Working on heavy machinery like the John Deere 855 compact utility tractor requires a significant understanding of safety procedures. Failure to follow these procedures can lead to serious injury or even death. Before you begin any repair or maintenance procedure, thoroughly review all safety warnings and instructions provided in this manual and any supplementary materials that came with your tractor. Always wear appropriate personal protective equipment (PPE), including safety glasses, gloves, and sturdy work boots. Remember to disconnect the battery before working on any electrical components to prevent accidental shocks or short circuits. A clear understanding of these precautions is paramount to a safe and successful repair experience.
This service manual is intended to be a comprehensive guide for qualified technicians performing maintenance, repairs, and overhauls on the John Deere 855 tractor. While we strive to provide accurate and up-to-date information, the complexity of these machines requires a certain level of mechanical aptitude and experience. This manual assumes that the user has a basic understanding of internal combustion engines, hydraulic systems, and electrical circuitry. It is highly recommended that individuals without prior experience seek guidance from a qualified mechanic before attempting any major repairs. This will ensure the job is done safely and correctly, minimizing the risk of damage to the tractor or injury to the operator.
Proper torque is critical for ensuring the integrity and longevity of your John Deere 855. Over-tightening fasteners can strip threads or damage components, while under-tightening can lead to leaks, loosening, and eventual failure. This section of the manual provides detailed torque specifications for various fasteners throughout the tractor. Always use a calibrated torque wrench and refer to the specific torque value for the fastener size and type being used. Regularly check your torque wrench for accuracy, and replace it if it's out of calibration. Maintaining accurate torque will help you reassemble parts properly and maintain the integrity of the tractor.
Understanding fastener types is equally crucial. The John Deere 855 utilizes a variety of bolts, nuts, screws, and other fasteners, each with specific properties and purposes. Identifying the correct fastener size, thread pitch, and material grade is essential for ensuring a proper fit and optimal performance. Replacing a fastener with an incorrect type can compromise the structural integrity of the assembly. If you're unsure about a specific fastener, consult the parts catalog or a knowledgeable parts specialist for assistance. Using the right parts helps you avoid potentially dangerous situations down the road.
Having the right tools and equipment is essential for performing maintenance and repairs on the John Deere 855 efficiently and effectively. Attempting to use makeshift tools or the wrong equipment can lead to damage to the tractor or injury to yourself. This section provides a comprehensive list of the tools and equipment commonly required for servicing the John Deere 855, including wrenches, sockets, screwdrivers, pliers, measuring tools, and specialized equipment. Remember to keep all tools in good working condition and properly maintained. A well-equipped workspace can greatly improve the quality of your work and minimize frustration.
Beyond basic hand tools, certain repairs may require specialized equipment such as a hydraulic jack, stands, an engine hoist, or diagnostic tools. These tools are designed for specific tasks and can significantly simplify the repair process. Investing in high-quality tools will pay off in the long run by improving the speed and accuracy of your work. If you are unsure about the proper use of any tool, consult the manufacturer's instructions or seek guidance from a qualified mechanic. Using the correct tools and knowing how to use them will help you avoid damaging the equipment and potentially hurting yourself.
The John Deere 855's engine is a critical component that requires regular maintenance and occasional repair to ensure optimal performance and longevity. Understanding the various systems that comprise the engine, such as the fuel, cooling, lubrication, and air intake systems, is crucial for effective troubleshooting and servicing. This chapter will guide you through the essential procedures for maintaining and repairing these systems, enabling you to keep your 855 running smoothly for years to come. It is important to always consult the manufacturer's specifications and use appropriate safety precautions when working on any engine component. Remember to disconnect the battery before commencing any repair work to prevent accidental electrical shocks.
Removing the engine from the John Deere 855 is a significant undertaking typically reserved for major repairs or complete overhauls. Before beginning, ensure you have adequate space and the necessary equipment, including an engine hoist, support stands, and the proper tools. Carefully disconnect all electrical connections, fuel lines, coolant hoses, and mechanical linkages. Thoroughly labeling these connections before disconnection is essential for proper reassembly. Drain all fluids from the engine, including oil, coolant, and fuel, to prevent spills and contamination during the removal process. Proceed slowly and methodically, double-checking that all attachments have been detached before lifting the engine from the frame.
The installation of the engine is essentially the reverse of the removal process, but with added attention to detail. Before lowering the engine into place, inspect the engine mounts for wear or damage and replace them if necessary. Ensure that all mounting surfaces are clean and free from debris. Carefully align the engine with the frame and secure it using the correct bolts and torque specifications. Reconnect all previously disconnected components, referring to your labels and the service manual for correct placement and routing. Refill the engine with the appropriate fluids, checking for leaks as you go. Finally, thoroughly inspect all connections and adjustments before starting the engine.
The cylinder head is a vital component of the engine, housing the valves, combustion chambers, and often the fuel injectors. Over time, carbon deposits, valve wear, and gasket failures can compromise the cylinder head's performance. If you notice symptoms such as decreased power, excessive oil consumption, or coolant leaks, a cylinder head inspection is warranted. Begin by removing the cylinder head from the engine, following the manufacturer's instructions and taking care to protect the gasket surfaces. Once removed, thoroughly clean the cylinder head to remove all traces of carbon and oil.
Carefully inspect the valve seats, valve guides, and valve faces for wear or damage. If necessary, these components can be reconditioned or replaced to restore proper valve sealing. Inspect the cylinder head for cracks or warping, using a straightedge and feeler gauge to check for flatness. If significant warping is present, the cylinder head may need to be resurfaced by a qualified machine shop. When reassembling the cylinder head, use new gaskets and torque the cylinder head bolts to the manufacturer's specifications. Proper torqueing is crucial to ensure a leak-free seal and prevent damage to the cylinder head.
