TM 9-2320-364-102-68 Table 2-1. Operators Preventive Maintenance Checks and Services (Before) - CONT.LocationItemNo.IntervalItem toCheck/ServiceProcedureNot Fully MissionCapable if:NOTECold engines may have slightly higher oil pressure reading than a hot engine.11BeforeControls andIndicators -Cont.(k) Check oil pressure gage (14).Pressure gage must read between40 to 80 psi (276 to 552 kPa) withengine speeds between 1800 and2100 rpm. Minimum pressure forsafe operation is 30 psi (207 kPa).At idle, minimum oil pressureshould not be less than five psi (34 kPa).Engine oil pressureis not within allow-able pressures, andengine oil warninglight lights or warn-ing buzzer sounds.(l) Check that the AIR PRESSgage (15) is within the normaloperating range of 110 to 125 psi(758 to 862 kPa).Air pressure is notwithin limits or warning buzzersounds.(m) Check battery gages (16 & 17)for normal voltage output of 26 to30 volts and 13 to 15 volts.Voltage is not between the properoperating ranges.