THE MOTOR WORLD.

Otago Daily Times, Issue 22025, 7 August 1933, Page 2

THE MOTOR WORLD.

By ACCELERATOR.

MECHANICS’ EXAMINATION. In addition to the list of candidates who were successful in passing the “ A ” Grade motor mechanics’ examinations, which appeared in this column on July 24, some passed with distinction and with credit. _ The following candidates passed with distinction: —Dryden Rowan, James Milne Robertson, and Francis Henry Coatsworth (all of Dunedin). The following candidates passed witn credit: —Alexander Coleman (Port Chalmers), James Gunn Leckie (Milton), Douglas Gordon Souness (Oamaruß E. 8.l M‘Donald (Dunedin). William Kean (Balclutha), Leslie Edward Lord (Dunedin), and Eric M'Sherry (Dunedin). LENDING DRIVER’S LICENSE. Through lending his driver’s license to unlicensed drivers, a young man appeared at the Magistrate’s Court at Wellington last week on two charges of doing acts for the purpose of aiding and abetting an unlicensed driver to drive a motor car. Detective-Sergeant Revell said that the defendant had lent his driver’s license to two boys who would be appearing at the Children's Court on charges of theft. When the two boys were carrying out the thefts they decided to go on a joy ride. Neither of them had a license to drive, so they borrowed one from the defendant. “Up to now,” said Mr Revell, “ the defendant has born quite a good character. He was not implicated in these thefts in any way. The defendant was fined 10s on each charge, and was ordered to pay costs amounting to £l. SMALL CARS IN SPAIN. Because labour troubles have forced increasing numbers of car owners to give up their chauffeurs there is a regular boom in Spain for low-powered English motor cars. In one Spanish city the authorities have legislated that owners must pay their chauffeurs 15 pesetas a day extra whenever they take the car beyond the municipal boundaries. Young women, dressed in clothes to tone with the coachwork of British cars, are now learning to drive in large numbers. The result is that high-powered and expensive cars are giving way to the “ baby ” variety, and English firms have obtained a strong foothold on a market hitherto practically monopolised by the United States THE SPEED LIMIT. “I do not believe that the reimposition of a general speed limit would do the slightest good. It would only divert the attention of the police from dangerous and crowded thoroughfares and corners to stretches of open road where speed is of little danger,” writes Sir A. GriffithBoscawen in the Municipal Journal. “Nor do I believe that any sort of test for drivers, which cannot ascertain whether they possess ‘road sense,’ 'would serve a useful purpose. Nor, again, do I see the use of increasing maximum penalties. The law is strong enough if only benches of magistrates and juries would use it. Minimum penalties are wanted rather than increased maximum penalties. The chief reason for the present state of affairs appears to me to be that a certain number of drivers (a small proportion of the whole number) persist in driving selfishly and recklessly. These ‘ road hogs' should be dealt with in the courts with the utmost severity.” GEAR SYSTEMS. New transmissions are making their appearance in every part of the world that is interested in motor vehicle development. Three have been announced by Victorian engineers, and several have recently gone to the market in England, while in America an entirely automatic gear box has been adopted by an American company. The latest to be tested in England are the Sensaud de Lavaud hydraulic transmission and the Parker-Caledonia infinite gear. The Autocar says that the Sensaud de Lauvaud transmission is much more than a fluid flywheel, for it gives the advantages of this component with an infinitely variable gear. From the manufacturing standpoint the de Lauvaud hydraulic transmission has j the advantages of lightness and cheapness, j Examined externally, it has the appear- ■ ance of a clutch housing. If a planetary relay is fitted—in the present stage of development this appears to be desirable to secure the highest all round efficiency— ; the whole mechanism is smaller than a ■ three-speed gear box. The turbine is self- ! contained, but an auxiliary oil tank is mounted under the bonnet, this serving : as a convenient means of maintaining the ; oil level, in the turbine, and as an overflow from the latter. Rather more than one gallon of oil is used, any ordinary type of lubricating oil being suitable, and the pressure in the turbine is nor- i mally about 251 b per square inch. I The Parker-Caledonia infinite gear is the invention of a Bedford engineer, and is described in the latest issue of Motor j Transport. Clutch action and change of gear are entirely automatic and are effected without external mechanism by the balance of engine torque and load, the changes of I ratio occurring at such intervals as to maintain the engine torque at maximum as load But between the limits of each definite step down in gearing (and three or more ratios can be provided) there is a progressive action which enables the gear to be described as infinitely variable. The automatic take-up of the clutch is ! due to the fact that it is of the hydraulic type, and the functioning of the whole transmission is based upon the fact that, a hydraulic coupling will handle only a given maximum torque, after which slip takes place. This is the actuating principle, and each gear ratio is provided with its own hydraulic clutch, so designed as to transmit the torque available from a given engine through the particular gearing associated with that clutch. But as slip commences gradually, it follows that the torque of the engine is balanced j between the clutch and gear train in i use, and the clutch ahd gear train of the next lower ratio, so that the change-over is progressive rather than sudden. The hydraulic clutches are in series, and each is coupled to the final drive through a reduction gear; thus, the greater the reduction the lighter the load on that particular clutch at any moment. Assuming each clutch to be capable of transmitting the same engine torque, 1 the 1 drive will pass through that clutch and I gear which, under that particular con- j dition of torque and load, will not permit ; slip, while the higher-geared clutches will I be slipping and the lower-geared clutches | will be driving, but over-running devices 1 are included in the gear box to meet this | condition. | SUCCESSFUL TOWING. Although mechanical breakdowns are rare in these days, every driver should know something of the gentle art of towing. First, there is the matter of the towrope. In practice you naturally have to put up with what you can get, but the best length for a tow-rope is about 25ft or a little over, so that when you have put in all the knots you can remember there may still be a distance of 20ft between the two cars. Of course, if the other car is carrying a pukka wire hawser, complete with end hooks, the knot problem won’t worry you. Having joined the two ears together for better or for worse, you must now try to think of them as one. The towing car should be looked on solely as the engine and the towed car as the brake; for if you are to avoid possible bumps or an entangled towropo, nearly all the braking should be done by the car behind. This is admittedly a counsel of perfection, for when being towed behind a bigger car than your own you cannot hope to know exactly when its driver wants to brake; but the principle should be followed out as far as possible. The driver of the towed car must take great care not to run over the rope, lest it curl ip) and wrap itself round the front axle, with possible complications to the steering. Cases have been known where the tow-rope became entangled with the mechanism, jammed the steering round to full lock and overturned the car. This over-running danger should be watched i

