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Welcome to the Fall 2005 issue of OUTBOARD NEWS, an electronic newsletter for the outboard enthusiast. We regret that there were no spring or summer issues, due to the time constraints that exist in such a seasonal industry.
INDUSTRY NEWS Mercury has recently confirmed their plans to completely exit the traditional two-stroke outboard market. The last two-stroke was shipped on May 27, 2005. After that date, only four-stroke outboards will be available from the factory. The line-up will include small HP motors made by Tohatsu and mid-range motors made by Yamaha. A decision has been made in the lawsuit brought by Brunswick Corp against Yamaha Motors Corp. In the suit, Mercury claimed that Yamaha has been dumping outboard motors in the US marketplace, at artificially low prices, hurting US manufacturers. The decision is: yes and no. The US International Trade Commission has ruled that Yamaha has been dumping outboards, but that Mercury has not been harmed by it. If the Commission had ruled completely in Mercury's favor, tariffs would have been imposed on imports, thus raising their cost. Yamaha intends to adjust their prices to avoid the suit being refiled. This will effectively end a collaboration between Mercury and Yamaha that stretches back some 30 years. In recent years, Yamaha has been supplying 4 stroke powerheads to Mercury for some mid range engines. This will end when the contract expires in 2006. Bombardier Recreational Products has received the Clean Air Excellence Award from the EPA. for its Evinrude E-TEC outboard engine. This is the first time ever a marine engine manufacturer has received an award of Clean Air Excellence by the EPA. BRP has demonstrated that with the new E-TEC engines, carbon monoxide emissions are typically 30 to 50 percent lower that a similar 4-stroke engine and, at idle, are lower by a factor of 50 to 100 times. SERVICE Last month we began a discussion of one of the most misunderstood parts of an outboard motor: the propeller. This month we look at what effect the number of blades have. In theory, the most efficient propeller would be a single-blade design. Unfortunately, it would be extremely difficult to balance. Two-blade props were popular in the 1950's and 60's, but are seldom seen today. Three and four blade props are currently the most popular, and the more blades a prop has, the smoother it runs. Also, as the number of blades increases, the propeller's resistance through the water increases. Depending on engine set-up and boat size, this may reduce performance. In numerous instances, however, performance can be improved- particularly on high-performance rigs. Four blade props tend to keep more blade area in the water while allowing the prop to operate nearer the surface. On offshore boats, this can reduce ventilation problems when operating in rough seas. For sterndrives, it can also permit operators to use more positive trim for increased speed. On outboards, it can allow higher engine-mounting positions for reduced lower-unit drag, again resulting in better top end speed. A four-blade prop can enhance the performance of a large cruiser, too. Heavy boats need more blade area to carry the load. This can be accomplished in several ways. The first is by increasing prop diameter, but there are practical limits due to engine design. Making the blades larger on a three-blade prop or adding more blades also increases blade area. Larger, heavier boats that use "elephant ear" three-blades or four or five-blade props may suffer a slight loss in top end speed, but will correspondingly show an improvement in midrange efficiency and acceleration. They are also likely to let the boat hold plane at lower speeds and offer better handling around the dock. When changing from a three to four-blade prop the rule of thumb is to drop 1 inch in pitch. Next issue- cup, rake and pitch. HISTORICAL This month we will discuss McCulloch outboard motors. The McCulloch story is a fascinating story, worthy of a whole book, but the short version begins in 1956. The Mcculloch Corporation, which was already well known for its 2-cycle chain saws and kart engines, was looking to diversify, and decided the booming and profitable outboard motor business was the perfect venue. They acquired Scott-Atwater, and jumped right into the boat motor business. Robert McCulloch, who was a champion outboard hydroplane racer, then applied his innovation genius to the outboards, and produced many designs that were years ahead of their time. The company kept the Scott name alive until 1964, when the motors began carrying the McCulloch name. Production petered out in the late 60's with some Sears labeled McCullochs remaining until about 1971. Replacement parts remained readily available through Mcculloch until the early 80's. When the company was sold to overseas interests after Robert McCulloch's death, all outboard related items were dropped. But the question remains, why did McCulloch stop producing outboard motors? The answer is..... A BRIDGE. For more of the McCulloch story, go to the Reference page of our website. It is too long to print here. Model HP 1958 3085 3.6 3785 5 3383 7.5 3885 10 3985 16 135 22 335 22 1336 40 1536 40 1636 40 3685 40 332 60 1959 130A 3.6 137A 5 133A 7.5 138A 10 135A, 335A 25 136A, 336A, 536A 40 332A 60 1960 A3BB 3.6 A3EB 7.5 A3FB 12 A3GB,C3GB 25 A3HB,C3HB,E3HB 40 C3JB, D3JB 60 1961, 1962, 1963 Year is designated by first two digits of serial number. Scotty 3.6 Fishing Scott 7.5 Fleet Scott 14.1 Sport Scott 27.7 Royal Scott 43.7 Flying Scott 75.2 Next issue will will list the McCulloch labeled motors starting in 1964. |
Laing's Outboards Newsletter January 2005 
