The oil tank capacity of the P-40 N is 8 gallons. In the K and M models it is 12.9 gallons. Following is a table of weights of oil used: An engine-driven pump forces the oil from a storage tank to the engine at a pressure of from 60 to 80 psi. On the way back from the engine to the tank, the oil is cooled by a radiator which is regulated by manually operated shutters. These shutters also control coolanttemperature.

OIL PRESSURE AND TEMPERATURE GAGE Oil pressure and oil temperature are shown on a gage on the right side of the instrument panel. For normal operation, the oil pressure should be between 60 and 80 psi, temperature between 60' and 80' (maximum 95').