MOTOR NOTES

Poverty Bay Herald, Volume LIV, Issue 16703, 21 July 1928, Page 10

MOTOR NOTES

RUTHLESS RHYMES. So popular lias motoring become among all grades of working people in America that one house magazine has civen its readers rhymed warnings "of the fate that awaits reckless drivers. The following extracts are taken from the organ mentioned: — Easy payments —no deposit; Broke his neck, not worth it, was it? At flO miles drove Edward John, The motor stopped, but Ed. kept on. Lies slumbering here one William Lake; He heard the bell, but had no brake. Speed records Johnny tried to bust; Ashes to ashes —dust to dust. This stone's over the body of Tommy Mutch At breakneck speed lie broke his clutch. At whirlwind speed drove Billy Grundy; Relations notr —his funeral's Monday. BATTERY. REMINDERS. Considering the rough usage it receives the modern car battery is a remarkably reliable component. A few years ago it was the exception rather than the rule to negotiate any long trip without a battery failure. It was not until the electrically-operated engine starter came into fairly general use that it was realised that special types of ear batteries capable of withstanding the delivery of a large output of energy were needed. The activities of different manufacturers of electrical gear have provided the car owner with a very reliable and trouble-free equipment, that will give service for five or six years, as compared with the twelve or eighteen months' service of earlier types. The motorist, 1 hough, should understand that if he is to receive maximum service from his battery there are a number of little details about which he should make himself conversant. In the first place, there Is the question of maintaining the correct level of the

electrolyte in the cells by the addition of distilled water. The plates soon deteriorate if the level is allowed to become too low, and, furthermore, the capacity of the battery suffers. Any part of the plates above the acid is inoperative from an electrical point of view. Because the level of the electrolyte in one or two cells is correct, it should not bo taken for granted that the remaining levels are right. The filling plugs of each cell should be removed when the level is being tested.

Loose connections are a source of much so-called battery trouble. Leakage of electricity often takes place through the top of the battery being allowed to become dirty. The clamps which hold the battery in position on the car should occasionally lie examined for tightness, for a battery which is loose in its mounting is subjected to road shocks of greater severity than ordinarily it would receive.

CORRECT INFLATION GIVES TYRE MILEAGE.

UNDER-INFLATION STOPPED BY CHECKING OF VALVES.

Valves,- particularly in balloon tubes, often condemned as leaky, frequently just need the caps applied or the caps tightened. In a recent check of cars parked in a street, the development department of the Goody car Tyre and Rubber Co. examined a total of 180 tyres, including spares, on over 40 cars. Of this total number, 71 tyres or 41 per cent, either had no valve caps or the caps had not been screwed down tight enough to seal the end of the valve. Of the 7.1, eighteen were leaking through the valve and could have been corrected by a very simple operation. The valve plunger which is responsible for holding the pressure within the tyre is a delicate piece of mechanism—perfect functioning of this plunger is dependent upon obtaining a perfect seating of the brass cone into the little rubber gasket in the cup which is placed at the top of the spring.

Each time a tyre is inflated, the plunger seating or seal must be broken to permit the entrance of air. In many cases while inflating a tyre, a very small particle of dirt mixed with grease or wet air may lodge upon the little rubber gasket and prevent the re-establishing of the perfect seating that had previously existed between the brass cone and the rubber gasket.

This leak may be slow and not noticeable to the car owner unless he takes the trouble to test each valve after each inflation. It is a condition, however, that does exist, and to some extent is the factor that is contributing to the necessity for more frequent reinflation. of balloon tyres. And unfortunately it is a condition that cannot be definitely controlled.

However, in terms of loss of pressure in pounds per week, the pressure loss in the balloon tube to-day is no greater than it is in the high pressure tube. In the case of high pressure tyres, the user inflates to 60 or 701bs. pressure and he has a tube of comparatively smaller volume capacity. For balloons usually 30 to 35 pounds pressure is the inflating figure and the tube is of very much greater volume capacity.

The average car owner judges the need of re-inflation by the appearance of the tyres rather than by checking the gauge.

The high pressure tyre, being small in cross section ami having been influted to a much higher pressure in the beginning, naturally runs longer, before taking on the appearance of needing more air, than the balloon tyro which started out at 30 pounds pressure. At 2") pounds, a drop of five pounds, it begins to look badly deflated.

Based on the laboratory and road tests, the opinion, is that the normal loss of pressure by diffusion with reference to time can be expressed as a percentage. For example, it can be said that the average tube leaks ten per cent, per week. This means that as the pressure, decreases due to leakage, the amopnt also decreases, but the amount is still fen per cent, of the pressure. Actual observation on the road indicates that the pressure loss ranges from two pounds to three and a half pounds per week. Present, indications are that during warm weather, the loss comes nearer the higher figures, and with lower temperatures the loss will be nearer the lower figures. These figures also vary somewhat with tyre sizes. However, if no valve cap or dust cap is used, there is no secondary airtight seal and the air pressure goes down much faster. And with balloon tyros, the necessity for keeping up the pressure is of far greater importance than formerly. WHAT MOTORING HAS TAUGHT ME. Never lo under-estimate danger. That it is impossible to judge the speed of nn oncoming car accurately. That a clear road is the only place to "get a move on." To drive all day without requiring the brake. The value of practice in the early morning. The stupidity of "showing off."