FUEL TANK SENDING UNITS INSTALLATION NOTES
The "FT" series of Smith's petrol tank sending units are an antiquated design and require careful installation if leakage is to be avoided. Our reproductions incorporate fuel resistant rubber gaskets and seals which will provide improved performance over the original cork gaskets but still require careful installation.
One of the more common causes of leakage is through the screw thread holes, particularly if the screws or the mating threads on the tank flange are not in good condition. (Screw and washer kits are available under # L440A.)
Ensure that the mounting flange area is clean and apply a good grade of fuel resistant gasket cement to both the mounting gasket and the small lid gasket. We recommend Hylomar gasket sealer which is available locally.
The wire terminal should also be carefully checked for tightness but care should be exercised so that the terminal itself is not rotated which will result in breakage of the internal wire.
The very nature of this design is such that the hollow rheostat cavity will fill with fuel. This does not pose a safety hazard as long as the cover plate is in place.
Always disconnect the battery prior to removing the cover plate from an installed sending unit.
Due to variations in the inside flange diameter of some tanks, clearance or alignment problems may be encountered. It may be necessary to slightly grind or file the offending protruding area of the sending unit or a portion of the tank flange.