TM 10-3930-664-24 Table 2-1.  Unit Preventive Maintenance Checks and Services Item Item to Not Fully Mission No. Interval Check/ Service Procedure Capable If: 1 ENGINE 250 Hours a Oil Change engine oil filter Filter shows Filter (para 2-20) signs of engine damage, ie; metal shavings, rust deposits. Quarterly b Air Check intake air filter. Filter Change filter if damaged or beyond cleaning (para 2-28). Check air restriction indic- ator for proper operation. Quarterly c Engine Check fuel lines for cracks, Fuel line is Fuel kinks, dents, or bends damaged or Lines Inspect fittings for signs fitting loose. of leakage.  Replace damaged lines (para 2-27). Quarterly d Belt Check engine alternator belt Belt is for wear / proper tension damaged. Replace if worn (para 2-54). Quarterly e Fuel/ Inspect fuel / water strainer Fuel shows Water for contamination Drain in signs of Strainer accordance with TM 10-3930- severe 664-10 Replace as required contamination. (para 3-9). Quarterly f Ether Check ether cylinder Replace Cylinder if empty (para 2-40). Annually g Radiator Flush cooling system and replace coolant (para 2-46). Annually h Cylinder Perform cylinder head valve Head / clearance adjustment Rocker (para 2-15). Arms 2-6