# Comprehensive Guide to Tractor Repair and Maintenance

I. Daily Maintenance Inspection 1. Pre-Start Daily Inspection ■ Engine Oil Check - Check the dipstick with the engine off, ensuring the oil level is between "MIN" and "MAX" - The oil should be transparent amber; if it turns black or contains metal particles, replace immediately ■ Cooling System - Check the coolant level in the radiator (should be 3-5 cm below the filler neck) - Look for signs of leakage (pay special attention to hose connections and the water pump) ■ Fuel System - Drain water from the bottom of the fuel filter (diesel models) - Check for air in the fuel lines (the hand primer should be firm with no sponginess) ■ Tires / Tracks - Tire pressure: 2.0-2.5 bar for dry field operation, 1.2-1.8 bar for paddy field operation - Track tension: sag at the midpoint should be 20-30 mm 2. Post-Operation Inspection - Clean the radiator grille (especially remove accumulated straw and weeds) - Check bolt tightness at all points (key areas: wheel hubs, drive shafts, suspension points) - Empty dust from the air filter dust cup (dry-type filter) II. Periodic Maintenance Schedule 1. Every 50 Hours - Replace the engine oil filter (first service recommended at 30 hours) - Lubricate all grease fittings (including steering tie rods, suspension pivots, etc.) - Check battery electrolyte (non-maintenance-free batteries) 2. Every 250 Hours ■ Engine Oil Change - Drain old oil while the engine is warm - CF-4 or higher grade diesel engine oil recommended - Typical capacity: 1.5-2 L for single-cylinder engines, 6-8 L for four-cylinder engines ■ Fuel Filter Replacement - Bleed air from the fuel system first - Fill the new filter with clean diesel before installation 3. Every 500 Hours ■ Transmission Oil Change - Use GL-5 80W-90 gear oil - Note the difference between oil for wet clutches and standard transmissions ■ Hydraulic System Maintenance - Replace the hydraulic oil filter element - Check hydraulic oil cleanliness (replace if below NAS Class 9) ■ Valve Clearance Adjustment - Perform with the engine cold - Typical values: intake valve 0.2-0.25 mm, exhaust valve 0.25-0.3 mm III. Common Fault Diagnosis and Troubleshooting 1. Engine Faults ■ Difficulty Starting - Check sequence: electrical → fuel → compression - In winter, check glow plug operation (resistance should be 0.6-1.0 Ω) ■ Insufficient Power - Check the turbocharger (if equipped) for oil leaks - Test fuel injector atomization (standard injection pressure 180-220 bar) 2. Transmission System Faults ■ Clutch Slipping - Check pedal free play (standard 15-20 mm) - Measure friction disc thickness (replace if below 2 mm) ■ Transmission Abnormal Noise - Distinguish between bearing damage (continuous humming) and gear damage (periodic knocking) 3. Hydraulic System Faults ■ Weak Lifting - Test the relief valve opening pressure (typically 12-15 MPa) - Check hydraulic pump volumetric efficiency (overhaul if below 80%) ■ Excessive Oil Temperature - Check the oil cooler for blockage - Confirm the hydraulic oil viscosity is appropriate (46# recommended for summer, 32# for winter) IV. Seasonal Maintenance Points 1. Winter Maintenance - Switch to low pour point diesel (-10# / -20# depending on temperature) - Insulate the battery (or remove and store indoors) - Add antifreeze to the cooling system (ethylene glycol type with freezing point ≤ -25°C) 2. Summer Maintenance - Strengthen cooling system cleaning (clean the radiator exterior weekly) - Reduce tire pressure by 0.2-0.3 bar to prevent blowouts - Check electrical system insulation (to prevent spontaneous combustion) V. Long-Term Storage Maintenance ■ Protective Treatment - Fill the fuel tank and add a stabilizer - Apply rust-preventive grease to exposed metal surfaces ■ System Protection - Start and run for 15 minutes monthly (or turn the crankshaft several revolutions) - Retract hydraulic cylinder piston rods to the shortest position ■ Storage Environment - Choose a dry, well-ventilated location - Cover with a dedicated tarpaulin (avoid direct sunlight) VI. Safety Repair Precautions ■ Work Safety - Hang a "Under Repair" warning sign during maintenance - Always use safety stands when lifting equipment (never rely on hydraulic support alone) ■ Professional Tool Usage - Torque wrench (critical bolts must be tightened to manual-specified torque) - Use dedicated guide tools for hydraulic cylinder disassembly and assembly ■ Environmental Requirements - Collect waste oil separately by category (never discharge directly) - Dispose of old filters as hazardous waste VII. Recommended Repair Tool List Tool Type Essential Tools Special-Purpose Tools Basic Tools Socket wrench set, torque wrench, screwdriver set Valve adjustment shim kit Specialty Tools Piston ring compressor, bearing puller Hydraulic tester Testing Equipment Digital multimeter, cylinder compression gauge Injector test bench VIII. Technical Information Sources - OEM repair manuals (including wiring diagrams and hydraulic schematics) - Manufacturer after-sales hotlines (most brands offer remote guidance) - Professional agricultural machinery repair forums (case sharing and experience exchange) Tip: For complex faults, contact an authorized service center. Disassembling precision components such as the ECU yourself may void the warranty. Keeping complete repair records is very important for resale transactions and value assessment.