JOHN DEERE 108 Service Manual

Overview of the John Deere 108 service manual

The John Deere 108 service manual provides a comprehensive reference for the maintenance, inspection, and repair of the 108 garden tractor. It consolidates essential specifications, diagnostic procedures, and step-by-step guidance to support technicians in keeping the machine operating safely and efficiently. Readers will find detailed illustrations and torque values, lubrication charts, and wiring diagrams that are critical for accurate service work. The manual emphasizes practical, hands-on procedures that can be performed with common shop tools, making it suitable for both professional technicians and experienced DIY enthusiasts. By following the documented procedures, operators can extend the life of their tractor and maintain optimal performance across mowing, tilling, and other typical tasks.

The document is organized to facilitate quick reference during maintenance tasks. It includes clear sequence recommendations, safety reminders, and notes on common wear items that require periodic replacement. A well-structured approach helps minimize downtime and avoids guesswork when diagnosing issues such as spark timing, carburetion, or hydraulic adjustments. The manual’s clarity supports consistent results, whether conducting routine maintenance like oil changes and air filter replacements or more involved repairs such as engine adjustments. Overall, it serves as a definitive guide to preserving reliability and ensuring safe operation of the John Deere 108 platform.

Safety precautions and PPE requirements

Safety is a central concern in the John Deere 108 service manual, with explicit instructions that prioritize the operator and technician’s well‑being. Before beginning any service task, disconnect the battery to prevent accidental starts, and ensure the machine is on a stable, level surface with the parking brake engaged. Use wheel chocks where appropriate to prevent movement, and engage proper Lockout/Tagout procedures when performing maintenance that could activate the controls. The manual also stresses the importance of using appropriate personal protective equipment (PPE) such as safety glasses, hearing protection, gloves, and steel-toed boots depending on the task at hand. Adhering to these precautions reduces the risk of injury from sharp components, moving parts, and unexpected machine startup.

During disassembly or repair work, follow torque specifications and proper lubrication guidelines to avoid component failure. The manual highlights the hazards associated with fuel, oil, and battery systems, recommending that technicians work in well-ventilated areas and away from open flames or sparks. It also advises on proper handling and disposal of fluids, as well as cleaning procedures to minimize exposure to harmful substances. By rigorously applying PPE, procedural cautions, and environmental considerations outlined in the manual, technicians can perform maintenance that is not only effective but also compliant with safety standards and best practices for engine and tractor service.

Initial inspection and preparation is a critical first step before performing any service on the JOHN DEERE 108. Begin by ensuring the work area is clean, well-lit, and free from distractions. Verify that you have all necessary tools, replacement parts, and the proper safety equipment, including eye protection and gloves. Carefully inspect the machine as it is uncrated or moved into the shop, noting any signs of shipping damage, missing fasteners, or obvious wear. Take detailed photos from multiple angles to document the as-found condition, which will aid in future maintenance and repair records. Establish a clear work plan and sequence of tasks to minimize downtime and ensure that essential systems remain protected during the inspection process.

Unpacking and inspection of components requires a methodical approach to avoid introducing damage or overlooking critical issues. Begin by removing panels and covers only after disconnecting the engine’s ignition or power source to prevent accidental starts. Check each component for corrosion, cracks, or loose connections, paying particular attention to the electrical harnesses, fuel lines, and cooling fins. Confirm that all mounting hardware is present and secure, and replace any missing or damaged fasteners with the correct grade and size as specified by Deere. Label and store removed parts systematically, so they can be reinstalled in the proper orientation during reassembly. This thorough initial check helps identify potential safety hazards and establishes a baseline for ongoing maintenance.

Electrical system safety and service indicators focus on protecting personnel and ensuring reliable operation. Before touching electrical components, disconnect the battery and isolate the ignition circuit to prevent accidental energization. Inspect battery terminals for corrosion and clean them if needed, using a non-conductive brush and appropriate contact cleaner. Evaluate all wiring for signs of abrasion, pinch points, or exposed conductors, and replace damaged sections with OEM-spec wiring. Test service indicators such as warning lights, hour meters, and diagnostic LEDs (if equipped) to confirm they illuminate correctly and reset after system checks. When in doubt, refer to the manufacturer’s wiring diagram for correct color codes and connector pinouts, and document any electrical fault codes observed during the inspection for follow-up repairs.