[ltems of news—short descriptions, of tours, the stale of the roads, etc., comment, or inquiries will be welcomed by "Accelerator.”]

with special care if a wire hawser is in use. for the stiller wire strands may make a slack hawser curl up in the air where a rope would lie flat. If the road is at all wet, or even very dusty, it is a good plan to cover as much of the front of the towed car as possible in order to keep it clean. And if the tow takes place in a town, something conspicuous —a handkerchief, coloured rag or newspaper—should be fastened to the middle of the rope. The object of this is to save the neck of the unobservant pedestrian who contemplates nipping across the road between the two cars. Finally, it is of(en a great help to arrange some method of signalling between drivers before the tow begins. The towing driver will naturally put out a warning hand when he wants the towed car to brake, but an agreed code of horn blasts is the best means of sending a message from the towed to the tower. For example, two long blasts might be taken to mean " slower,” two short blasts “quicker,” and three blasts “stop.” AUTOMATIC CLUTCH. The automatic clutch is one of the recent advances made in motor engineering. Its operation was thug described in a recent issue of Motor (England):— _ The friction clutch remains in its familiar form, together' with operating pedal, although certain parts, such as the withdrawal gear, may require strengthening. The power required to disengage the clutch can be applied by the driver’s foot, if desired, but as an alternative a vacuum servo device is interconnected, and this is coupled with the inlet pipe of the engine through a valve onerated whenever the accelerator is released. From the driver’s point of view the result is that whenever the right foot is raised from the accelerator the clutch \ pedal automatically becomes depressed, : and the disconnected engine idles. Should it stop inadvertently the suction is lost, the clutch engages, and the engine is restarted by the momentum of the. ear. Furthermore, if at any time during coasting it is desired to regain the use of the engine as a brake, an extra valve can be operated from the dash, which cuts off the suction and allows the clutch to engage. When changing gear the normal sequence of operation is followed, but the left foot has nothing to do do. Thus, for a “double-declutched” downward change one first releases the accelerator, whereupon the clutch disengages and the gear •level can at once be moved into neutral. Reopening the throttle to speed the engine then causes the clutch to engage again and to impart the necessary motion to the gears; after this a momentary release of the accelerator suffices to free the clutch while the gear lever is pushed home. It will be realised that this automatic clutch system provides many of the adj vantages which are listed in connection I with free-wheeling, and that it should 1 possess a great appeal for disabled drivers, although it does not (used alone) confer exceptional ease of gear changing. On the other hand whereas it is usually rather difficult to lock a free wheel and obtain engine braking in an emergency, this operation is simplicity itself in the case of the automatic clutch. Each system, in short, has special advantages. ADVICE ON CARBURETTORS. Carburettor trouble is practically unknown nowadays. A modern vaporiser is usually a close approach to perpetual motion. Out of sight and out of mind it automatically converts thousands of gallons of petrol into gas until the car is scrapped; and the normal motorist need not remember that there is a carburettor on his chassis. Should derangements occur (writes a prominent English carburettor _ manufacturer) these notes should assist a diagnosis and a cure. With a new car dirt in the fuel system is the only possible enemy, and dirt can hardly enter if the manufacturer has provided an efficient filter; unfortunately such filters are not yet standardised upon some cars. If dirt enters, it may completely choke one or more of the jets, and slop the car; or it may completely seal one of the fuel passages, when the engine may be difficult to start, suffer from serious misfiring, and produce little power; or the dirt may lodge under the needle valve, when fuel will drip from the float chamber, the engine will run badly, and the petrol consumption will become absurdly high. In all cases a thorough cleaning of the carburettor is the only cure. As the carburettor is a complex mechanism and may not be very accessible, it i a wise to arrest all dirt at a point short of the carburettor by fitting a good filter. Such filters can be inspected, and if necessary cleaned in a few seconds. Petrol drips from the carburettor are dangerous on certain chassis, owing to the neighbourhood of the exhaust pipe or magneto, and should be dealt witu as soon as they are noticed. With a car which has done, perhaps, 2000 miles, another form of trouble occurs very occasionally. The engine may not have been thoroughly run in at the factory. The carburettor setting which suits a stiff engine may be less than perfect for an engine which is really free. A slight readjustment by the makers' service Representative will probably give improved results in such cases. As a car ages, carburation troubles become possible through extraneous causes. The carburettor joints are disturbed when the engine is decarbonised, and it is of the first importance that these joints should be air-tight. Air leaks between carburettor and induction pipe, or between the engine and the induction pipe, upset carburation. Such joints should be clean and tight; they are usually made with soft washers, possibly smeared with gold size. The weak mixture produced by such leaks may load to “popping back ” through the carburettor, an audible and unmistakable noise, probably accompanied by little puffs of smoke or evert flame through the air intake port. Such popping back may further be due to weak mixture caused by choking of a petrol passage. (It can also be caused by certain ignition faults or by a sticking valve.) If a good filter is used water cannot enter the carburettor, but if water is allowed to enter it will cause misfiring of a violent and irregular character, as the blobs of water do not mix with the petrol, but block the passages in an intermittent and confusing fashion. In a very old engine, worn valve guides produce air leaks, which can only be cured by fitting fresh parts. Heavy petrol consumption is often due to leaks (from pipe or tank), or to drip- j ping from the carburettor (caused by dirt under the needle). ;

