Abstract: A supplementary fuel system adds propane to the induction passage of an ethanol fueled engine to start and sustain operation of the engine at low temperatures. The propane flow is cycled on and off during cranking of the engine and the propane delivery pressure is varied with induction passage pressure.

Abstract: To prevent buckling and indentation of a panel being spot welded, a welding tip including an electrode of large load bearing and heat conducting surface is used to spread the load and also efficiently cool the workpiece. The large area electrode is a water cooled copper disk of large mass connected to a support arm by a coil spring. An electrical contactor on the support arm releasably engages the electrode to supply welding current thereto when welding pressure is applied to the workpiece by the welding gun. When the pressure is removed, the coil spring separates the electrode from the contactor.