Proceeding with a careful, documented approach to initial inspection and preparation helps ensure a safe and efficient service process. Maintain a clean work surface and use labeled trays to organize fasteners and small parts. Recheck all safety guards, shields, and interlocks after completing the initial inspection to confirm they are correctly installed and functioning. If any component shows abnormal wear or damage beyond quick-fix tolerances, set the unit aside for replacement rather than attempting a temporary repair. Finally, compile a concise report detailing the condition of major subsystems, recommended actions, and estimated repair times, which will guide the service workflow and inform the customer of anticipated downtime.

In addition to general preparation, verify fluid levels and condition as part of the initial workflow. Check engine oil, hydraulic fluid, coolant, and fuel if present, noting any unusual coloration, emulsification, or sediment. Replace or top off fluids according to the manufacturer’s specifications, using the correct viscosity and grade for the operating environment. Dispose of any used fluids and contaminated rags according to local regulations and the shop’s environmental policy. Confirm that the air cleaner and fuel filtration systems are intact and free of obstructions, replacing filters if deterioration is evident. These steps help ensure reliable starting, prevent premature wear, and extend the service life of the machine while reducing the risk of introducing contaminants into sensitive systems.

Electrical system safety and service indicators require a disciplined testing protocol as the final preparatory step. After rechecking battery connections and fuel safety, perform a careful power-on test with the engine off to confirm there are no shorts or faults in the circuits. If the unit features diagnostic ports or onboard computer modules, use approved diagnostic tools to retrieve fault codes and confirm proper sensor operation. Document any findings and reset indicators after repairs, ensuring that the system returns to a stable state before attempting a full operational test. Concluding the initial inspection with a status summary helps technicians plan the next phase of service and provides the operator with confidence in the machine’s readiness for work.

Recommended tools and torque specifications

The JOHN DEERE 108 service manual requires a careful selection of hand tools, power tools, and precision measuring devices to perform maintenance and repairs accurately. Start with a complete metric and SAE set of combination wrenches, socket ratchets with both metric and standard sizes, and a full set of allen and Torx bits to accommodate various fasteners encountered on the mower. A torque wrench with a wide range is essential to verify fastener tightness to manufacturer specifications, along with a calibrated cabin or digital readout for precise measurements. A bat-wing or adjustable wrench, screwdriver set, pliers, and wire cutters are indispensable for common assembly tasks, while a rubber mallet or dead blow hammer ensures components seat without damage. For fluid management, keep a labeled collection of drain pans, funnels, and a graduated beaker for accurate measurement of lubricants and coolants. A digital multimeter is useful for diagnosing electrical circuits, and a service needle or vacuum pump may be required for fueling and carburetion work, depending on the engine configuration. Safety gear such as gloves, eye protection, and a sturdy work apron should be worn at all times to protect against sharp edges, hot surfaces, and chemical exposure.

Serious service on the JOHN DEERE 108 demands the correct torque specifications for fasteners across the chassis, deck, and engine mounting points. Begin by confirming the correct bolt sizes and thread pitches from the parts list, then consult the torque table in the manual to establish the required tightening values. Use a calibrated torque wrench and apply torque in the recommended sequence to avoid distortion or misalignment of components. For example, cylinder head bolts, deck-to-chassis fasteners, and engine mounting bolts each have distinct specifications that must be followed precisely. When torquing, use steady, even pressure and do not skip steps or reuse marked fasteners, as reusing can compromise clamping force and lead to leaks or improper seating. After torquing, recheck critical fasteners to ensure they remain within tolerance, including any hardware that may have loosened during initial operation or test runs. Documenting torque values during maintenance helps track wear patterns and supports future service intervals.

In addition to fixed torque values, some assemblies require a sequence of tightening to distribute clamping load evenly. Always adhere to the recommended pattern, such as crisscross or star patterns for multi-bolt flanges, to prevent warping. When replacing fasteners, use only OEM parts or equivalents rated for the same grade and strength; improper substitutes can fail under normal operating conditions. For electrical connections, ensure terminals are clean and tight, as loose connections can create resistance and heat buildup that may affect performance. Finally, keep a clean, organized workspace with labeled containers for fasteners by size and thread type, and maintain a parts inventory that can be cross-referenced with the manual to facilitate efficient disassembly and reassembly during service.