The fuel system is responsible for delivering the correct amount of fuel to the engine at the right time, enabling proper combustion. Fuel system problems can manifest in various ways, including hard starting, rough idling, poor acceleration, and excessive fuel consumption. Diagnosing fuel system issues often requires a systematic approach, starting with a visual inspection of the fuel lines, fuel filter, and fuel pump. Check for leaks, cracks, or clogs that could restrict fuel flow. Use a fuel pressure gauge to verify that the fuel pump is delivering the correct pressure to the injectors.
If the fuel filter is clogged, replace it with a new one. If the fuel pump is faulty, it may need to be replaced or rebuilt. Inspect the fuel injectors for proper spray patterns and flow rates. Clogged or malfunctioning injectors can significantly impact engine performance. Consult the service manual for detailed troubleshooting procedures and component specifications. When working on the fuel system, always exercise caution and avoid open flames, as fuel is highly flammable.
The cooling system is essential for maintaining the engine at its optimal operating temperature, preventing overheating and damage. Regular cooling system maintenance includes checking the coolant level, inspecting the radiator and hoses for leaks, and testing the coolant for proper freeze protection and corrosion inhibitors. Low coolant levels can lead to overheating, while leaking hoses or a clogged radiator can reduce the cooling system's efficiency. Coolant should be replaced periodically to prevent corrosion and maintain its protective properties.
Visually inspect the radiator for damage, such as bent fins or leaks. If necessary, clean the radiator fins with a soft brush to remove debris. Check the coolant hoses for cracks, swelling, or signs of deterioration. Replace any damaged hoses. Use a coolant tester to check the coolant's freeze protection and corrosion inhibitor levels. If necessary, add coolant or flush and refill the cooling system. Always use the correct type of coolant specified by the manufacturer.
The lubrication system is responsible for providing oil to all moving parts of the engine, reducing friction and preventing wear. Regular oil changes are crucial for maintaining the lubrication system's effectiveness. Check the oil level regularly and add oil as needed. Inspect the oil filter for clogs or damage and replace it at the recommended intervals. Inspect the oil lines and oil pump for leaks or damage. Low oil pressure can indicate a serious problem with the lubrication system and should be addressed immediately.
When changing the oil, use the correct type and viscosity of oil specified by the manufacturer. Ensure that the oil filter is properly installed and tightened. Check for oil leaks after changing the oil. Monitor the oil pressure gauge regularly to ensure that the lubrication system is functioning properly. Low oil pressure can indicate a worn oil pump, clogged oil filter, or other serious problems. A qualified mechanic should address those issues.
The air intake system provides clean air to the engine for combustion. A dirty air filter can restrict air flow, reducing engine power and fuel efficiency. Regularly inspect the air filter and clean or replace it as needed. Check the air intake hoses and connections for leaks or damage. Leaks in the air intake system can allow unfiltered air to enter the engine, causing damage.
Clean the air filter by tapping it lightly or using compressed air. Replace the air filter if it is heavily soiled or damaged. Inspect the air intake hoses for cracks or leaks. Replace any damaged hoses. Ensure that all air intake connections are tight and secure. A clean and properly functioning air intake system is essential for optimal engine performance and longevity.
Understanding the electrical system of your John Deere 855 is crucial for effective troubleshooting and repair. This section provides detailed wiring diagrams that illustrate the connections between various electrical components. These diagrams are indispensable tools for tracing circuits, identifying shorts or open circuits, and ensuring that components are properly wired. Furthermore, we provide precise locations of key electrical components within the tractor's chassis, including the starter motor, alternator, voltage regulator, fuses, relays, and control modules. Knowing the physical location of these components will save you valuable time and effort when performing diagnostics or replacements. Refer to these diagrams frequently and always disconnect the battery ground cable before commencing any electrical work to prevent accidental shorts or electrical shocks.
Accurate interpretation of wiring diagrams is essential. Pay close attention to the symbols used to represent different components, wire colors, and circuit numbers. The diagrams are organized to represent the electrical system in a clear and logical manner, making it easier to trace circuits and identify potential faults. In addition to the diagrams, component location diagrams are provided. These diagrams pinpoint the exact location of each major electrical component within the tractor's frame and body. This knowledge is invaluable when diagnosing issues or replacing parts, as it reduces the time spent searching for the correct component. When navigating the electrical system, remember to prioritize safety by disconnecting the battery before undertaking any work, and always refer to the appropriate wiring diagrams and component locations for accurate guidance.
A malfunctioning starting system can bring your work to a standstill. This section provides a step-by-step guide to troubleshooting common starting system problems in your John Deere 855. Begin by visually inspecting the battery cables for corrosion and ensuring they are securely connected to the battery terminals and the starter motor. Use a multimeter to test the battery voltage and ensure it is within the acceptable range. If the battery is good, proceed to check the starter solenoid for proper operation. A faulty solenoid can prevent the starter motor from engaging. Use a test light or multimeter to confirm that the solenoid is receiving power when the key is turned to the start position.
If the solenoid is functioning correctly but the starter motor does not engage, the starter motor itself may be faulty. Before replacing the starter motor, carefully inspect the wiring harness and connections leading to the starter. Look for damaged wires, loose connections, or corrosion. Use a multimeter to check for voltage at the starter motor terminals when the key is in the start position. If voltage is present but the starter motor does not turn, the starter motor likely needs to be replaced. Always disconnect the battery before removing or replacing the starter motor to prevent accidental shorts or electrical hazards. Following these troubleshooting steps will help you quickly identify and resolve starting system problems, getting your John Deere 855 back in operation.
A properly functioning charging system is vital for keeping your John Deere 855's battery charged and powering its electrical components. If you suspect a charging system problem, begin by visually inspecting the alternator belt for wear or damage and ensuring it is properly tensioned. A loose or damaged belt can prevent the alternator from charging the battery effectively. Use a multimeter to measure the battery voltage with the engine running. The voltage should typically be between 13.5 and 14.5 volts when the alternator is charging correctly. If the voltage is below this range, the alternator may not be producing sufficient output.
