Fighters against corrosion have made gains

Press, Volume CX, Issue 32406, 19 September 1970, Page 15

Fighters against corrosion have made gains

Johnson research engineers have spent much time fighting problems

of corrosion. One of the results of their researches has been the use of aluminium alloys —the best obtainable for

corrosion control. Other improvements included those listed here: All aluminium surfaces have been iyfanited (Ly-

fanited—a chemical sur-face-treating process that improves corrosion resistance and provides a better paint-holding surface). All critical interior water passages are coated with an extremely durable corro-sion-resistant red sealer that penetrates the tinest exposed interior surface. All exterior surfaces are prime coated with zinc cromate—the final finish is baked enamel. All exposed fasteners (nuts, bolts, screws, washers, and so on) are of stainless steel. All non-stainless steel parts under the motor covers cadmium plated (with three times the normal amount of cadmium). All stainless steel parts passivated—a chemical-dip process that adds to the corrosion resistance of stainless steel. All screw threads lubricated with wool grease. The Johnson ttiermostatically-con-trolled cooling assures running temperatures high

enough to prevent condensation. Johnson has attacked corrosion in other militant ways: Stainless steel drive shafts and propeller shafts. Chrome or nickel carbide plated seal areas. Anodised die-cast aluminium water pump housing. Bronze bushings where propellers are fitted to stainless steel propeller shafts. Breaker points electropolished to prevent humidity corrosion. Electric start and electric choke switches sealed with rubber boots. Shift linkage uses brass or stainless steel parts. Rubber boot covers on spark plugs. Sealed remote control cables. Stainless steel used for exposed springs.