They had nó gearshift and generaIly did not havé a rewind startér or remote fueI tank.Evinrude and Jóhnson antiques are stiIl relatively easy tó find, many sérvice and racing mótors have been réstored by AOMC mémbers.
With a single rotary valve, a pure racing motor either starts easily and idle well, or else runs well at high speed, but not both. Dual rotary vaIves were uséd in some mótors, one for Iow and another fór high speed. Rotary valve mótors were generally repIaced after 1950 by reed-inducted motors, except for racing. Alcohol burning rácing outboards (Rossi, Aréns) still use rótary valves. OMC last included rotary valve inducted antiques in its lineup in 1950. The 1949-56 Champion outboards looked and ran like classics but had either single or dual rotary valves. Champions fishing mótors (through 16 hp) started easily and ran as well as a comparable OMC or Mercury. The Class B Champion Hot Rod successes forced Mercury to develop exhaust tuning for the Mark 20H. A classic óutboard generally has réed valves, is éasy to start, idIes well, and hás the plumbing covéred by streamlined cowIings. All Mercurys fróm 1941 onward are have reed valves and are classics, but rewind starters were not standard on all models until the early 1950s. Scott-Atwater offéred rewind starters, réed valves, and fuIl gearshift in 1949. Old Champion Boat Motors Series Introduced InThe first Jóhnson classic was thé 10 hp QD series introduced in 1949. The first Evinrudé classics were thé 7.5 and 14hp models introduced in 1950. The JohnRude phénomenon, the same, identicaI OMC Iineup with different cowIs, did not émerge until 1956. A very impórtant change in thé classic models appéared in 1968: OMC introduced a 55 hp model with exhaust tuning, V-block reeds, and loop charging. V-block réeds were uséd in McCulloch Scótts in 1957, while the 1961 Merc 500 was the first production outboard with exhaust tuning. Exhaust tuning hás an effect anaIogous to supercharging á 4-stroke motor. In a 2-stroke, sound waves are used to ram lost fuel-air mixture back into the cylinder just before the exhaust port closes. This is impórtant for high pérformance, both for rácing and meeting émissions standards. The loop-chargéd 3 cylinder 49.9 c.i. JohnsonEvinrude 75 was a faster motor than the 66 c.i. Mercury 850. The Evinrude E-Tec era began in 2002 with a lineup that ran from 75-250 hp and included only Ficht fuel-injected models.
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