Ok my truck died while driving last month. When cranking the oil pressure gauge would not move at all. I decided HPOP w/STC fitting and ICP sounded right. Replaced that today and tried to start it and it is building oil pressure now but just cranks till battery dies. Hooked it to my shop cummins to help with cranking power but it will crank good for a few seconds and die. It turned over good about 6 times before batteries quit. Shouldn't it of started by then, or at least started to fire? I'm no diesel mechanic but I'm not a stranger to working on cars. I don't have and fancy gauges to check pressures or volts but if you have a idea I would appreciate any help.