The JOHN DEERE 108 tractor uses a reliable engines and a simple, robust fuel system designed for field use and easy maintenance. When identifying the engine model, start by locating the rating plate or data tag, typically mounted on the valve cover or nearby the engine block. Record the exact model number, serial number, and displacement as these identifiers determine the correct service specifications and replacement parts. Visually inspect the engine for any signs of oil leaks, cracked hoses, or loose fittings, and verify that all connections are secure before attempting any maintenance. A clean, labeled workspace and a mirror or flashlight can help you access hard-to-see areas around the fuel and air intake sections without disturbing other components. Always consult the tractor’s stamped parts list to confirm compatible fuel system components and avoid cross-application issues with different model years.

Fuel quality is critical for consistent performance and longevity of the engine. Use clean, fresh gasoline with the appropriate octane rating as specified in the manual, and avoid mixed fuels or old stock that may contain moisture. Introduce only the quantity needed for immediate service; storing fuel in approved containers away from heat sources reduces the risk of degradation and varnish buildup inside the fuel system. When performing any fuel system maintenance, ensure the engine is cool and the ignition is turned off, and disconnect the battery to prevent accidental starts. Inspect the fuel cap, vent, and lines for cracks or wear, replacing any component that shows signs of deterioration to prevent air leaks and vapor lock. After servicing, always perform a visual fuel line check and, if possible, run the engine briefly to verify smooth operation and absence of leaks or misfiring.

Engine model overview and identification requires careful cross-checking of markings and component layout. Begin by comparing the observed engine layout with schematic diagrams for your specific model year to confirm the correct identification. Look for distinctive features such as carburetor type, intake manifold configuration, and exhaust routing, which help differentiate similar engines. Record any unique identifiers, including stamped numbers on the carburetor body, air filter housing, and fuel pump if present. If discrepancies arise between observed hardware and the expected configuration, stop work and consult the manufacturer’s loss-free parts catalog to prevent incorrect maintenance actions. Thorough documentation of the engine variant being serviced supports precise replacement parts ordering and reduces the risk of fitment issues during reassembly.

When performing fuel system cleaning, begin with a non-disruptive baseline assessment, including inspection of fuel lines for stiffness or cracking and confirmation of secure clamp points. Use an approved fuel system cleaner compatible with the engine design, adding the cleaner to a full or near-full tank according to the product instructions to avoid running the system lean or rich during cleaning. After circulating the cleaner through the lines, replace inline filters if the design requires it, and wipe away any residue from the exterior of the fuel components before restarting. If you encounter fuel delivery symptoms such as hesitation, misfire, or loss of power, perform a step-by-step diagnostic using manufacturer-recommended testing procedures, including pressure checks at the fuel rail or carburetor and vacuum readings where applicable. Conclude the maintenance by performing a brief engine run, verifying that RPM and throttle response are stable, and rechecking for leaks at all fittings and joints.

Guidelines for fuel quality emphasize maintaining clean storage practices, quality control during batching, and routine inspection of the entire fuel system. Use fresh fuel within the recommended shelf life and avoid ethanol blends if the engine is not designed for them, unless the manual specifies compatibility. Store fuel away from direct sunlight and heat sources, and use approved containers with sealed caps to prevent moisture ingress. Regularly drain water separators or sediment bowls if your model includes them, especially after storage or transport where water condensation can accumulate. Maintain good filtration by changing the fuel filter at intervals recommended by Deere or your equipment’s maintenance schedule, and always purge any air from the system after filter changes to prevent airlock and startup difficulties. Finally, document all fuel quality checks and cleaning intervals to create a reliable maintenance history that supports safe operation and predictable performance.

Lubrication and cooling systems

Effective lubrication is essential for the JOHN DEERE 108 to maintain optimal performance and extend component life. Begin by verifying the manufacturer’s recommended oil grade and viscosity, ensuring the oil meets the specified API service category. Establish a regular lubrication schedule that coincides with operating conditions, environmental temperature, and usage intensity. When performing oil changes, drain the old oil completely, replace the oil filter if applicable, and refill with the correct quantity to the full mark on the dipstick or sight line. Inspect all accessible lubrication points for leaks, secure fittings, and clean interfaces to prevent contamination from dirt and debris during service.

Oil specifications must align with the engine type and pump configurations installed on the unit. Use clean, approved substitutes if the original oil type is unavailable, but never mix multigrade oils beyond the recommended temperature range, as this can affect film strength and bearing protection. Regularly check oil level prior to operation, and observe for signs of oil degradation such as unusual exhaust color, burning odor, or visible residue around gaskets and seals. In dusty or sandy environments, consider more frequent oil changes to maintain filtration efficiency and protect internal components from abrasive wear.

