MOTORING NOTES

Star (Christchurch), Issue 19243, 3 December 1930, Page 15

MOTORING NOTES

r BT

MAGNETO.

IT*nr» And Tiewa. I Brooklands visitors may now enjoy i Kidget golf on a new eighteen-hole Bureo. which is played under cover on } Bet days. ■ There are 285.000 motor buses in use Hiroughout the entire world, it Is estimated. Ninety-two thousand five hunHred of these are in the United States. « « ss ■ It 1 h quite probable that, as an cxHeriment, pedestrian control lights will He erected in conjunction with the H-afflc light signals already in operation Ht Ludgate Circus, London. 38 28 25 I The Opel Motor Company, now controlled by General Motors, is said to be HVeparing to place a small car on the Berman market to sell at the equivalent If about £75. 28 38 25 I A Cardiff motorist was recently fined It Reading, first, for making an excessive noise by using an inefficient silenler, and, secondly, for not giving ludible warning of approach at cross- |°* d *' ... :* a I The Government of Ceylon has decided to appoint a committee to investilate the possibility of improving the present system of licensing motor ■.-ehicles. Such a revision is likely to benefit light cars, which, even under ■he present system, are steadily gaining ground. I A well-known firm of silencer manufacturers in England who have indented a silencer for pneumatic drills I Late that “ municipalities are doubtful ■whether ratepayers really dislike the Boise of the drills.** When one remembers the persecution suffered by motorists . . . this is really amusing. 33 33 38 Choke Troubles. I It's a common occurrence to have ■owners unable to start their cars be■eause the choke mechanism doesn’t ■work. or who have got into all kinds |r*f trouble through driving around with |the choke half out. Need for exoesIsive choking, however, is always a clue ■to simple trouble. It means’, assuming ■that the choke mechanism works pro■perly, that the mixture is much too Bean. This, however, does not mean [1 hat the adjustments have necessarily ■been tampered with. In some cases it ■may be found that the upper half of ■the' carburettor body is loose, thus ■allowing air to leak in and lean out Ithe mixture. An engine that has run ■ several thousand miles without an overlb aul f 9 liable to suffer from a diversity |ot mixture troubles. Valve guides I wear and allow air leaks; the valves [themselves are leaky and upset the | mixture, or the induction pipes may be | loose. It is practically impossible to | get a really proper mixture unless the [engine itself is in good condition. 38 35 38 The Long-# offering Carburettor. Carburettors are blamed for a great deal of trouble that is due entirely to neglect of the spark plugs. A definite and continuous skip in the engine is not needed to evidence plug trouble. Plugs, through use, fail in several ways that are not generally appreciated. The most common is a breakdown of the porcelain insulator through heat and I pressure. This causes the plug to short itself. Another form of trouble is the result of wasting away of the electrodes of the plug through the action of the spark between them. This widens the gap until the plug starts to miss. Jf an engine is operated on too rich a mixture or pumps oil the plug

points become covered with carbon and close up the gap, thereby failing to fire the mixture.

33 38 3*5 The World’s Longest Race. The most unusual and longest motor race in the world is held annually in Italy over a distance of 1000 miles. The race is organised by the Automobile Club of Brescia and, starting from the town from which the club takes its name, the course traces a rough figure through Bologna, Florence, Rome, Ancona, back through Bologna and on through Treviso. Feltre, Vicenza, Verona, and finally back to Brescia. The most unusual feature of the race is its course. The roads over which it is run are left open to ordinary traffic ■while the race is in progress. An appeal is made through the newspapers to the sporting instincts of the people to keep away from the course of their own free will. The request is complied with explicitly, and this year 140 entries, of all sorts, sizes and makes, competed over the 5000 mile route that had arbitrarily been chosen as the course. Scouring the Crankcase. It is common knowledge that when a car is new the oil in the crankcase should be drained oft and replenished by fresh lubricant after a few hundred miles. The reason for this, of course, is that however “clean” a new casting may be, there is necessarily an amount of grit and other impurities which mix with the oil When the engine is first run and forms a mild grinding paste! If the oil is drained out, most of this abrasive goes with it and after further drainings and replenishings, the, interior of the engine becomes relatively clean. The manufacturers of Rolls-Royce cars, however, employ a method which removes these impurities in the preliminary engine tests. When an engine is assembled it is placed on a test bed and is run in, gently, under its own pewer. It is not “motored” in by external power, for this reverses the stresses. Also, running of this sort is unnecessary with a Rolls, for everything is built to such limits of accuracy that the unit is perfectly free before it is fired at all. This early test is carried out for two reasons (1) to obtain a surface polish on all the working parts and (2) to scour the crankcase of all impurities.

The second purpose is achieved by the simple method of lubricating the engine from the “main,” rather than from its own crankcase. A supply tank containing hundreds of gallons of oil is connected to the engine pump and the lubricant then follows its usual course, finally draining out from the bottom of the crankcase. There is thus a continuous flow of fresh, cool oil which removes all impurities in its passage through the engine. The used oil is collected and transferred to a centrifugal “separator” verisimilar to that by which cream is separated from milk. The purified oil then goes to the main supply tank and the residue is cleaned out of the separator. This sludge has the appearance of ordinary valve grinding paste, and one has only to examine it to appreciate the damage it would do to the bearings, pistons, cylinder walls, etc., if it were left inside the crankcase! It is* interesting to note that during this preliminary test, which occupies four hours, the engine is run on coal ga;* instead of on petrol. This is convenient to use and it has the merit that it allows speeds of as low as 300 r.p.m. to be obtained. Were petrol used at such low speeds it would wash the oil from the cylinder walls, no matter how perfect the carburatfon, and would thus impair the lubrication system. [gSg]SSg§] E! !2 E® H E-g IS S H i*] ® H