1639 1983-1986 Ford Bronco F Series 300 water pumpIf you have the Ford 300 4. 9L in your mid eighties Bronco and use the clutch fan you might be finding it runs a little hotter now. We designed a impeller with an increased vane count and a reduced impeller vane clearance to take care of the problem. It achieves greater flow rates, higher head pressure and a more efficient flow. The impeller color is due to Type II Class II military grade surface coating which protects against corrosive fluids.