The use of these heightening rings is required in any application where water might be splashed around a vented fill. The ring raises the opening between the fuel cap and fill an additional 3/8” above the deck surface thereby reducing the likelihood that splashed water will enter the fuel system through the breathing vent. The split version of the ring is designed for aftermarket use on existing installations. In most cases it allows the ring to be added without disconnecting fuel and vent hoses from the fill. For new OEM installations, rings are supplied without the split since they can then be installed before hoses are connected to the fill.
NOTE: The ring will not prevent water from entering the system if the cap becomes submerged or substantially flooded. If this situation exists, the fill/vent must be moved to a dry location or replaced with a sealed cap and a separate vent located elsewhere.
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