Air on gas line should be tested for leaks.
Pump at least three pounds air pressure into gasoline tank.
After making sure that above rules have been observed, test compression of cylinders by turning propeller.
Be sure all compression release and priming cocks do not leak compression. If they do, replace same with a new one immediately, as this might cause premature firing.
Open priming cocks and squirt some gasoline into each.
If using Berling magnetos they should be three-quarters advanced.
If all the foregoing directions have been carefully followed, the engine is ready for starting.
In cranking engine either by starting crank, or propeller, it is essential to throw it over compression quickly.
Immediately upon starting, close compression release cocks.
When engine is running, advance magnetos.
After it has warmed up, short one magneto and then the other, to be sure both magnetos and spark-plugs are firing properly. If there is a miss, the fouled plug must be located and cleaned. There is a possibility that the jets in the carburetor are stopped up. If this is the case, do not attempt to clean same with any sharp instrument. If this is done, it might change the opening in the jets, thus spoiling the adjustment. Jets and nozzles should be blown out with air or steam.
An open intake or exhaust valve, which might have become sluggish or stuck from carbon, might cause trouble. Be sure to remedy this at once by using a little coal-oil or kerosene on same, working the valve by hand until it becomes free. We recommend using graphite on valve stems mixed with oil to guard against sticking or undue wear.
INSTALLING ROTARY AND RADIAL CYLINDER ENGINES
[Illustration: Fig. 156.--Diagram Defining Installation of Gnome "Monosoupape" Motor in Tractor Biplane. Note Necessary Piping for Fuel, Oil, and Air Lines.]
When rotary engines are installed simple steel stamping or "spiders," are attached to the fuselage to hold the fixed crank-shaft. Inasmuch as the motor projects clear of the fuselage proper there is plenty of room back of the front spider plate to install the auxiliary parts such as the oil pump, air pump and ignition magneto and also the fuel and oil containers. The diagram given at Fig. 156 shows how a Gnome "monosoupape" engine is installed on the anchorage plates and it also outlines clearly the piping necessary to convey the oil and fuel and also the air-piping needed to put pressure on both fuel and oil tanks to insure positive supply of these liquids which may be carried in tanks placed lower than the motor in some installations. The diagram given at Figs. 157 and 158 shows other mountings of Gnome engines and are self-explanatory. The simple mounting possible when the Anzani ten-cylinder radial fixed type engine is used given at Fig. 159. The front end of the fuselage is provided with a substantial pressed steel plate having members projecting from it which may be bolted to the longerons. The bolts that hold the two halves of the crank-case together project through the steel plate and hold the engine securely to the front end of the fuselage.