Difficulty in starting the engine should never be laid at the door of the carburettor. If the ignition is in perfect order, and the engine is turned sufficiently fast by the electric starter or by hand, the carburettor will always respond. But a novice may take a little time to learn the correct throttle setting for starting up. The use of low-grade spirit should be avoided, especially in cold weather. The air strangler can be used when the engine is cold, and especially in the case of large engines its use may bo necessary to keep the engine running for a brief period after starting up. These stranglers should, however, be used as little as possible. because they tend to introduce unvaporised petrol into the engine, which washes off the cylinders and pistons and dilutes the lubricating oil. In most cases the car manufacturer sets the carburettor to suit bis engine, and the owner should not tamper with its adjustment. If the owner becomes convinced for any reason that his carburettor is not perfectly set readjustment must be faced. Carburettor makers issue pamphlets containing full directions, and provide the necessary spare parts. Whenever possible, such readjustments should be entrusted to the manufacturer or one of his service agents. But if the carburettor is accessibly mounted, and the owner is prepared to take pains, the job can he done by an amateur with the aid of the instruction book. The makers’ setting is always a compromise between power and economy. Readjustment is seldom advisable unless there is a pereeptible “ flat spot ” in the throttle opening. The opening of the throttle should feel like a smooth crescendo in music; if there is a point at which the engine checks or baulks, readjustment ia desirable.

It is useless to pay a good price for a first-class lubricating oil, if excessive use of the air strangler floods the cylinders with liquid petrol, washes away the oil, and dilutes the oil in the crankcase. The air strangler should therefore be used with the strictest restraint. It should only be used wdien starting up from cold, and opened as soon as the engine consents to fire. The engine should then be coaxed to run steadily in neutral before a gear is engaged. Various low-grade petrols are on the market, and would-be economists are tempted to purchase them in the hope of saving a few shillings per annum. ’ Such inferior fuels have a disastrous effect on the engine. They render starting more difficult. Under certain conditions when the engine is cold and turning over slowly they pass into the cylinders in liquid form. This has the effect of scouring the oil off the cylinder walls. The danger of allowing this oil to be removed is obvious. Not only is the means of lubrication between piston and cylinder removed at the moment when it is most needed, i.e., at the start, when by far the greatest amount of damage due to faulty lubrication occurs, but also exhaust gas is enabled to penetrate the crankcase and take_ with it water, which may set up corrosion in the steel parts of the engine. Cheap and inferior fuels also accelerate the formation of deposits in the combustion chamber, in particular a stickiness which is apt to gum up valves and piston rings. . . , To sum up, the inexperienced owner need not anticipate any carburettor troubles whatsoever, on the following conditions: petrol pipe line; (2) use the air strangler as little as possible; (3) use none but high-grade fuels; (4) see that all induction joints are kept tight.