If the alternator output is low, check the wiring harness and connections leading to the alternator and voltage regulator. Look for damaged wires, loose connections, or corrosion. Use a multimeter to check the alternator output voltage directly at the alternator terminals. If the alternator is producing sufficient voltage at the terminals but the battery voltage remains low, the voltage regulator may be faulty. The voltage regulator controls the alternator output and prevents overcharging the battery. A faulty voltage regulator can cause the battery to either undercharge or overcharge. Replacing a faulty voltage regulator is often necessary to restore proper charging system function. Always disconnect the battery before performing any work on the charging system to prevent accidental shorts or electrical damage.
Proper lighting is essential for safe operation of your John Deere 855, especially during low-light conditions. This section provides guidance on repairing common lighting system problems. Start by visually inspecting all lights for burned-out bulbs. Replace any bulbs that are damaged or non-functional. Check the light sockets for corrosion or damage, as this can prevent proper electrical contact. Use a test light to confirm that the light sockets are receiving power when the corresponding switch is activated. If power is not reaching the socket, there may be a problem with the wiring, switch, or fuse.
Inspect the wiring harness and connections leading to the lights for damage, loose connections, or corrosion. Use a test light or multimeter to trace the circuit and identify any breaks or shorts in the wiring. Check the fuses associated with the lighting system. A blown fuse can indicate a short circuit or overload in the system. Replace any blown fuses with fuses of the correct amperage rating. If the fuses continue to blow, there is likely a short circuit that needs to be located and repaired. Proper lighting is crucial for safety, so addressing any lighting system issues promptly is essential. By following these troubleshooting steps, you can effectively diagnose and repair common lighting system problems on your John Deere 855.
The instrument panel and controls provide essential information about your John Deere 855's operating conditions and allow you to control various functions. If you experience problems with the instrument panel or controls, begin by visually inspecting the panel for any obvious damage or loose connections. Check the wiring harness and connectors leading to the instrument panel for damage, corrosion, or loose connections. Use a multimeter to check for power and ground at the instrument panel. Ensure that the panel is receiving the necessary voltage to operate correctly.
If specific gauges or indicators are not functioning, check the sending units associated with those gauges. For example, if the temperature gauge is not working, check the temperature sending unit for proper operation. Use a multimeter to test the sending unit resistance and compare it to the manufacturer's specifications. If the sending unit is faulty, it will need to be replaced. Inspect the control levers and switches for proper operation. Ensure that the levers move freely and that the switches engage and disengage correctly. Lubricate any stiff levers or switches with a suitable lubricant. If a switch is faulty, it will need to be replaced. A properly functioning instrument panel and controls are essential for monitoring your John Deere 855's performance and ensuring safe operation.
The transmission on your John Deere 855 is a critical component responsible for transferring power from the engine to the wheels. Regular servicing is paramount to ensure smooth operation and longevity. This includes checking the transmission oil level and condition, as well as inspecting for any leaks around the seals and gaskets. A neglected transmission can lead to slipping gears, difficulty shifting, or even complete failure, resulting in costly repairs. Furthermore, pay close attention to any unusual noises emanating from the transmission area during operation, as this could be an early warning sign of impending issues.
Overhauling the transmission is a more involved process typically required when significant wear and tear have occurred. This usually involves disassembling the transmission, inspecting each individual component for damage or wear, and replacing any necessary parts. Common replacement items include bearings, gears, seals, and clutches. It's crucial to use genuine John Deere parts during an overhaul to ensure proper fit and performance. The entire process should be meticulously documented and performed in a clean environment to prevent contamination. Following reassembly, proper lubrication and adjustment are essential for optimal operation.
When diagnosing transmission problems, several factors should be considered. Begin by checking the transmission fluid level and condition. Low fluid levels can cause slipping and overheating, while contaminated fluid can damage internal components. Next, inspect the shift linkage for proper adjustment and ensure that the clutch is engaging and disengaging smoothly. If these checks don't reveal the source of the problem, it may be necessary to remove and disassemble the transmission for a more thorough inspection. Remember to consult the exploded diagrams and torque specifications in this manual during reassembly.
The differential plays a vital role in allowing the wheels on your John Deere 855 to rotate at different speeds during turns. This prevents tire slippage and ensures smooth handling. Regular maintenance includes checking the differential oil level and condition and inspecting for leaks around the seals. A low oil level or contaminated oil can lead to excessive wear on the internal gears and bearings, resulting in noise and eventual failure. Therefore, ensure proper lubrication is maintained according to the recommended service intervals.
Repairing the differential often involves disassembling the unit and inspecting the gears, bearings, and axle shafts for wear or damage. Common problems include chipped or broken gear teeth, worn bearings, and damaged seals. If any of these issues are present, the affected parts should be replaced with genuine John Deere components. When reassembling the differential, it is crucial to properly adjust the pinion bearing preload and the gear backlash to ensure proper meshing and prevent premature wear. Consult the service manual for specific torque specifications and adjustment procedures.
Specialized tools are often required for differential repair, such as a dial indicator for measuring backlash and a torque wrench for tightening fasteners to the correct specifications. Always follow the manufacturer's instructions carefully to avoid damaging the components. After reassembly, check the differential oil level and add the correct type of lubricant as specified in the service manual. A test drive can then be performed to ensure proper operation and to identify any remaining issues. Listen for unusual noises and monitor for any signs of overheating.
The final drive is the last stage of power transmission before the wheels, providing the necessary torque multiplication for heavy-duty tasks. It is a robust system, but requires periodic maintenance to ensure long-term reliability. This involves checking the final drive oil level and condition, as well as inspecting for leaks around the seals and bearings. Insufficient lubrication or contaminated oil can lead to excessive wear on the internal gears and bearings, causing noise and eventually failure. Regular inspection and timely maintenance are essential to prevent costly repairs.
