To generate the high horsepower needed to pump the tremendous volume of fuel required by modern jet aircraft, Gorman-Rupp developed the split shaft approach on the O-Series self-priming pumps.Pumps can be mid-ship mounted, utilizing unused space between chassis frame members. Pump receives its power directly from truck engine.Pumps are aluminum construction with gray iron gear casing. Enclosed impeller is bronze or aluminum, seal is self-lubricating mechanical type.