ADAPTER FOR A CAPLESS FUEL TANK FILLER NECK TO TEST A FUEL TANK FOR LEAKS

A filler neck adapter to be inserted through the open fuel mouth of a capless filler neck of a fuel tank of a motor vehicle. The adapter has a hollow flow body to create a continuous flow path between a source of pressure or vacuum and the fuel tank to enable the fuel tank to he tested for leaks. A resilient seal surrounds the flow body of the adapter so as to lie between movable and stationary seal stops. A force-generating member is moved along the flow body to push the movable seal, stop and the seal towards the stationary seal stop. Accordingly, the seal is compressed between the movable and stationary seal stops so as to bulge outwardly towards and thereby create an air-tight seal against the fuel mouth of the filler neck. 1. For a capless fuel tank-filler neck of a motor vehicle by which fuel is delivered to a fuel tank of the motor vehicle , where the fuel tank tiller neck has an open fuel mouth through which the fuel flows to the fuel tank , and where the fuel tank filler neck has a closure positioned thereacross to block access to the fuel tank , an adapter to be removably attached to the fuel tank filler neck by which to couple a source of pressure or a source of vacuum to the fuel tank so that the fuel tank can be tested for leaks , said adapter comprising a hollow flow body to be inserted through the open fuel month and down the filler neck when said adapter is attached to the filler neck , said flow body having a length sufficient to engage and displace the closure positioned across the filler neck so as to permit access to the fuel tank , said adapter also comprising a seal carried by said flow body and positioned between said flow body and the fuel mouth of the fuel tank filler neck when said flow body is inserted through the fuel mouth , said seal being responsive to a force applied thereto whereby to cause said seal to be deformed and thereby move into air-tight sealing engagement with the fuel mouth of the fuel tank tiller neck while the fuel lank ...