1905 New York Motor Boat Show

Motor Boat Engines at the Sportsmen's Show

At the eleventh annual Sportsmen's Show, now being held in Madison Square Garden, New York, the exhibit of motor boats and their engines, together with a large oval display tank in which the boats are shown in action, occupies the entire main floor. Although there is no great change in the construction of the boats themselves, there is a decided increase in the size of the gasoline engines used on some of the larger ones for the purpose of developing high speed, and the number of cylinders used is as high as six or eight.

The accompanying illustrations show several of the noteworthy engines on exhibition. The 250-horse-power, eight cylinder Craig engine used in the Onontio when she made her record nautical mile in 2 minutes 26 seconds (28.42 statute miles per hour) last October is the largest engine at the show. The large inlet and exhaust pipes used on this engine are noticeable in the photograph. They are 3 and 4 inches in diameter respectively.

The cylinders have a 7¾-inch bore and a 9-inch stroke, and, their heads contain twin inlet and exhaust valves mechanically operated by bell cranks worked from a single cam shaft on one side. The compression used is 80 pounds, and the speed of the engine 850 R.P.M.. A three-bladed reversible propeller was used with it on the Onontio. The cylinders are mounted on nickel-steel stanchions, the cranks being entirely exposed. the bearings and cranks are lubricated by wick oilers. The crankshafts, of which there are two coupled together at the center, are 2 7/8-inches in diameter. They are of nickel-steel, hollow-bored. The bedplate, bell cranks that operate the valves, and a number of other smaller parts are made of manganese bronze.

The total weight of the engine is 3,520 pounds. Variable make-and-break igniters are used on this engine, the current being supplied by two magnetos driven by bevel gears. The two four-cylinder engines of which it is composed are thus independent even to their ignition current supply. Separate carbureters supply each also.

Another engine built on somewhat the same lines as the Craig is the new 100-horse-power, six-cylinder Standard, which has 8 x 10 cylinders and develops its power at 300 R.P.M. This engine has its valves in a valve chamber beside the cylinder. The inlet valve is automatic, or suction-operated, and is provided with a small piston on its valve stem. This piston (which is fitted with one piston ring) works in a closed cylinder having but two or three small air holes, through which the air can escape. Thus it forms an air dash pot and keeps the valve from seating too heavily.

An extra set of cams permits of running backward. Three of the cylinders are fitted with auxiliary valves for letting in compressed air for starting and reversing purposes. A special cam opens the exhaust valve during every up-stroke of the pistons, and air is admitted during every down-stroke, so that the tree cylinders form a single-acting compressed air motor under those conditions. As soon as the other three cylinders begin to fire, the air is shut off and the whole engine is run on gasoline. Sufficient air is carried, at a pressure of .75 to 100 pounds per square inch, to run the engine two or three minutes this way alone. The air is compressed by an air pump driven by an eccentric on the crankshaft. The starting and reversing feature makes a clutch and reverse gear unnecessary, as the engine can be started and reversed under load.

The 150-horse-power Simplex engine of the Challenger, which boat covered a mile recently in Florida at the rate of 29½ miles an hour, consists of eight cylinders cast in pairs and bolted to a single aluminium crank case. The crankshaft is a steel forging of generous size. The bore and stroke of the cylinders are 8½ and 6 3/4 inches respectively, and the compression used is 95 pounds. The motor develops its full power at 800 R.P.M. it is fitted with a jump spark ignition from storage batteries and two spark coils, the secondary current being distributed to the various spark plugs by means of two high-tension distributors. The oil is kept at a certain level in the eight compartments of the crank case by means of a special oil pump. A small scoop on each crankpin box dips into the oil and raises a small quantity of oil at every revolution, pouring it into a trough in the upper part of the case, which directs it to the bearings. The sight-feed oilers at the top of the engine also oil the bearings and cylinders. a single automatic carbureter supplies all eight cylinders. in this carbureter the main air passage is very small, and the auxilliary air enters through specially-shaped passages determined by experiment and so shaped that the rate of admission of the air varies with the speed of the motor. The motor has all the improvements suggested by a large automobile experience, such as the ends of the exhaust valve springs being passed through holes in the valve stems instead of being secured by a washer and pin, for example. it is set at an angle of 5 deg. in a boat, but the special oiling system assures a liberal supply of oil to all bearings, without too much oil at the lower end and consequent fouling of the spark plugs.

The two six-cylinder engines shown by the Gas Engine and Power Company, of this city, were two of the finest and best-finished engines at the show. This company's product, both motor boats and automobiles, is sold under the name "Speedway." Two types of four-cycle motors, besides several small two-cycle engines, are manufactured by it. the most interesting engine on exhibition is the six-cylinder, four-cycle motor with elliptical brass water jackets. The inlet and exhaust pipes pass up within the jackets, and the only pipe or piece of machinery exposed besides the cylinder is the rod that operates the rocker on top for opening the exhaust valve. The inlet valves are automatic, and, with the exhaust valves and spark plugs, are located in the head. The contact maker is on a vertical shaft at the rear end of the motor. Individual spark coils with tremblers are used. The cylinders are mounted upon steel stanchions instead of on the crank case. The bore and stroke are both 6 inches, and the motor develops 60 horse-power at 900 R.P.M. The other four-cylinder motor is of the standard automobile type, with individual, integrally-cast cylinders bolted to the crank case, with mechanically-operated inlet and exhaust valves, single carbureter, jump-spark ignition, etc. It has a 4½-inch bore by 5-inch stroke and develops 42 horse-power at 900 R.P.M. The company also builds a 7 horse-power, two-cylinder, a 10½ and a 21 horse-power three-cylinder, and 14, 28 and 60-horse-power, four-cylinder motor of this type, as well as a 90-horse-power six-cylinder. A 3-horse-power single-cylinder and a 6-horse-power double-cylinder two-cycle engine are also manufactured.

One of the novel motor boats on exhibition was shown by the Electric Launch Company, of Bayonne, N.J. The motor of this boat was placed forward of the cockpit in the bow of the boat, and the cockpit contained four small seats with aluminium backs, such as are seen on automobile racers. The steersman is intended to sit directly back of the motor, and the whole layout is much the same as on an automobile. The Panhard boat was constructed on similar lines, although the motor in this instance was not placed so far forward. The design does not appear to be as good as the usual one, in which the motor is placed in the center of the boat; for with the motor in the bow, the boat is liable to be top-heavy in a seaway, and the motor also is difficult to get at for adjustments.

(Transcribed from Scientific American, March 4, 1905, pp.186-187 )

[Thanks to Greg Calkins for help in preparing this page]