Q. What is positive indication of binding brakes?

A. One can tell if the brakes are binding by releasing the clutch and attempting to coast down a hill without using any of the engine power. If the brakes are free the car will coast without difficulty and make good speed. If the brakes are binding to some extent they will hold the car back and reduce the speed. After a run where the brakes have not been app ied frequently the brake drums may be examined for heat. If considerable friction has been present between the brake members, the drums will be so hot that they cannot be touched with the hand. If the binding is not remedied, the friction is apt to become great enough so the brake linings or facings will be burnt or charred and will need replacement.

Q. What effect does wear in radius rod or torque rod anchorage have?

A A typical radius rod is shown at B, Fig. 301. If wear exists at the yoke at the front end where it is attached to the jack shaft or at the rear end where it is fastened to the axle, there will be considerable rattle and knocking while the vehicle is in operation. These sounds will be more in evidence on rough roads than on smooth highways because axle movement is greater. The wear commonly occurs on the bear ng pins in the radius rod end. If the portion is wh ch the pin seats is bushed the bushing may be replaced, though if the boss is of solid metal it must be drilled out, forming a large size hole, and a larger p n fitted. Most radius rods used for chain adjustment are provided with some form of turnbuckle so the rod may be lengthened or shortened to increase or reduce chain tension.

A number of points in the brake actuating mechanism where depreciation will cause rattle are shown at A, Fig. 301. If the brake shaft bearings wear, they must also be carefully refitted if any great amount of wear exists at those points. Another point to be looked after carefully are the spring shackle links and spring shackle bolts as depicted at C, Fig. 301. If these members get dry, there will be considerable squeaking, whereas if too much lost motion exists, the bolts are apt to wear through quickly or crystallize and break because of the continual hammering action and vibration they are subjected to when loose. Many mysterious rattles and squeaks while a car is in operation have been eliminated by proper attention to the various minor components comprising the brake rod, radius or torque member anchorage and spring shackle assemblies.

LESSON THIRTY-FIVE

FIXING TIRE DEFECTS

Q. Describe complete outfit for care and repair of tires.

A. The supplies and tools necessary for tire repair depend entirely upon the character of the tires the vehicle is fitted with and whether the motorist desires to make temporary or permanent repairs on the road. An important accessory that is usually included in the outfit of all cars using pneumatic tires is shown at A, Fig. 302. This a double acting tire pump of large size and is intended to be operated by hand. For temporary repairs, the complete tire outfit depicted at B will take care of almost anything that may happen from a simple puncture to a blowout. It contains patches, tire tape, tire removing and applying irons, blowout sleeve and inner liner, emery cloth, fabric, and cement. The jack illustrated at C is a powerful form adapted for all types of cars and is operated by the detachable handle B, which may also be used as a lever or pry when making tire repairs. In order to make a sure repair when patching an inner tube, many motorists carry a "cold vulcanizing" outfit in which the cement is cured by acid and which will make a much more secure patch than the plain rubber cement will. On some heavy cars, capable of considerable speed, it is almost impossible to make the average cement patch hold, and a vulcanizing set, as shown at E, Fig. 302, is a necessity.

At Fig. 303 a number of tools that may be included in the outfit to advantage, provided that the equipment does not already include a repair kit of the type shown at B, Fig. 302, are outlined. The pressure gauge is a useful indicator of the amount of pressure contained in the tires and as most makers recommend a definite amount of inflation for various sizes of tires it is well to have a

Fig. 302.-Complete Tire Repair Outfit, Enabling the Motorist to Cope with Any Form of Tire Trouble.

gauge to make sure that they are blown up to the proper point. If a casing remains on the rim for some time without having been removed, it is apt to rust or become so tightly wedged in place that it cannot be removed by the ordinary forms of tire irons. The casing release iron illustrated is adapted to force the bead of a heavy clincher tire out of the rim flanges without requiring the expenditure of much power. The four tire irons are supplied to remove and apply clincher casings and are useful adjuncts to the casing release iron. The 4 in 1 valve tool is very handy when it is needed as sometimes the valve may be damaged when removing or inserting an inner tube, especially if the valve stem is carelessly struck with the

tire iron to remove it. If the threads are damaged on the outside of the valve stem so the valve cap will not go on, the threads may be recut by using a small die in the center of the tool. If the thread is damaged on the inside of the valve stem it may be cleared out by using the tap projecting from one end of the die and serving as a handle by which it may be turned. The other projecting arm is a key to unscrew the valve inside, while the short projection is a face reamer or cutter for removing any burr that will prevent the valve cap from seating securely on the stem. The thermometer shown is the standard form used with all types of small portable vulcanizers. It is not necessary, unless a vulcanizer is carried as part of the equipment.

Fig. 303.-Useful Accessories that Facilitate Maintenance and Repair of Tires.

Other parts that may be carried to advantage are shown at Fig. 304. Many motorists find that attempting to patch an inner tube on the road consumes too much time so spare tubes are carried in a suitable case and are inserted in place of the damaged member without any more delay than is necessary for replacing one tube with another. The injured tubes may be repaired at leisure, and carried as a spare when restored to the proper condition. The valve inside, valve cap, and valve cap washer of the standard shrader valve are also shown. It is well to always have at least a half dozen of the valve insides and three or four of the caps and