Maintaining the final drive also includes inspecting the axle shafts and bearings for any signs of wear or damage. Worn or damaged components should be replaced promptly to prevent further deterioration of the system. When replacing bearings, it is crucial to use the correct type and size and to properly preload them according to the manufacturer's specifications. Furthermore, ensure that all seals are in good condition to prevent oil leaks and contamination. Proper assembly and torque are essential for the longevity of the final drive system.
To diagnose final drive problems, begin by listening for unusual noises, such as grinding or whining. Next, check the oil level and condition. If the oil is low or contaminated, drain and refill the final drive with the correct type of lubricant. Inspect the axle shafts for excessive play or looseness. If any of these issues are present, it may be necessary to disassemble the final drive for a more thorough inspection. Always consult the service manual for specific troubleshooting procedures and repair instructions.
The Power Take-Off (PTO) system on your John Deere 855 allows you to connect and power implements such as mowers, tillers, and balers. Proper operation and maintenance are crucial to ensure safe and efficient use of these implements. Before engaging the PTO, always make sure that the implement is properly attached and that all safety shields are in place. Never operate the PTO with the shields removed, as this poses a serious safety hazard. Additionally, ensure that the PTO speed is set correctly for the implement being used to prevent damage.
Regular maintenance of the PTO system includes lubricating the PTO shaft and slip clutch, as well as inspecting the PTO clutch for proper engagement and disengagement. A slipping PTO clutch can lead to reduced power transfer and overheating. If the clutch is slipping, it may need to be adjusted or replaced. Furthermore, check the PTO shaft for any signs of wear or damage, such as cracks or bends. Damaged PTO shafts should be replaced immediately to prevent failure and potential injury.
Repairing the PTO system often involves disassembling the PTO clutch and inspecting the friction plates, pressure plate, and release bearing for wear or damage. Worn or damaged components should be replaced with genuine John Deere parts. When reassembling the PTO clutch, it is crucial to properly adjust the clutch linkage to ensure smooth engagement and disengagement. Consult the service manual for specific adjustment procedures and torque specifications. Remember to always disconnect the PTO before performing any maintenance or repairs on the system to prevent accidental engagement.
The hydraulic pump is the heart of the John Deere 855's hydraulic system, responsible for generating the necessary pressure to operate various functions such as the loader, backhoe, and power steering. Diagnosing pump problems early can prevent more extensive damage to the entire hydraulic system. Start by visually inspecting the pump for any external damage, leaks, or unusual noises. Common symptoms of a failing pump include slow hydraulic operation, a whining or grinding sound during operation, and overheating of the hydraulic fluid. If you observe any of these symptoms, further investigation is required to determine the root cause of the problem.
To accurately diagnose a hydraulic pump issue, you'll need to perform a pressure test using a hydraulic pressure gauge. Connect the gauge to the appropriate test port on the hydraulic system and compare the readings to the specifications in this manual. A low-pressure reading indicates a potential problem with the pump, such as worn internal components or a faulty relief valve. If the pressure is within the specified range, but performance is still poor, the problem may lie elsewhere in the system. Before disassembling the pump, ensure the hydraulic system is depressurized and drained of fluid to prevent spills and potential injury.
Repairing a hydraulic pump typically involves disassembling it, inspecting individual components for wear or damage, and replacing any faulty parts. Common wear items include seals, bearings, and internal gears. It is crucial to use genuine John Deere replacement parts to ensure proper fit and performance. Thoroughly clean all components before reassembly, and lubricate them with hydraulic fluid to prevent dry starts. After reassembling the pump, perform a bench test to verify its operation before reinstalling it on the tractor.
Hydraulic valves control the flow of hydraulic fluid to different components in the system, directing power to the loader, backhoe, or other hydraulic functions. Over time, these valves can become contaminated with debris, leading to sticking, leaking, or improper operation. Regular servicing of hydraulic valves is essential for maintaining optimal hydraulic system performance. Start by visually inspecting the valves for any signs of leakage or external damage. Actuate the valve levers to check for smooth operation and any unusual resistance.
When servicing hydraulic valves, it is crucial to maintain cleanliness to prevent contamination of the hydraulic system. Before disassembly, thoroughly clean the exterior of the valve to remove any dirt or debris. Carefully disassemble the valve, taking note of the location and orientation of all components. Inspect the valve spools and bores for any signs of wear, scoring, or contamination. Clean all components with a suitable solvent and inspect the seals for damage or deterioration. Replace any worn or damaged parts with genuine John Deere replacements.
Reassembling hydraulic valves requires precision and attention to detail. Lubricate all components with hydraulic fluid before assembly to ensure smooth operation. Torque all fasteners to the specified values to prevent leaks and damage. After reassembly, test the valve for proper operation by actuating the levers and checking for smooth, responsive movement. If the valve continues to exhibit problems, further troubleshooting may be required to identify the root cause of the issue.
Hydraulic cylinders are responsible for converting hydraulic pressure into linear motion, powering the loader, backhoe, and other hydraulic functions. Over time, the seals in these cylinders can wear out, leading to leaks and a loss of hydraulic power. Rebuilding hydraulic cylinders is a cost-effective way to restore their performance and extend their lifespan. Before disassembling a hydraulic cylinder, carefully inspect it for any signs of damage, such as dents, cracks, or corrosion. Note the location of any leaks and the overall condition of the cylinder.
To rebuild a hydraulic cylinder, you will need to disassemble it carefully, taking note of the orientation of all components. Use a suitable spanner wrench to loosen the cylinder head and remove it from the cylinder barrel. Carefully slide the piston out of the barrel and inspect the piston rod for any signs of damage, such as pitting or bending. Replace any worn or damaged seals with genuine John Deere replacements. Clean all components thoroughly with a suitable solvent and inspect the cylinder barrel for any signs of scoring or wear.
