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time a change of speed is to be made and the clutch should not be engaged again until the gearing is positively in mesh.
Stopping the Car.—When one desires to stop the car, the first step is to release the clutch by pushing forward on the clutch pedal with the left foot and apply the foot brakes with the right foot. The gear-shift lever is brought into a neutral point and then the clutch may be engaged again if desired. On some cars the emergency brake lever and clutch-shifting mech. anism are interlocked in such a manner that the clutch is released automatically when the hand brake lever is applied. The emergency brakes of the average car are seldom used in normal operation, the main reliance of most drivers being the footoperated service brakes. When it is desired to lock the car the emergency brake lever is pulled back until the brakes are engaged and is retained in that position by a locking ratchet that engages suitable teeth cut into the brake lever segment.
Fig. 27.-Gear Shifting Method on Overland Model 75 Cars.
Steering Wheel Position. There is now but little difference of opinion regarding the placing of the steering wheel and whether it should be on the right or left side of the car. Most American motor cars, which originally were copies of foreign productions, formerly placed the wheel and control levers at the right side of the car, because they were disposed in this manner on the European cars. The road rules in Europe are
different than in this country in that a driver has to pass a vehicle going in the same direction on the right and must keep to the left of the road. This made the right hand placing of the wheel
logical and desirable. In Emergency Hand
this country, however, Brake Set
the rules of the road are that all vehicles must keep to the right and when one passes another conveyance going in the
same direction it should Fig. 28. --How to Make an Emergency Stop be passed on its left side.
With Overland Model 75 Control System.
This makes the right
hand control, which is logical and desirable in Europe, unsuitable for road laws of this country.
Conventional Control System.—To be logical the steering wheel of American cars is placed at the left side instead of the right. Most designers now follow this rule, but in order to conform as much as possible with former American practice the gear shift lever is placed in the center of the car where it can be operated by the right hand instead of at the left side. Sometimes a single hand lever is mounted in the center of the floor board and is moved in four directions. It may be rocked to the
right or left and pulled back or pushed forward in either of these positions. When the lever is straight up and down it is at the neutral point, the three forward speeds and reverse motion are obtained by rocking the lever from side to side and pushing it forward or backward as conditions demand, as shown at Fig. 27. Two pedals are provided. That at the extreme left serves to release the clutch and apply the service brake, while the one
operated by the right foot actuates the emergency brakes. When a single pedal is used for service brake application and clutch release, it is depressed about half its travel to disengage the clutch and applies the running brake from that point to the end of its radius of movement.
The instructions given for operating one type of car with selective sliding gear transmission apply just as well to all other forms, which are controlled in practically the same manner and which differ only in the arrangement of the slots in the guiding gate and the location and direction of movement of the
spark and throttle levers. Practically the same units are used in all control systems of sliding gear cars, i. e., two pedals and two hand levers are usually provided. One of the pedals invari. ably releases the clutch while the other applies the service brake. One hand lever, nearly always the one nearest the operator, is used to shift the gears, while the one that works on a notched
Fig. 30.-Sectional View of Three Speed Selective Gearset, Showing
Position of Sliding Gear Members When Control Lever is in
gment is depended upon to apply the emergency brakes. The differences in the control groups of leading American automobiles are described in detail in next chapter.
Clutch Actuation Important. The following instructions apply to all types of gasoline automobiles and may be followed to advantage by all motorists. The gear shift lever should always be placed in a neutral position when the car is stopped, whether it is left alone or attended. Gear shift levers should always move easily and the clutch pedal of all cars equipped with sliding gear transmission should be fully depressed before attempt is made to shift speeds. The clutch should always be applied gradually and as slowly as possible because too sudden or harsh engagement will produce stresses that will injure the
Fig. 31.—How the Large Sliding Gear Member is Shifted by the
Control Lever to Obtain Slow Speed.
tires or mechanism of the chassis. Never allow the engine to race or run excessively fast when shifting gears, and it is well not to undertake to change speeds with either motor or car running at high speed. When changing down, i. e., from a higher to a lower gear, allow the car to slow down until its speed is about the same as that which will be produced by the lower gear ratio desired before the clutch is again engaged after the gear lever has been shifted.
Shifting Gears Easily.If difficulty is experienced in meshing the gears, do not try and force them in mesh but hold the