Yamaha - Water pump rep.kit - 6E5-W0078-1A-00Yamaha Water Pump Repair Kit Cooling System Service Kit 6E5 W0078 1A 00 Overview On these Yamahas, the water pump is one of the first things I check if theres any question about engine temp. Ive seen good motors get cooked just because the pump wasnt serviced in time. This kit is what you use to bring the cooling system back to life without cutting corners. Once its done right, you get solid water flow and peace of mind every time you fire it up. Key