When reassembling the hydraulic cylinder, lubricate all components with hydraulic fluid to ensure smooth operation. Install the new seals onto the piston and carefully slide it back into the cylinder barrel. Torque the cylinder head to the specified value using a torque wrench. After reassembly, test the cylinder for leaks by applying hydraulic pressure and inspecting the seals for any signs of leakage. If the cylinder continues to leak, further troubleshooting may be required to identify the root cause of the problem.
Hydraulic hoses and fittings are essential for transferring hydraulic fluid throughout the system. Over time, these hoses can become brittle, cracked, or damaged, leading to leaks and a loss of hydraulic pressure. Regular inspection and replacement of hydraulic hoses and fittings are essential for maintaining a safe and reliable hydraulic system. Inspect the hoses for any signs of wear, such as cracks, abrasions, or bulges. Check the fittings for leaks, corrosion, or damage.
When replacing hydraulic hoses, always use hoses that are rated for the appropriate pressure and temperature. Ensure that the hoses are the correct length and have the correct fittings for your application. Before installing a new hose, flush it with hydraulic fluid to remove any debris or contaminants. When installing fittings, use a suitable sealant to prevent leaks. Tighten the fittings to the specified torque values to ensure a secure and leak-free connection.
After replacing hydraulic hoses and fittings, thoroughly inspect the system for leaks. Start the tractor and operate the hydraulic functions to check for proper operation. If you find any leaks, tighten the fittings or replace the hose as necessary. Regularly inspect hydraulic hoses and fittings to prevent costly repairs and ensure the safe operation of your John Deere 855. Always relieve hydraulic pressure before disconnecting any lines.
Troubleshooting hydraulic issues requires a systematic approach and a good understanding of the hydraulic system. Start by identifying the symptoms of the problem and gathering as much information as possible. Is the hydraulic system slow to respond? Is there a loss of hydraulic power? Are there any unusual noises or leaks? Once you have a clear understanding of the symptoms, you can begin to narrow down the possible causes. Consult the troubleshooting charts in this manual to identify potential problems and their solutions.
Common hydraulic issues include low hydraulic pressure, contaminated hydraulic fluid, faulty hydraulic valves, and worn hydraulic cylinders. Check the hydraulic fluid level and condition. If the fluid is low or contaminated, add fluid or replace it as necessary. Test the hydraulic pressure using a hydraulic pressure gauge. If the pressure is low, check the hydraulic pump and relief valve. Inspect the hydraulic valves for sticking or leaking. Rebuild or replace any faulty valves. Inspect the hydraulic cylinders for leaks or damage. Rebuild or replace any worn cylinders.
When troubleshooting hydraulic issues, it is essential to follow proper safety procedures. Always relieve hydraulic pressure before disconnecting any lines. Wear safety glasses and gloves to protect yourself from hydraulic fluid. Use caution when working around moving parts. If you are not comfortable troubleshooting hydraulic issues, consult a qualified technician. Properly maintaining your hydraulic system will extend its life and ensure the efficient operation of your John Deere 855.
The John Deere 855's steering and brake systems are crucial for safe and efficient operation. Regular maintenance and timely repairs are essential to prevent accidents and ensure optimal performance. Understanding the components and their functions is paramount before attempting any service procedures. This chapter will provide detailed instructions for inspecting, adjusting, and repairing the steering and brake systems on your John Deere 855. Always remember to prioritize safety by disengaging the engine, setting the parking brake, and using proper personal protective equipment before beginning any maintenance or repair task.
The steering system allows the operator to control the direction of the tractor. Over time, wear and tear on the steering components can lead to excessive play, making it difficult to steer accurately. Begin by inspecting the steering linkage for any signs of wear, damage, or loose connections. Pay close attention to the tie rod ends, steering knuckles, and steering gear. If any of these components are worn or damaged, they should be replaced immediately to maintain proper steering control. Neglecting these issues can lead to unsafe operating conditions and potential accidents.
Adjusting the steering linkage can often eliminate play and improve steering response. Locate the adjustment points on the tie rods, typically consisting of threaded sleeves and clamps. Loosen the clamps and rotate the sleeves to adjust the length of the tie rods. Remember that adjusting one tie rod will affect the toe-in or toe-out of the front wheels. It is crucial to refer to the manufacturer's specifications for the correct toe setting. After making adjustments, tighten the clamps securely to prevent the sleeves from rotating. Re-check the steering for any remaining play and readjust if necessary. Always ensure both left and right steering is equal in rotation.
If the steering gear itself is worn or damaged, it may require repair or replacement. Overhauling a steering gear typically involves disassembling the unit, inspecting the internal components, and replacing any worn or damaged parts. This task often requires specialized tools and a thorough understanding of the steering gear's internal workings. Therefore, you can consider taking the steering gear to a qualified technician. If repair is not feasible, a new or remanufactured steering gear may be the best option. Ensure that the replacement steering gear is compatible with your John Deere 855.
The brake system is critical for stopping the tractor safely and effectively. The John Deere 855 typically employs a drum brake system. Regular inspection of the brake components is essential to ensure proper function. Start by checking the brake pedal travel and resistance. Excessive travel or a spongy feel can indicate a problem with the brake system. Inspect the brake drums for cracks, damage, or excessive wear. Check the brake shoes for lining thickness and contamination. Brake shoes with worn or contaminated linings should be replaced.
Adjusting the brakes can compensate for wear and restore proper braking performance. Locate the brake adjustment mechanisms, typically located near the brake drums. Consult the manufacturer's specifications for the correct adjustment procedure. Using the adjustment mechanism, increase or decrease the distance between the brake shoes and the brake drum. Be careful not to over-tighten the brakes, as this can cause them to drag and overheat. After adjusting the brakes, test them to ensure they are functioning correctly. Remember to adjust both brakes equally to maintain balanced braking performance.
