Operation & Maintenance Manual for WP7 Euro Ⅵ Vehicle Diesel Engine Table 2-5 Maintenance specification of the engine 10 Item 1st inspection Regular inspection Level 1 maintenance Level 2 maintenance Level 3 maintenance Level 4 maintenance Change oil (at least once per year) ● ● ● ● ● ● Replace the oil filter element Each time when changing diesel engine oil Inspect and adjust the valve clearance ● ● ● ● ● Replace filter element of the fine fuel filter ● ● ● ● Wash coarse fuel filter or replace the element ● ● ● ● Inspect coolant amount and add to required amount ● ● ● ● ● ● Change the coolant Once a year Tighten clips on cooling pipe ● Tighten air inlet pipe, hose and flange connections ● ● ● ● ●