THE MOTOR CYCLE FIXTURES. OTAGO MOTOR - CLUB CYCLE SECTION. August 12.—Slow Hill Climb. August 15.—Monthly meeting. August 26.—-Sporting Trial. September 9.—Treasure Hunt. September 19.—Monthly meeting. CLUB NOTES. A slow hill climb is to be held next Saturday afternoon at Vauxhall. Members are requested to meet at the clubrooms at 2 p.ra. sharp. * * * The social run organised by the Motor Cycle Section of . the Otago Motor Club was very successful. Twenty-two cyclists followed the club captain (A. Crighton) to Wakari, via Kaikorai, thence through Outram, Woodside, and Berwick, to Henley, returning to Mosgiel for afternoon tea. A. Jolly (Ariel) was delayed at Wakari with engine trouble, while Bowman (A.J.S.), when passing through East Taieri, lost a nut off his clutch -and effected repairs at the local garage. After a pleasant repast and a yarn, the riders left for home, C, Bingham (Rudge) having a serious blowout in his back tyre at Saddle Hill. Forty-two members attended the “ Hardup ” musical evening in the club rooms last Tuesday. Several members of the executive were also present. The club’s orchestra, capably conducted by Mr A. Bingham, rendered popular numbers. Items were also supplied by the following;—Piano and organ duet, Messrs Belhouse and Bridger; organ solo, Mr S. Bridger; solo, Mr S. Morris; quartet— Messrs Passmore, Watts, Thorn, and Sutton; recitation, Mr Watts; recitation, Mr A. Bingham; organ solo, Mr S. Bridger; solo, Mr A. Bingham; organ solo, Mr Passmore. A parade was then held, Messrs Passmore and Watts judging the most hard-up looking member present. They picked C. Bingham and H. Ferguson as equal for first, Mr Passmore explaining that Mr Bingham, while wearing old clothes, kept them clean and had patches and torn sleeves neatly stitched. Ferguson also having the sorrowful appearance of a hard-up man. For supper, saveloys on cabbage leaves were served with bread and butter and a cup of tea.

SPARKS “ Street excavations are no joke,” says a writer. But, at least, they divert the traffic. Before going on a long journey make certain that the treads are in good condition. * « * "The modern husband plays golf while his wife goes motoring,” says a magistrate. Adam delves and Eve spins. * * * Kaye Don is contemplating an attempt upon the world’s land speed recor'd of 272 miles an hour. « & * A motor car which will be able to travel along roads and fly in the air is now being tested by Senor de la Cierya, the famous autogyro pioneer. * % % Dawdlers in cars should keep strictly to the left. A lot of humbug to traffic is being caused through incompetent drivers who Ought to be using the back streets. * * It is said that when meeting sheep on the road., if the headlights are switched on the sheep will immediately clear away out of the light, which they seem to hate, even in broad daylight, !{< >1« >1: After a puncture to which you have had to attend yourself, make absolutely certain before putting the inner tube under the cover that all foreign matter is cleared from the outside of the tube. -5Constable: I shall have to summon you miss. You’ve been doing 40 miles an hour. Young woman: You’re too late. Another policeman told me he’d do that a village or so back. >,*: sjc That type of driver who can never remember to turn on a fuel tap is now to have his omission rectified automatically, for a French concern has produced an automatic tap which turns itself on as soon as the engine starts, and politely turns itself off immediately the engine is stopped. * * Brown (who has been courteously offered a lift): I s-say, you took th-that corner at s-sixty! Y-you ought to be in a lunatic asylum! Affable stranger: How awfully clever of you to know! This is the second time I’ve escaped in the last six months! The Shell Company of New Zealand has conferred distinction on a New Zealander by the appointment of Mr R. Y, M’Dowell assistant manager for New Zealand. Mr M’Dowell has been with the company for about 10 years, and hag risen from salesman to his present position. He was territory representative in Dannevirke before coming to Christchurch as assistant general manager for Canterbury. He then became Wellington branch manager, which position he held until his new appointment. Mr W. Taylor, formerly assistant general manager, has been transferred overseas. * * * The American motoring industry has been profoundly curtailed by the prevailing world economic situation. In 1929 the United States of America produced 5,000,000 motor cars, and in 1930 production dropped to 3,500.000 vehicles. In 1931 the output of American car factories had declined by a further 1,000.000 vehicles, and in 1932 the total number of cars produced in the United States was i fewer than 1,500,000.