Replacing the brake shoes is necessary when they are worn beyond their service limit. Remove the brake drum to access the brake shoes. Disconnect the brake springs and remove the old brake shoes. Clean the brake drum and backing plate thoroughly before installing the new brake shoes. Install the new brake shoes and reconnect the brake springs. Reinstall the brake drum and adjust the brakes as described above. Finally, verify the correct brake pedal travel after brake shoe replacement.
If the brake system becomes contaminated with air, the brakes may feel spongy or ineffective. Bleeding the brakes is necessary to remove the air and restore proper braking performance. Locate the bleeder screws on the brake cylinders, usually on the back of each brake assembly. Attach a clear hose to the bleeder screw and submerge the other end of the hose in a container of brake fluid. This prevents air from being drawn back into the system.
Have someone slowly depress the brake pedal while you open the bleeder screw. Allow the brake fluid to flow until no more air bubbles are visible in the hose. Close the bleeder screw before releasing the brake pedal. Repeat this process several times for each brake cylinder, until all the air is removed from the system. Be sure to check the brake fluid level in the master cylinder regularly and replenish as needed during the bleeding process. Using the correct brake fluid specified by John Deere is imperative to ensure proper operation.
After bleeding the brakes, test the brake pedal for a firm feel. If the brakes still feel spongy, repeat the bleeding procedure. Check for any leaks in the brake lines and fittings. If necessary, tighten or replace any leaking components. Proper brake bleeding will ensure optimal brake performance and enhance the safety of your John Deere 855. If you are uncomfortable performing this procedure, seek assistance from a qualified mechanic.
The front axle of your John Deere 855 is a critical component, responsible for steering and absorbing shocks. Regular maintenance is paramount to ensuring optimal performance and preventing costly repairs down the line. Neglecting the front axle can lead to uneven tire wear, poor handling, and even potential safety hazards. A key part of the maintenance routine is checking and replenishing the lubricant in the front axle housing. The recommended lubricant type and fill level are specified in the technical manual; always adhere to these specifications to prevent damage or malfunction.
In addition to lubrication, inspect the front axle components for signs of wear or damage. Pay close attention to the kingpins, tie rod ends, and axle bearings. Worn or damaged parts should be replaced immediately to maintain proper alignment and steering responsiveness. Look for excessive play in the steering linkage, as this can indicate worn tie rod ends or kingpins. Also, regularly inspect the axle housing for cracks or leaks; any signs of damage should be addressed promptly to prevent further deterioration. Always use genuine John Deere replacement parts to ensure proper fit and longevity of the repair.
Front-wheel assist models require additional maintenance. Regularly inspect the drive shafts, universal joints, and front differential for wear and damage. Lubricate these components according to the manufacturer's recommendations. Check the engagement mechanism of the front-wheel assist system to ensure proper operation. Any unusual noises or vibrations during front-wheel assist operation should be investigated immediately. Remember that the front axle is subject to significant stress, especially during heavy-duty operations, so thorough and consistent maintenance is absolutely essential.
The rear axle assembly on your John Deere 855 is the workhorse responsible for transmitting power to the wheels. A robust design allows it to handle significant loads and demanding terrain; however, regular inspection is crucial for maintaining its integrity and extending its service life. Start by visually inspecting the axle housing for any signs of leaks or damage. Oil leaks around the axle seals indicate potential seal failure and should be addressed immediately to prevent contamination and lubricant loss. Listen for any unusual noises emanating from the rear axle area during operation, such as whining, grinding, or clicking. These noises could indicate worn gears, bearings, or other internal components.
Check the condition of the axle bearings. Excessive play in the axle shafts can be an indication of worn bearings. With the tractor safely supported, attempt to move the axle shafts laterally; any significant movement indicates the need for bearing replacement. Furthermore, ensure that the rear axle vent is clear and unobstructed. A clogged vent can cause pressure buildup within the axle housing, leading to seal failure and lubricant leaks. Clean the vent regularly to prevent these issues. Correct lubrication and adequate venting are essential to the rear axle's longevity.
Periodically inspect the axle mounting points to the frame. Ensure that all bolts are properly torqued to specification. Loose mounting bolts can cause stress and vibration, potentially leading to frame damage or axle failure. Also, inspect the condition of the axle shafts themselves for any signs of bending, cracking, or corrosion. Damaged axle shafts should be replaced immediately to prevent catastrophic failure. Always consult the service manual for specific torque specifications and maintenance procedures related to your John Deere 855's rear axle assembly.
The frame provides the structural backbone of your John Deere 855, supporting all major components and absorbing the stresses of operation. A sound frame is essential for maintaining the tractor's integrity, handling, and overall safety. Therefore, regular and thorough frame inspections are paramount. Begin by visually examining the entire frame for any signs of cracks, bends, or corrosion. Pay particular attention to areas around welds, stress points, and mounting locations for other components. Use a bright light and a magnifying glass to aid in the detection of subtle cracks that may not be readily apparent.
If you discover any cracks in the frame, they must be repaired promptly by a qualified welder. Ignoring cracks can lead to catastrophic frame failure, resulting in significant damage to the tractor and potential safety hazards. Prior to welding, thoroughly clean the area around the crack to remove any dirt, grease, or rust. Use proper welding techniques and materials to ensure a strong and durable repair. Reinforce the repaired area if necessary, especially in high-stress locations. After welding, grind the weld smooth and apply a protective coating to prevent corrosion. Seek out the advice of a certified welding professional before undertaking any frame repair.
Corrosion is another common issue that can weaken the frame over time. Remove any surface rust with a wire brush or abrasive pad. Apply a rust-inhibiting primer followed by a durable topcoat to protect the frame from further corrosion. Regularly washing and cleaning the tractor can also help prevent the buildup of dirt and debris that can accelerate corrosion. When inspecting the frame, also check the condition of all mounting bolts and fasteners. Ensure that they are properly torqued to specification. Loose or missing fasteners can cause undue stress on the frame and lead to component damage. Regular frame inspection and maintenance are crucial for preserving the integrity and extending the life of your John Deere 855.
