2004-2009 Honda TRX450R/TRX450ER Service Manual, Page 170Get this manual
COOLING SYSTEM RADIATOR CAPSYSTEM PRESSURE INSPECTION Remove the radiator cap (page 9-5)Wet the sealing surfaces of the cap, then install the cap onto testerTOOLS: Cooling system pressure tester Cooling system adaptor SVTS4AH OTCJ33984A TESTER
Pressurize the radiator cap using the testerReplace the radiator cap if it does not hold pressure, or if relief pressure is too high or too lowIt must hold the specified pressure for at least secondsRADIATOR CAP RELIEF PRESSURE: 108137 kPa (1.11.4 kgfcm2,1620 psi)
Excessive pressure can damage the cooling system componentsDo not exceed 137 kPa (1.4 kgfcm2, 20 psi)
Pressure test the radiator, engine and hoses, and check for leaksRepair or replace components if the system will not hold the specified pressure for at least secondsRemove the tester and install the radiator capInstall the right front fender ('04'05: page 3-6, After '05: page 3-6)