2004-2005 Honda TRX450R Factory Sevice Manual, Page 119Get this manual
COOLING SYSTEM Co nnect the siphon hose to he radiat or filler neckFill and bleed th cooli ng system (page 7-7)Ahe bleed inginst all bot front fen ders (page 3-5)
WATER PUMP
MECHANICAL SEAL INSPECTION
Disconnect the drain hose from the drain pipe of the right crankcase coverCheck the drain pipe for signs of coolant leakageIf there is leakagethe mechanical seal is defective and it must be repl aced