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    2009 Honda Truck Ridgeline 4WD 3.5L MFI SOHC VTEC 6cyl

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    Radiator Cap

    Radiator Cap Operation:

    The radiator cap fits the filler opening on top of the radiator. It controls the pressure and vacuum inside the cooling system and prevents leakage. The pressure raises the boiling point of the coolant, and a pressure valve relieves excess pressure. A vacuum valve in the cap prevents a vacuum buildup in the radiator as the system cools.

    How To Instructions:

    Inspect - Check for obvious problems.
    Test - Give it an in-depth diagnosis.
    Replace - Out with the old, in with the new.

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