Effect of “Sour” Gasoline on Fuel Hose Rubber Materials

Isolated fuel hose failures have been reported recently for cars equipped with electronic fuel injection systems. Although all of the factors responsible for failure are not known, “sour” or hydroperoxide-containing gasoline was suspected as being the main contributor. A study was undertaken, therefore, to determine the effect of “sour” gasoline on the tensile properties of fuel hose rubbers.

Fluorohydrocarbon rubbers exhibited outstanding resistance to attack and the lowest volume swell. Epichlorohydrin copolymer reverted as evidenced by extreme softening and various nitrile rubbers underwent additional vulcanization resulting in embrittlement.

Practical fluorohydrocarbon hoses have been constructed for the fuel injection system which resist degradation by “sour” gasoline.