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the driver in locating the speed shifter. Most cars that 'nave the selective gate have the various speeds clearly indicated by means of lettering and numbers. The letter R indicates the position for reverse motion of the car. The numeral 1 indicates low speed; 2 shows the proper lever placing for intermediate speeds, while 3 indicates the higher speed or direct drive position. Cars using more than three speeds have an additional slot in the quadrant used only for reverse. The “cane” shift is used only with cars having three speeds forward and a reverse. • It is not difficult to discover the proper lever placing to obtain the different speeds if these are not indicated. After the engine is started, if the clutch is released the gear lever may be placed in any position the driver desires. The engine is speeded up a little and the clutch is engaged very gradually. If the car starts smoothly and without appreciably diminishing the engine speed it is evident that the low speed gear has been engaged. The other extreme position of the lever on that side of the quadrant is practically always the reverse. Similarly if when the clutch was engaged the car started to go backward, the fact that the reverse gears had been meshed would be selfevident. If when the clutch is engaged the car starts forward but almost stalls the motor, the change speed lever has been put into the intermediate gear position. If the engine stops or "stalls” when the clutch is engaged, the gear shift lever has been put in the high speed or direct drive.

In most cars the low speed and high speed are obtained by moving the lever in the same direction, though of course at different sides of the quadrant, or by rocking it to opposite sides of the center. The reverse and intermediate speed positions are usually on the same line, the reverse speed position being on the same side of the car as the slow speed while the intermediate is invariably on the same side as the high speed. When experi. menting in this way it is well to have one foot ready for the brake and one on the clutch, so that it may be released imme. diately if the proper speed ratio has not been engaged. The reason why the low speed and reverse are obtained at one side of the quadrant while the intermediate and high speeds are

obtained at the other is because as gear boxes are ordinarily constructed the shifting member that gives the low and reverse speed is shifted by one fork while that that moves to give the intermediate or high speed is operated by another shifting fork. The various movements of the change speed gear members neces. sary to obtain the various speed ratios are very clearly shown in Figs. 30 to 34, inclusive.

GENERAL CONTROL HINTS Buick.—The driver's compartment of the Buick Light Six is clearly shown at Fig. 36. The position of the various control elements are clearly indicated and can be readily identified. Before starting the Buick motor see that the ball top control lever stands in a neutral position where it is free to move sideways. The spark and throttle levers on the steering wheel are moved about one third of the way down on the sector. The switchboard is unlocked so the keys can be shifted and the button marked “Ign.” is pulled out. The air regulator or choke button is pulled out and starting pedal is pressed with the foot. This starts the electric motor and turns the engine crankshaft over. If motor does not start in a half minute, release the starting pedal and examine the various control members to see if they are properly set. Then depress the starting pedal again. In ordinary weather the motor should start readily, but in very cold weather the engine is apt to start hard, especially if the car has been standing some days. As soon as the motor starts, push the air regulator button, which is at the extreme left of the cowl board, half way in and leave it in that position until the motor is thoroughly warmed up. When the motor has been run for some minutes, the air regulator button may be pushed all the way in. It is stated that the motor should not be run for any length of time with the air regulator button pulled clear out because this produces an excessively rich mixture. Pull the spark lever down as far as it will go on the sector, as the automatic spark advance feature of the igniter will take care of spark timing for all ordinary driving. Close the throttle lever on the steering wheel until the motor runs slowly and yet

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without misfiring. The foot accelerator can be used to control the speed of the motor.

Now that the motor has been started it is possible to set the car in motion. The first step is to release the emergency brake lever by pulling it back enough so that the thumb button on top can be depressed, this unlocking the ratchet, and then push the lever as far forward as it will go. Place the left foot on the clutch pedal, press it down firmly and keep it in this position, then with the right hand move the control lever over to the right and then pull it back. This puts the gears in the low speed position. Press lightly on the accelerator pedal to increase the speed of the motor and let the clutch in gradually by releasing the pressure of the left foot on the clutch pedal. Increase the speed of the motor until the car gains headway. When the car has acquired sufficient momentum, disengage the clutch again, and let up on the accelerator pedal. With the right hand shift the control lever forward to the neutral position, then over to the left of the car and then forward again as far as it will go. This gives the intermediate speed. The next step is to shift into the high speed or direct drive. This is done by depressing the clutch pedal and pulling the change speed gear lever as far back as it will go. The speed of the car can be controlled entirely by the use of the accelerator pedal. If it had been desired to obtain reverse speed, instead of having pulled the gear shift lever back after it had been shifted over to the right it would have been pushed forward. When a car has been moving forward, it is always necessary to bring the car to a full stop before putting the change speed lever in the reverse position.

Cadillac Eight.—The control system elements of the Cadillac “Type 53,” as well as the instruments on the cowl board, are clearly outlined at Fig. 37. Before starting the engine the transmission control lever should be in neutral position and the hand brake applied. Note the pressure of air in the gasoline tank, which is indicated by an air pressure gage carried on the dash. If the pressure is less than one pound, it should be increased to that pressure by means of a hand operated air pump which

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Fig. 37.—Control Group of the Cadillac Eight Cylinder Automobile.

is placed alongside of the speedometer. After the engine is started, pressure is automatically maintained by a power pump driven from the engine. Place the spark lever at the right of the sector and the throttle lever about two inches from the extreme left. Move the ignition switch lever down to switch on the ignition. The ignition and lighting switch is carried at the extreme left of the dash. Depress the starting button with the foot, to turn over the engine. If the engine has been standing for some time in warm weather, and practically always in cold weather, pull up the auxiliary air valve lever which is carried on the steering column brake in order to choke the air passage to insure positive start before the starting button is pushed down. As soon as the engine fires and runs under its own power the pressure should be released from the starting button. The auxiliary air valve lever is pushed down half way as soon as the engine is started, and all the way down as soon as the engine is warm enough to permit doing so.

Whenever the engine is cranked by hand, the spark lever should always be placed at the extreme left of the sector in order to retard the spark. - Never press in the starter button while the engine is running. Before starting the car the hand lever should be released by pushing it to its extreme forward position. The same rule for speeding up the engine, declutching before shifting the gear lever, letting in the clutch gradually and obtaining sufficient momentum before shifting from higher to lower gears, previously given, should be followed in all cases. This car also employs the “cane” shift, and when the transmission control lever is in neutral it is standing approximately vertical and can be easily rocked from side to side. To obtain low speed the lever is moved as far as possible over to the left and then pulled back as far as it will go. If the lever is moved to the left and pushed forward it will engage the reverse speed. To obtain the intermediate, the lever is pushed over to the right from the neutral position and as far forward as it will go. To obtain high speed the lever is rocked to the right and pulled back.

Chalmers Six.—The driver's compartment of this car, with

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