Cooling system maintenance is critical to prevent overheating and ensure consistent performance. Start by inspecting the radiator, hoses, and clamps for cracks, swelling, or leaks, and replace any compromised parts promptly. Ensure the coolant mixture meets the prescribed ratio for the local climate, and verify that the system’s expansion reservoir is within the recommended level. When flushing the cooling system, disconnect the battery, remove the radiator cap only when the engine is cool, and use the specified flush solution to remove sediment and contaminants. After flushing, refill with the correct coolant specification and bleed air from the system as required to prevent air pockets that can impede heat transfer.

Regular checks should include monitoring the temperature gauge, fan operation, and thermostat performance. Inspect the water pump and belt drive for wear, tension, and alignment, replacing worn belts to maintain proper circulation. Clean debris from the radiator fins and surrounding areas to maximize airflow, and ensure the cooling fan engages at the appropriate engine temperature. For prolonged operation, implement a preventive maintenance routine that logs coolant changes, thermostat replacements, and radiator service to avoid unexpected overheating and to preserve engine longevity.

Electrical schematics interpretation is the foundation for diagnosing and repairing any electrical fault in the JOHN DEERE 108. Begin by locating the power source and tracing the main feed through the harness to the ignition switch, ignition coil, charging system, and gauges. A solid approach is to verify battery voltage at the positive terminal with the ignition off, then recheck after turning the key to the RUN position to confirm proper circuit continuity. When interpreting the schematic, note the color-coding of wires and the function of each connector, as this will help you quickly identify potential shorts, opens, or poor connections. Visual inspection should accompany schematic analysis to detect melted insulation, pinched wires, or brittle harness sections that may not be immediately apparent on paper. Use a multimeter to validate resistances, continuity, and battery voltage against the schematic's reference values, and document any deviations for future troubleshooting.

The starter, charging system, and battery maintenance section requires a methodical check of the starting circuit to ensure reliable cranking. Start by confirming the battery is properly rated for cold-cranking amps and that terminals are clean and tight, as poor connections can mimic more complex electrical faults. Inspect the starter solenoid and motor for signs of wear or overheating, and test the solenoid engagement by applying the appropriate control voltage from the ignition switch while monitoring the starter engagement. In parallel, verify the charging system by measuring the alternator output across a range of engine speeds, ensuring it maintains a consistent voltage within the prescribed specification; abnormal voltage may indicate a faulty regulator or alternator winding. Regular battery maintenance, including electrolyte level in non-sealed batteries and terminal treatment to prevent corrosion, prolongs system reliability and reduces unexpected electrical failures during operation. When performance issues arise, isolate the problem to either the battery, wiring harness, or the starter assembly using a step-by-step approach, recording readings at each stage to build repeatable diagnostic data.

Cutting deck and drive system maintenance

The cutting deck and drive system are critical to the performance and longevity of the JOHN DEERE 108. Regular inspection and precise adjustments ensure the mower delivers a clean, level cut and reliable propulsion across varied terrain. Start with a thorough visual check of the deck housing for cracks, bent brackets, or loose bolts, and ensure the mower is on a flat, stable surface before any maintenance. Remove any grass buildup from pulleys, shields, and belt paths to prevent slip and uneven tension. Use the proper tools and follow the manufacturer’s torque specifications when reassembling components to avoid over-tightening or missed fasteners. For safety, disconnect the spark plug wire and engage the parking brake before handling any moving parts or performing measurements.

Deck alignment begins with confirming that the front and rear of the deck sit parallel to the ground. Place a straightedge across the deck surface and measure from the blade tip to the straightedge at multiple points to ensure uniform clearance. If misalignment is detected, adjust the deck mounting brackets or lift linkage as required, rechecking evenly across all sides. A correctly aligned deck yields an even cut and reduces the likelihood of scalping on uneven ground. Always recheck after making any adjustment, and perform a test cut on a small, controlled area to confirm improvements before returning to regular mowing.

