i have an oil pump on my 75 that i think is going out... the pump is supposed to be new, however, the heads are not getting any oil. furthermore, the pump never produces more than 25% max pressure on the gauge in the dash. the gauge and sender are new. when the vehicle is cold, the gauge reads 25%, however, when the engine heats up, it drops to just above the L mark. i have tried different grades of oil. none have helped. i was told that when a pump starts to go out, it acts in this manner. it will read a high or normal reading, and, as the engine warms, it will begin to drop off. is this true? it was also suggested that the pump may not be primed. do 2f's need to be primed in order to work correctly. i was going to go to the auto store and buy a priming rod, attach it to a drill, and spool it up just to see what it would do. what do you guys think?