanding what is wrong with the machine. Always record any codes you find before you attempt any repairs to the system. Make sure to cross reference any codes you find with your service manual for further assistance.
Accessing the diagnostic codes typically involves using the tractor's display panel, following the menu navigation outlined in the operator's manual. The display will show the code number, and sometimes a brief description of the fault. Refer to the detailed diagnostic code list in Appendix A of this manual for a comprehensive explanation of each code. Be sure to consult Appendix A for a detailed explanation of what each code means, and what system it is referring to.
When multiple codes are present, address the most critical or frequently occurring code first. Often, resolving one underlying issue can clear other related codes. This is important because a single point of failure in one system can often trigger codes in another. Clearing codes without identifying the root cause will only result in them reappearing. Remember that diagnostic codes are not always a definitive diagnosis; they are merely indicators that further investigation is required. Diagnostic codes are an aide to help guide you, never the final answer to your issues.
Troubleshooting charts provide a structured approach to diagnosing common problems encountered with the Farmall 120C. These charts guide you through a series of logical steps, asking questions and suggesting tests to narrow down the potential causes of a symptom. Start by identifying the specific symptom the tractor is exhibiting, such as "Engine will not start," "Hydraulic system is slow," or "Transmission slips." Once you have identified the symptom, you can look at the troubleshooting charts to help identify the cause.
Each chart outlines a series of potential causes, along with corresponding inspection and testing procedures. Carefully follow the steps outlined in the chart, using the appropriate tools and equipment. For example, a chart for "Engine will not start" might direct you to check the fuel supply, battery voltage, and starter motor functionality. Ensure you consult the relevant sections of this manual for detailed instructions on performing these tests. These charts often have multiple potential solutions, and it is important to exhaust all possible solutions before moving on to the next one.
If the troubleshooting chart leads you to a specific component, proceed to the "Component Testing Procedures" section for detailed instructions on how to test that component. Remember to document your findings as you progress through the chart. This will help you keep track of what you have already checked and avoid repeating tests. Before you start any system repairs, make sure to take pictures and videos for reference in reassembling them.
This section provides detailed procedures for testing individual components of the Farmall 120C. These procedures typically involve using a multimeter, pressure gauge, or other specialized tools to measure electrical signals, pressures, or other parameters. Before testing any component, disconnect the battery ground cable to prevent accidental electrical shock or damage to the tractor's electronics. It is also important to visually inspect the component for any signs of physical damage, such as cracks, leaks, or corrosion.
Each component testing procedure will specify the correct test points, measurement values, and acceptable tolerances. For example, testing a fuel injector might involve measuring its resistance and observing its spray pattern. Testing a hydraulic pump might involve measuring its output pressure at various engine speeds. Compare your measurements to the specifications listed in the component testing procedure. If the measurements fall outside the acceptable range, the component is likely faulty and needs to be replaced or repaired.
When testing electrical components, be sure to use a high-quality multimeter and ensure that the test leads are properly connected. When testing hydraulic components, take precautions to avoid spills and contamination. Always dispose of used fluids properly. It is critical to make sure you are wearing the proper safety gear, such as safety glasses and gloves, when you are working on your tractor. Always follow the directions as described, if unsure contact a certified technician for assistance.
Maintaining your CASE IH Farmall 120C tractor efficiently and effectively often requires the use of specialized tools designed for specific tasks. These tools are engineered to provide the necessary leverage, precision, or access needed to work on intricate components. Attempting to use generic tools can not only damage parts but also increase the risk of injury. Refer to the official CASE IH parts catalog or service information system to identify the correct part number and specifications for each special tool. Investing in these tools ensures you can perform repairs and maintenance according to factory standards, prolonging the lifespan of your tractor.
Before undertaking any major repair, carefully review the service procedure outlined in this manual and determine if any special tools are required. Many authorized CASE IH dealerships offer special tools for rent, providing a cost-effective solution for occasional tasks. When using specialized tools, always adhere to the manufacturer's instructions and safety guidelines. Neglecting these precautions can lead to improper tool usage, component damage, or personal injury. Regular inspection and maintenance of special tools are also crucial to ensure their continued functionality and reliability.
Accurate measurement and conversion are vital for proper diagnosis, repair, and maintenance of the CASE IH Farmall 120C. This section provides comprehensive conversion charts to help you navigate between various units of measurement commonly encountered in tractor mechanics. This includes conversions for torque (Newton-meters to foot-pounds), pressure (Pascals to PSI), volume (liters to gallons), and temperature (Celsius to Fahrenheit). Having quick access to these charts minimizes errors and ensures that you're using the correct specifications for tightening bolts, checking fluid levels, and assessing engine performance.
Keep in mind that precise conversions are essential for accurate settings and adjustments. When using these charts, always double-check your values to prevent mistakes. Remember, incorrect torque settings, for example, can result in loose bolts, damaged components, or even catastrophic failures. It's also advisable to consult the relevant sections of this manual for any specific unit requirements for individual procedures. Regularly updated conversion charts can be found online through reputable engineering resources.
The parts list is an indispensable resource for accurately identifying and ordering replacement parts for your CASE IH Farmall 120C. This list contains detailed illustrations and part numbers for every component of the tractor, from engine internals to hydraulic fittings to body panels. Using the correct part number is crucial to ensure that you receive the exact replacement part required, minimizing delays and preventing compatibility issues. The parts list is usually organized by system or assembly, making it easy to locate the specific part you need.
When ordering parts, always provide the complete part number and a brief description of the component to your local CASE IH dealer. This helps them confirm the correct part and avoid any confusion. Before installing a new part, visually inspect it to ensure it matches the old one in terms of size, shape, and function. Refer to the appropriate section of this service manual for instructions on how to install the new part correctly. It is recommended to keep an updated copy of the parts list on hand for quick reference.