Belts must run true and with the correct tension to prevent slippage, wear, or belt failure. Inspect the drive belt and deck belt for cracks, fraying, glazing, or missing ribs, replacing any damaged belts promptly. Use a tension gauge or the manufacturer’s specified method to set belt tension precisely; overtensioning can shorten belt life, while undertensioning can cause slip and overheating. When replacing belts, route them according to the diagram on the belt cover, ensuring pulleys are aligned and free of debris. After belt installation, rotate the deck by hand to confirm smooth operation and proper belt seating before starting the engine.

Transaxle and drive belt inspection require careful attention to both components and mounting hardware. Check the transaxle oil level and inspect for signs of leakage or unusual wear around seals and gaskets. If a leak is detected, address it promptly using the correct gasket material and torque sequence, and replace seals as needed. Inspect the drive belt for wear in the area that contacts the transaxle pulley and replace the belt if any glazing or cracks are observed. When reinstalling the drive belt, ensure the belt is seated in all grooves and that pulleys run true without wobble. Regularly clean the belt path of grass clippings and dirt to prevent contamination that can accelerate wear. For optimal performance, perform a belt tension and alignment check after a full season of use or following any major impact event.

Transaxle maintenance also involves checking the cooling fins and external surfaces for dirt buildup that could impede airflow. Use a soft brush to remove loose debris and a damp cloth to wipe down surfaces, taking care not to introduce moisture into seals or bearings. Inspect mounting hardware for tightness and corrosion, tightening to the specified torque in a gradual, cross-pattern sequence. If the drive system experiences unusual vibration, slow speeds, or inconsistent traction, diagnose for misalignment, worn bearings, or damaged pulleys, and replace components as necessary. Maintain a routine service schedule that coincides with mowing seasons to preserve efficiency and minimize downtime, noting any changes in performance that could indicate wear or a developing fault.

The safety system and operator controls of the JOHN DEERE 108 are designed to ensure that the machine operates only when all parameters are in a known safe state. Begin by inspecting the primary safety interlocks to verify they engage properly whenever the operator presence mechanism is activated or deactivated. Confirm that the ignition switch responds only when the operator seat switch is in the correct position and that any pedal or lever positions correspond to the expected engine and transmission states. Regularly test the engagement verification system by starting the engine with the operator seated and the PTO or drive controls in the neutral or disengaged position, then attempt to move the machine only after confirming all safety indicators are active and steady. Document any intermittent or nonconforming signals, as these may indicate worn switches, loose wiring, or a failing relay that could compromise operator safety. When performing diagnostics, isolate the safety circuits carefully to prevent inadvertent starting, and use the manufacturer’s wiring diagrams to trace potential shorts or open circuits that could disable essential protections. Always ensure that guards, shields, and protective covers remain in place during operation and testing to avoid accidental contact with moving parts that could trigger safety interlock failures.

Control linkage and throttle systems on the JOHN DEERE 108 require precise adjustment and secure connections to maintain predictable engine response and safe operation. Begin with a thorough inspection of the throttle lever, linkage rods, and return springs for signs of wear, bending, or play. Check for proper alignment between the operator throttle control and the engine throttle linkage, ensuring that the mechanism does not bind at any point in its travel and that all pivots move freely without excessive play. When adjusting the throttle, reference the factory spec for idle and wide-open throttle (WOT) positions, and confirm that the throttle stops are set correctly to prevent over- or under-revving the engine. Inspect the connection points at the carburetor or fuel injection system to ensure there is no fraying cable or detached linkage, and replace any damaged components with approved OEM parts to preserve calibration. In addition to mechanical checks, verify that the control cables are properly tensioned and secured with heat-resistant crimps or clamps, and confirm that protective covers exist where cables pass near hot surfaces or sharp edges. Regular functional tests should be performed by engine running in a controlled environment, cycling from idle to WOT while monitoring RPM and engine response, with any lag, surging, or stiffness recorded for service actions.

The JOHN DEERE 108 is a reliable garden tractor, but like any complex piece of outdoor power equipment, it can exhibit symptoms that require careful diagnosis. Common issues include poor starting, misfiring, rough idling, loss of power, unexpected noises, and overheating. In many cases, symptoms point to a few probable culprits such as fuel supply problems, ignition faults, or air intake restrictions. A systematic approach helps you quickly identify the root cause without unnecessary disassembly. Start by verifying basic service conditions, including fresh fuel, clean air filters, clean spark plugs, and a properly rated battery charge. Documenting symptoms and operating conditions can also streamline the troubleshooting process and reduce downtime.

