THE PETROL TRAIL

Stratford Evening Post, Issue 91, 28 November 1928, Page 8

THE PETROL TRAIL

Motors and Motoring THE MIAKE IJM.Nti. * WHY IT WEARS TOO FAST. Failure of brake lining t'o wear satisfactorily is due to excessive and unnecessary generation of heat on account of dragging brakes or because of too limited breaking area,

to grease or oil on the lining, to drum scoring, and to abuse by drivers, said John N. Watrous in an address recently at 1 a meeting 'of the Society of Automative Engineers.

Many external band brakes do not conform to the shape of the drum, and when released do not springback to their original shape. Dragging of the brakes is caused also by springs which lose their temper and 'do net function in their release, parctiuiarly on transmission brakes where high temperatures and vibration influence this condition; by lack of lubrication and cleanness of the moving parts of the braking system; by rboken release springs, particularly on internal brakes; and by t ! oo fine an adjustment for clearance, ■ with no allowance for drum expansion. Rapid wear due to too limited braking area is aggravated, according to Mr Watrous, by the overloading of trucks without provision for the proper increase in braking area and, in cases in which smaller drums are used, 'due to a change in tyre equipment. Overloading also

causes changes in spring position, which may throw th e whole braking linkage out of line. Grease or oil en the lining does not necessarily affect' the actual wear factors, but' makes the brakiris action erratic, and is probably the most frequent cause necsessitating rclining of certain types of brake. Scoring of the drums has usually been traceable to the depositing of molecules of steel ion the surface of the lining, at high temperatures, during the more rapid wear of low-car-bon-steel drums, and to the abrasive action of ston e and grit embedded between the lining of the drum. It Is further influenced by too drastically burning-in new lining, before a full braking surface is 'obtained. In the opinion of Mr Watr'ous, a great percentage of scoring is started during the hist few days of use, if the lining is not properly installed and is abused by the driver before it is properly seated.

AIDS TO 3EOTOKINC.

WORTH-WHILE HINTS VALUABLE LIST. The following list of hints has been Compiled for uso of motorists in driving and caring for their cars: Active units that remain in an ungreased state break easily. A slipping clutch is a terrific waster of fuel. It is said that! a leak appears oftener in the valves than in any other place. When putting away a part for future use, place a tag on it with description. Rancid butter is an effective agent fcr removing spots from the finish, as are vaseline and kerosene. Th 0 rear axle nuts should be tightened occasionally to prevent the wearing away of the key. By using the proper size wrench on a nut the possibility of stripping the -hreads is lessened; When side curtains are put away they should be dry ar.'.l should have payor placed between them to prevent the celluloid becoming scratched. If tie horn will not bk>w and is i n good condition there is a "short" or break in th c wiring from horn to aiymeter. When the fan belt on a car is too tight it will caus e undue wear of 'bearings or bushings. An over-heated engine is caused by a leaky radiator, lack of water in the cooling system, faulty or dirty circulating system, driving long vliSJancos in first or second speed, poor L-pcration of fan, advanced spark, Or the need of oil. Sticky valves can be overcome cemporarily by running kerosene through the carburetter when the engine it hot, and putting about one pint 1 of cylinder oil in the vacuum tank. Many accidents occur because c-f failure to use the emergency brakes when the foot brakes are not sufficient to make an emergency stop. Exhaust and gasket leaks usually can be discovered by blowing tobacco smoke around the part suspected. HOW MUCH FUEL? A petrol gauge fitted en the dash-j board -which the driver can see eas-