From 1967 onwards, the fuel tank was fitted with an additional ventilation system consisting of various hoses and tubes. This T-piece connects the 15 mm breather hose between the fuel tank and the filler neck to the 4 mm thinner hose.
If you are in possession of a VW Type 3 equipped with an absorption carbon filter with which Volkswagen has responded to the demand for reduced CO2 emissions, you will also find this T-piece between the tank inlet and outlet pipes.
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