Common symptoms and likely causes include hard starting or no start, which often stems from stale fuel, a clogged carburetor, or a fouled spark plug. A rough idle or misfire frequently indicates ignition timing issues, spark plug fouling, or dirty intake valves. If the engine loses power under load, restricted air intake, a dirty fuel filter, or a clogged carburetor can be responsible, as can a weak or failing ignition coil. Overheating is commonly caused by cooling system blockages, improper air flow, or a stuck cooling fan, but it can also result from prolonged heavy operation with improper belt tension. Unusual noises such as knocking or grinding should prompt inspection of the deck pulleys, drive belts, and engine mounting to ensure components are properly aligned and secured. In each case, verify basic maintenance items first before proceeding to more invasive checks.

Step by step diagnostic procedures begin with a careful safety check: ensure the tractor is on a level surface, the engine is cool, and the ignition is in the off position before touching any components. Remove the spark plug and inspect it for wear, fouling, or improper gap; replace if necessary and verify proper gap according to the service manual. Check the fuel system, starting with the tank fuel quality and the condition of the fuel line and filter; replace any aging parts and ensure fuel is reaching the carburetor. If fuel delivery appears adequate, inspect the carburetor for varnish buildup and clean or rebuild as needed using manufacturer-approved methods. Examine the air intake system for restrictions, including the air filter element; a clean, dry filter is essential for optimal combustion and performance.

Continuation of diagnostic steps includes testing ignition components: verify that the spark plug produces a strong, blue spark by performing a grounded spark test, and inspect the ignition coil and wiring for cracks or corrosion. If compression is suspected, perform a controlled compression check to determine cylinder health, noting readings and comparing them to expected tolerances. For issues related to overheating, inspect the radiator-style cooling system and ensure the shroud, fins, and cooling passages are clear of debris. Confirm proper belt tension and alignment for both the drive and deck systems, replacing worn belts as needed to restore power transmission. Finally, after completing these checks, perform a controlled engine start and load test to verify that symptoms are resolved and that the engine runs smoothly under typical operating conditions.

The JOHN DEERE 108 requires a structured maintenance routine to ensure dependable operation and extended service life. Establishing a clear maintenance schedule helps prevent unexpected breakdowns and keeps performance at peak levels. Regular checks should cover the engine, electrical system, hydraulic components, and chassis, with particular emphasis on fluid levels, filter condition, and lubrication points. Adhering to manufacturer-recommended intervals reduces wear, improves efficiency, and supports safer operation in varying field conditions. Documenting each task performed creates a traceable record that can be reviewed by technicians for early detection of potential issues.

The preventive maintenance intervals for the 108 are best planned around engine hours and seasonal use. For most operators, a baseline routine includes daily quick inspections, a more thorough weekly check, and a comprehensive monthly service. Key tasks at the daily level involve verifying fuel, oil, and coolant levels, inspecting belts for wear, and checking for leaks or unusual noises. Weekly duties expand to air filter inspection, battery condition assessment, and a closer look at the cooling system. Monthly maintenance should include changing or cleaning filters as specified, testing electrical connections, and inspecting hydraulic fluids and hoses for signs of degradation or abrasion. Following these intervals helps maintain power, reliability, and overall safety in operation.

Establishing a robust service log and documentation practice is essential for the machine’s lifecycle. Each maintenance entry should include the date, engine hours (or a current equivalent), a description of tasks performed, parts replaced, and any observations or anomalies noted during service. Keeping a digital or printed log facilitates trend analysis, making it easier to predict when components will require attention before failure occurs. Include details such as fuel quality, oil viscosity, filter part numbers, and any torque specs used during reassembly to provide a useful reference for future work. Regularly review the log to identify recurring issues and to schedule preventative actions ahead of time, maximizing uptime and preserving the machine’s value.

When planning maintenance, reference the tractor’s user manual and service bulletin updates from John Deere for any model-specific changes to intervals or procedures. It is prudent to tailor the maintenance plan to the 108’s operating environment, as dusty or high-humidity conditions can accelerate wear on filters and seals. Ensure that maintenance tasks are performed with the engine off and the machine in a stable, level position, using appropriate safety practices and personal protective equipment. Maintaining organized records not only supports warranty compliance but also enhances resale value and confidence in the equipment’s ongoing performance. A disciplined approach to preventive maintenance, backed by thorough documentation, yields consistent, reliable operation of the JOHN DEERE 108 across seasons.