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Check for oil or water leaks and the oil level using the dipstick.
Replace engine oil and filter as per periodic maintenance schedule; first replacement at 50 hours.
Be careful of heat sources during fuel filter replacement; evacuate air using the fuel feed pump.
Check antifreeze ratio before winter, add as needed, and clean radiator fins.
Discharge radiator water using the hose; add antifreeze to prevent corrosion in hot weather.
Frequently check air filter in dirty conditions; use pressurized air; engine performance depends on air intake.
Check tightness of fuel pipe connections and radiator hose clamps with a suitable wrench.
Replace V-belt without removing radiator; tighten via alternator; check tension by 1-2 cm deflection.
Disassemble cylinder head cover to adjust valve and rocker arm gaps based on engine temperature.