Maintaining your John Deere 855's mower deck is crucial for achieving a pristine cut and ensuring the longevity of the attachment. Regular inspection should include checking the blades for sharpness, balance, and any signs of damage such as bends or cracks. Dull blades tear grass rather than cutting it cleanly, leading to a browning effect and making your lawn susceptible to disease. Sharpen or replace blades as needed, always ensuring you maintain proper balance to prevent excessive vibration during operation. Balancing can be done using a blade balancer, a relatively inexpensive tool available at most lawn and garden supply stores. Imbalance can put undue stress on the spindle bearings, leading to premature failure.
Beyond the blades, also inspect the deck shell for rust, corrosion, or damage from impacts. Address any rust immediately with a wire brush and appropriate rust-inhibiting paint to prevent further degradation. Check the spindle bearings for play or excessive noise; these bearings are critical for smooth blade rotation. Grease the spindle bearings regularly according to the manufacturer's recommendations. Finally, ensure the deck is properly leveled to provide an even cut across the entire mowing area. An uneven deck can result in scalping or uneven grass height.
The loader attachment is a versatile tool for your John Deere 855, but it requires consistent servicing to operate safely and effectively. Start with a thorough visual inspection of the hydraulic cylinders, hoses, and fittings. Look for any signs of leaks, cracks, or damage. Hydraulic fluid leaks not only reduce the loader's performance but also pose an environmental hazard. Replace any damaged hoses or fittings immediately, and ensure all connections are tight. Furthermore, regularly check the hydraulic fluid level in the reservoir and top it off as needed with the appropriate type of fluid specified in your operator's manual.
Inspect the loader arms and bucket for any signs of bending, cracking, or excessive wear. Address any structural damage promptly to prevent catastrophic failure during operation. Grease all pivot points and bushings according to the maintenance schedule. Proper lubrication reduces friction, minimizes wear, and ensures smooth loader operation. Pay close attention to the bucket pivot points, as these areas are subject to heavy loads and significant wear. Regularly check the bucket cutting edge for wear and replace it when necessary to maintain efficient digging and loading performance.
Preparing your John Deere 855 for winter often involves installing a snowblower attachment. When installing the snowblower, always refer to your operator's manual for specific instructions and safety precautions. Ensure the attachment is properly aligned and securely fastened to the tractor's frame. Double-check all connections, including the PTO shaft, hydraulic lines (if applicable), and any electrical connections for the chute rotation. Make certain that the PTO shaft is the correct length and that the safety shields are properly installed to prevent entanglement. Before operating the snowblower, perform a test run in a safe area to ensure all functions are working correctly, including the chute rotation and deflector adjustment.
When the snow season is over, proper removal and storage of the snowblower are essential for preventing damage and prolonging its lifespan. Disconnect the PTO shaft, hydraulic lines, and electrical connections. Carefully remove the attachment from the tractor, following the reverse order of the installation process. Clean the snowblower thoroughly, removing any accumulated snow, ice, or debris. Inspect the attachment for any signs of damage or wear, and address any issues before storing it. Store the snowblower in a dry, protected location to prevent rust and corrosion. Covering the snowblower with a tarp or storing it indoors is recommended.
The engine is the heart of your John Deere 855, and any problems here can significantly impact performance. Start by verifying the basics: adequate fuel levels, a clean air filter, and a charged battery. Inspect the fuel lines for kinks or leaks that could restrict fuel flow. A clogged fuel filter can also starve the engine, so consider replacing it as a preventative measure. Listen carefully to the engine sound during starting and operation. Unusual noises, such as knocking or hissing, can indicate internal damage or leaks that require immediate attention.
If the engine is hard to start, check the glow plugs. These preheat the combustion chamber to aid in cold starting. Use a multimeter to test the glow plugs for continuity. If any are faulty, replace them. Also, confirm that the fuel shutoff solenoid is functioning correctly. This solenoid controls the fuel supply to the engine, and a malfunction can prevent the engine from starting. Ensure that the wiring harness connected to the solenoid is secure and free from corrosion. A visual inspection of the engine compartment is crucial, looking for signs of oil leaks, coolant leaks, or frayed wiring.
For low power or excessive smoke, consider a compression test. Low compression can indicate worn piston rings, valve problems, or a blown head gasket. A compression test will give you a definitive answer and guide you to the source of the problem. Blue smoke usually indicates burning oil, while black smoke suggests incomplete combustion due to a rich fuel mixture or restricted airflow. White smoke can indicate coolant entering the combustion chamber, often due to a cracked head or blown head gasket.
The transmission is responsible for transferring power from the engine to the wheels, so issues here can lead to a loss of mobility. Begin by checking the transmission fluid level. Low fluid can cause slipping or complete failure. Inspect the fluid for signs of contamination, such as a milky appearance (indicating water contamination) or a burnt smell (indicating overheating). A drain and refill with fresh fluid may be necessary. Check the external linkage for any binding or looseness. Make sure all the linkages are properly lubricated, and any bent linkages are corrected, as they cause sluggish shifting.
If the transmission is slipping, it could be due to worn clutches or bands. Slipping can also be caused by low hydraulic pressure within the transmission. The John Deere 855 utilizes a hydrostatic transmission. If that is not working, start by cleaning the transmission screens as these can get clogged and cause it to malfunction. After that, you will need to remove the transmission and have it fully tested. Transmission work is best left to an experienced technician or a certified repair shop with the necessary tools and equipment. A thorough inspection of the transmission internals is vital to determine the extent of the damage and the necessary repairs.
Unusual noises, such as grinding or whining, can indicate internal damage to gears or bearings. These noises may be more pronounced at certain speeds or in certain gears. A leaking transmission can lead to low fluid levels and eventual failure. Inspect all seals and gaskets for leaks, and replace them as needed. Be sure to use the correct type of sealant or gasket material to ensure a proper seal.
