Engines Of Chip II And Sparrow [1906]

Although at the present writing the general public does not know definitely whether Chip II or Sparrow won the Gold Challenge Cup of the A.P.B.A., a comparison of the engines in both boats is of interest.

A peculiar fact in connection with these engines is that neither is regularly on sale in the open market for marine service. The Packard outfit is practically the same as used in the packard automobile, but the company is not yet quite prepared to push the sale of the engines for marine purposes. It has been rumored that Mr. Leighton contemplates putting on the market engines of the type of the engine in Chip II, but the rumor has not yet been verified.

Engine in Chip II

"The Leighton engine in Chip II, which has created so much comment among power-boat enthusiasts on account of the boat's connection with the A.P.B.A. Gold Challenge Cup races, is rather a new type in the field of marine gasolene-engine construction. The engine itself is described by the builder, Mr. Herbert J. Leighton, as follows:

"The engine consists of two power cylinders of 4-in. diameter and 10-in. stroke, with cranks opposite, and provided with exhaust ports leading through the wall of the cylinder.

"Instead of using a crankcase pump to mix and deliver the charge, a double-acting pump is attached to the shaft. This being 6½ in. diameter and has a stroke of 6 in. One end of this pump is connected to one power cylinder and the other to the other, and an automatic check valve is placed in the head of each power cylinder. A Schebler carbureter connects to a pipe leading to each end of this pump cylinder, and these pipes are provided with automatic check valves. The cranks are so spaced that in running the engine the pump draws in a charge, the piston returning about 1 in. of its stroke and compressing the charge it contains to that amount. At that time the power piston connected to this end of the pump uncovers the exhaust port and the charge passes to the power cylinder, the exhaust port of same closing at the time the pump piston reaches the limit of its delivering stroke.

"It is doubtful if at any time there is much pressure in this pump except due to the operation of the automatic valves, as in operation it could hardly be expected to fill entirely and it nears the end of its stroke much more slowly than the exhaust port of power cylinder is closed.

"The power cylinders are equipped with my regular make-and-break spark, the current for starting being supplied by Columbia dry cells, and then a Holtzer-Cabot Magneto is used.

"The water circulation is by means of two plunger pumps, one connected to each cylinder and overflowing through pieces of hose and driven by an eccentric on main shaft of engine, this eccentric also operating the spark mechanism.

"The lubrication of the crank is by splash method, and the main bearings and pump cylinder have sight feed lubricators as have the intake pipes of each power cylinder.

"The weight of the engine is about 650 pounds."

(Transcribed from The Rudder, December, 1906, p. 739. )

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