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ing screws in order to lock all parts firmly together. Two of these clamping screws are in the small bevel sectors while the others are in the levers, one at the bottom of the steering column, the other at the top. There may be a tendency at times for the entire toothed segment to turn with the steering wheel which causes the engine to race or which shuts it off altogether when turning a corner. This annoying condition is due to looseness of the sector supporting tube in the anchorage plate at the bottom of the steering column. If difficulty is experienced in keeping this tube tight, the trouble is due to deposits of rust between the sector supporting tube and the interior of the hollow steering column. The only remedy is to remove the sector retaining tube from the interior of the steering column and remove all rust deposits and coat the parts liberally with lubricant before reassembling.

The control levers at the top of the steering column are usually of the form at Fig. 360, A, though in some cases the construction shown at B is used. After the car has been used for a time the fine teeth on the sector may become burred over and the ratchet plungers may be rounded by constant friction with the teeth so the levers no longer stay in the places where they are set. The remedy for this condition is obvious. The teeth in the sector must be recut with a fine, three cornered file and the ends of the ratchet plungers must be repointed by grinding and the springs keeping them pressed against the sector should be strengthened by lengthening. When the friction block arrangement as shown at Fig. 360, B, is employed, any tendency to slip may be easily remedied by tightening up the spring tension adjusting nuts shown. The increase in spring strength augments the friction between the friction block and the side of the casing and serves to retard too free movement of the control lever.

A complete steering gear assembly with all parts clearly indicated is shown at Fig. 361. This shows the various points where back lash may exist and the resulting lost motion produce erratic steering. Taking these up in order, we have first the bolts supporting the wheel spindles in the yokes at the end of the axle, and the bushings in the wheel spindle itself. Next we have the pins and rod ends at the end of the tie rod, then the connections at each

end of the drag link. The point where the steering arm fastens to the steering gear should also be inspected to make sure that the arm is firmly clamped to its actuating shaft. On practically all cars, removable bushings are provided in the steering spindle which may be readily removed and replaced with new when worn. The ends of the tie rod have the bolts in them a tight fit and usually screw through the lower portion of the rod end. This means that

[graphic][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed]

Fig. 361.–Showing Important Linkage of the Steering System.

the wear will come on the bushing in the steering arm that extends from the spindle instead of in the rod end.

The various steering gear parts that demand inspection are grouped at Fig. 362. The section at A shows a worm and worm sector steering gear with the upper half of the gear case removed to expose the gearing. This form is subject to the same trouble that the full worm gear and worm arrangement previously described is, but in event of wear of the sector teeth it is not possible to turn this over and obtain a new set of bearing surfaces. Practi. cally the only remedy when this construction is followed, is to replace the sector with a new one. Of course, if the lost motion is due to poor adjustment, the usual eccentric bushing method of bringing the teeth into more intimate contact may be used. The arrangement of the rod ends used on the drag link and designed to operate in connection with the balls usually provided at the end of the steering arm is shown at B. As will be apparent, the ball rests between two plugs having semi-spherical depressions that act as a ball seat. One of these plugs is pressed against the ball by a substantial coil spring, while the other adjusting plug is brought in contact with the ball with a threaded adjusting plug. As the ball can only be introduced in the socket when the adjusting plug is out, which permits the small section of the steering arm to fit the slot, it will be apparent that even if this joint should loosen that it would be practically impossible for the ball to come out. In event of lost motion being manifested this may be easily taken up by loosening the clamp bolt or removing a split pin lock sometimes provided and screwing in the adjusting plug until all lost motion is eliminated.

The usual steering knuckle assembly is shown at Fig. 362, C. It will be observed that the bolt acting as a bearing for the steering knuckle and passing through the top and bottom of the steering yoke is provided with a grease cup at the upper part in order that the joint may be kept thoroughly lubricated. After the front wheel has been properly adjusted, if it is desired to find if there is any looseness in the steering knuckle, the wheel should be grasped by opposite spokes, one at the top, the other at the bottom and with the leverage thus provided endeavor to shake the knuckle on its supporting bolt. If there is any lost motion the bolt should be removed and its bearing surface examined. If it has been cut into or is reduced in diameter at the bearing points a new bolt should be provided. If the bushings in the steering knuckle are worn they should be driven out and new ones supplied.

Some inexperienced repairmen and many motorists are inclined to believe when they first see a “dished” front wheel that the front axle has sprung and that the construction is faulty. There is a very good reason for tilting the wheel as shown at Fig. 362, D. This

[graphic]

CLAMP
BOLT
STEERING

Acva

DJUSTING
ARM

NUT
9 A

ROLLER BEARING POINT OF

WHEEL

CENTER LINE OF

-SPINDLE BOLT
INNER RACEROLL AND

12%
SEPERATOR

ASSEMBLIES
Fig. 362.-Showing Parts of Automobile Steering System that Demand Inspection when Overhauling.

is to obtain ease in steering and the usual angle of inclination is about three degrees. Without going into an involved explanation of the reason for doing this it may be stated that it is a mechanical principle that the nearer the center of the spindle bolt and the pivot point of the wheel are to an alignment, the easier the car will steer. If it were possible to bring the center of that part of the tire which is upon the ground to a point exactly under the joint of the steering knuckle the arrangement would be ideal. To secure this alignment or to get as near to it as is practical with the accepted Elliot steering knuckle construction, it is customary to tilt the wheel. In the case of the Ford car, a plumb line dropped through the spindle bolt would strike the ground about two inches from the pivot point where the wheel tire rests on the ground. The diagram makes this point clear. It is customary to find the front wheels of large cars dished in the same manner so this point should not be confused with lack of alignment in a horizontal plane which will interfere with correct steering and result in rapid tire wear.

Testing Wheel Alignment.-A splendid opportunity is present during the overhauling period for aligning the wheels and axles which should be done to make sure that they have not moved out of their correct position. But little apparatus is needed to make these trials, the outfit consisting of two chairs, two heavy pieces of wood, and two lengths of stout cord. One chair is placed at the rear of the chassis, the other at the front as indicated at Fig. 363. The chairs are located as near as possible to the center line of the machine and after the cords have been adjusted the chairs are spread apart enough to tighten the cords. In order to prevent movement of the chairs when they have been properly placed they may be weighted down with iron or steel parts. The important thing to do is to have the cords parallel to the frame side member and to have the member on the right just the same distance away from the right hand frame rail as the left hand cord is from the left hand frame rail. A common defect of alignment of the front wheels is shown at A. In this case the tie bar is too short and the wheels are nearer together at the back than they are at the front. The opposite to this condition is shown at B, in which case the tie

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