The hydraulic system powers many functions on the John Deere 855, including the loader, backhoe, and steering. Start by inspecting the hydraulic fluid level in the reservoir. Low fluid can cause cavitation and damage to the hydraulic pump. Check the fluid for contamination, such as dirt or water. Contaminated fluid can damage the pump, valves, and cylinders. A fluid analysis can reveal the level of contamination and the type of contaminants present.
Slow or weak hydraulic performance can be caused by a worn or damaged hydraulic pump. Use a pressure gauge to test the pump's output pressure. Compare the reading to the specification in the service manual. A low-pressure reading indicates a problem with the pump or a restriction in the system. Check the hydraulic lines and hoses for leaks or kinks. Leaks can cause a loss of pressure, while kinks can restrict flow. Replace any damaged lines or hoses.
Malfunctioning hydraulic valves can also cause problems. These valves control the direction and flow of hydraulic fluid. If a valve is sticking or not functioning properly, it can cause a loss of function or erratic operation. Clean and inspect the valves for damage or wear. Replace any faulty valves. Check hydraulic cylinders for leaks or damage. Leaks can cause a loss of power, while damage can prevent the cylinder from extending or retracting properly. Rebuild or replace any damaged cylinders.
The electrical system provides power for starting, lighting, and other accessories. Begin by inspecting the battery terminals for corrosion. Clean the terminals with a wire brush and apply a corrosion protectant. Check the battery voltage with a voltmeter. A fully charged battery should read around 12.6 volts. If the voltage is low, charge the battery or replace it if it's unable to hold a charge. Inspect the wiring harness for damage or corrosion. Look for frayed wires, loose connections, or signs of rodent damage.
If the engine won't start, check the starter motor and solenoid. Use a voltmeter to test the voltage at the starter motor when the key is turned to the start position. If there's no voltage, check the starter solenoid and the wiring between the key switch and the solenoid. A faulty solenoid can prevent the starter motor from engaging. Check the fuses and relays for any blown or damaged components. Replace any faulty fuses or relays with the correct amperage and type. A blown fuse is often a sign of a short circuit in the wiring.
If the lights aren't working, check the bulbs and the wiring to the lights. Use a test light to check for voltage at the bulb socket. If there's no voltage, check the wiring, switches, and fuses. Ensure the bulbs are the correct type and wattage. Damaged or corroded wiring can cause shorts or open circuits. Repair or replace any damaged wiring. Always disconnect the battery before working on the electrical system to prevent shorts and potential damage.
Maintaining your John Deere 855 according to the recommended service intervals is crucial for its longevity and optimal performance. Regularly scheduled maintenance allows you to identify potential problems early on, preventing costly repairs down the line. These intervals are typically defined by operating hours or calendar time, whichever comes first. Adhering to these schedules ensures that critical components like the engine, transmission, and hydraulic system receive the necessary attention, minimizing downtime and maximizing the lifespan of your investment. Consult your John Deere 855 operator's manual for the specific maintenance schedule tailored to your model.
Ignoring these schedules can lead to a gradual degradation of performance, increased fuel consumption, and ultimately, component failure. Think of preventative maintenance as an investment in your tractor's future. By spending a little time and money on regular upkeep, you'll avoid much larger and more disruptive expenses later. This meticulous approach keeps your 855 running smoothly and efficiently, ready to tackle any task you throw its way. Always document the maintenance performed, noting the date, hours, and specific services completed.
Proper fluid levels are the lifeblood of your John Deere 855. Regular checks are essential to ensure that the engine, transmission, and hydraulic system are adequately lubricated and cooled. Low fluid levels can lead to overheating, excessive wear, and ultimately, component failure. Conversely, overfilling fluids can also cause issues, such as seal damage and reduced efficiency. Familiarize yourself with the location of all fluid reservoirs and the correct dipstick markings or sight glasses for accurate level checks.
When checking fluid levels, ensure the tractor is parked on a level surface with the engine off and allowed to cool. This ensures accurate readings. Use the recommended fluids specified in your operator's manual. Mixing different types of fluids can compromise their properties and damage internal components. Always dispose of used fluids responsibly, following local environmental regulations. Regular fluid replacements are also necessary to remove contaminants and ensure optimal performance.
Filters are the guardians of your tractor's vital systems, preventing contaminants from circulating and causing damage. Engine oil filters, fuel filters, air filters, and hydraulic filters all play a crucial role in maintaining the cleanliness and integrity of the fluids and air that power your John Deere 855. Clogged or dirty filters restrict flow, reduce efficiency, and can lead to serious engine or hydraulic system problems. Regular filter replacements are a simple and cost-effective way to protect your investment.
Always use genuine John Deere filters or equivalent quality replacements to ensure proper fit and filtration efficiency. Cheaper, aftermarket filters may not meet the same standards and could compromise your tractor's performance. When replacing filters, be sure to follow the instructions in your operator's manual carefully. Properly prime filters before installation to prevent dry starts and potential damage. Dispose of used filters responsibly. Pay close attention to the service interval for each filter type, as they vary depending on operating conditions and the type of fluid being filtered.
Greasing lubrication points is vital for reducing friction and wear on moving parts. Your John Deere 855 has numerous grease fittings located throughout the chassis, including on steering linkages, loader arms, PTO shafts, and other moving joints. Regularly lubricating these points ensures smooth operation, prevents premature wear, and extends the lifespan of critical components. Consult your operator's manual for the location of all grease fittings and the recommended lubrication intervals.
Use a high-quality lithium-based grease that is suitable for agricultural equipment. Before greasing, clean the grease fitting with a rag to remove any dirt or debris. Apply grease until fresh grease appears, indicating that the old grease has been purged. Avoid over-greasing, as this can attract dirt and debris. Pay particular attention to lubrication points that are exposed to harsh conditions, such as dust, mud, or water, as these may require more frequent lubrication. A little grease goes a long way in preventing costly repairs and ensuring the long-term reliability of your John Deere 855.