MOTORING WORLD.

Manawatu Standard, Volume LI, Issue 111, 11 April 1931, Page 14

MOTORING WORLD.

It is estimated that there are now 25,279 cars in use in Poland, as compared with only 21,692 a year ago.

At least two inches of play or loose movement on the clutch pedal should be allowed when adjusting a clutch.

In the Australian Commonwealth postal services automobiles carry mails over 1854 routes and cover a distance of more than 8,750,000 miles every year.

The police of Detroit are waging a war against smoking exhausts, owing to the fact that other drivers are term porarily blinded by clouds of exhaust smoke.

Germany now has 45,000 petrol filling stations, or one for every 12.2 automobiles, while America has 310,000, or one for 70.4 cars.

The French Chamber is giving consideration to a scheme to reduce by half the tax on motor cars used by farmers, doctors, lawyers and other professional men when the vehicles are used in the course of their work. Constant and regular attention to the greasing of all nipples, shackle bolts and other bearings should be a fetish with every motorist. Many accidents can be traced to carelessness in this respect. Clean out all carburettor jets by removing jet plugs, and never allow petrol unions of joints of any kind to show the slightest moisture from petrol leakage. This will not only minimise the risk of fire, but will assist in obtaining extra mileage. After adjusting brakes, jack up front and rear axles to make sure that all the wheels run freely. The rear wheel brakes should be adjusted to come into operation slightly before the front wheels, thus making for safety in emergency.

British “baby” motor-cars are very popular on the Continent, more than 11,000 having been exported to France and 14,000 to Germany. In America, where they arc made under license, orders have been received for about 200,000 to date. The Maharajah Rana Bahadur of Jhalawar has placed in England an order for £IO,OOO worth of cars for use in India. Among them was a car which he drove round Brooklands track as part of his tests. He also included an 8 li.p. fire tender. According to a recent report from Paris an important contract lias been arranged between a French concern and the Soviet Government for the exclusive importation into France of 300,000 tons of Russian petrol yearly, while the French company is said to be in negotiation with the Soviet for the importation of Russian crude oil to be refined in France. After your car has covered a few thousand miles, smoke may issue from the breather-tube or the oil-filler pipe —a sign generally that engine gases are leaking back past the rings into the crankcase. In which case the rings need attention, or the pistons are “sloppy.” This condition is often misleading, for the owner may think that the oil is too thin. Remember, thick oil cannot replace wear. Drain the engine sump every 1000 miles. If the car is fitted with an oil strainer, clean this every 5000 miles.There is nothing to be gained by creating a long distance record on one fill of lubricating oil. Good oil and plenty of it is the cheapest way Of reducing the repair bill. This applies also to the gear box and rear axle. Guard against over filling; all levels are stipulated by the makers of the car and should be rigidly observed. One of the leading American brakelining manufacturers has adopted a new idea in motor insurance, under which every motorist who lias his brakes relined with the firm’s material is entitled to a £2O accident policy, valid for one year. To keep the insurance in force it is necessary for the motorist to have his brakes inspected every thirty days at one of the company’s authorised service stations in the United States and Canada.

Recently interest was aroused by the construction in England of a special streamlined saloon car with the engine at the rear, which, despite an unfavourable power weight ratio, attained a remarkable speed. Now another ca,r on similar lines is being made in Paris to the order of a well-known Egyptian sportsman, which, judging by a printed illustration, will be of attractive appearance. It will have g larger engine than the British production, a 5000c.c V eight-cylinder with gearbox and differential in unit with the engine, the differential being between the engine and gearbox. Hypoid gears are fitted. The car has a wheelbase of 12 feet 3 inches, the body space being 7ft. 6in. by 4ft. 6in. from the pedals to the back of the rear seat. The passengers are carried between the axles, and between them and the engine is a baggage and spare wheels compartment running the full width of the body, with a door on each side equal in height to that of the two main doors. The radiator is set in the sloping roof, immediately above the engine, and forms portion of the streamlining. The tools and battery are contained in two boxes let into the chassis, and instead of running boards a bumper bar is fitted below the doors on each side of the body.

MINIMISING WEAR

LUBRICATION PROBLEMS,

Motorists who consider that the wear' and tear in some modern engines is excessive as compared with the long life of the old slower running types of large-boro four cylinders will find much to interest them in the views of some eminent British engineers on lubrication.

It is pointed out that while the oil in use does not lose its basic composition, it may become so contaminated that its lubricating value is seriously impaired. The first function of lubrication is to reduce the friction offered by the movement of one mechanical part over another. The majority of modern motor bearings operate under flood lubrication conditions, with an unbroken film of oil between them preventing metallic contact. Rupture of this film causes seizure, or partial welding of the surfaces in contact. Internal friction between the molecules of the oil is expressed by viscosity of the oil. It is probable that the piston and possibly the big end bearing operate under the severest conditions as regards lubrication, and suffer the most starvation of oil. Mr Ricardo compares the movement of a mechanical part in its bearing to a flat-bottomed punt beiim drawn along a shallow stream, the bed of winch is composed of slime-covercd gravel. When the punt is floating freely, a layer of fluid or lubricant separates the bottom of the punt from the bed of the creek, corresponding to an ideally lubricated bearing. When the bottom of the punt drags on the gravel, however, the slime acts as a partial lubricant, equivalent to starved mechanical oiling. RUSTING TROUBLE. If a motor manufacturer arranges for adequate lubrication, a high oil consumption and smoky exhaust are probable. Cutting down the oil supply brings the risk of undue wear in the cylinder bore. The adoption of new hard cylinder materials to obviate this danger, and the fitting of upper cylinder lubricators is a remedy, which, however, is accompanied by the fact that a seizure with these materials is more serious than with standard cast iron. Then, when an engine is started from cold after standing, there is practically no oil in the bores, and rust may have formed. Rusting trouble is the serious part of dilution. Although petrol is a reasonably good lubricant, it evaporates from the hot walls of the engine, and leaves them dry. A mirror-like surface to a cylinder bore does not invariably indicate perfect lubrication. Lubrication also exercises an important function in cooling engine parts. The piston takes up a great deal of the heat of the explosion, and dissipates it through the rings and the oil. This heat is considerable in modern high-speed engines, and big end ,tempernture is fast becoming a limiting factor in design. It necessitates increasingly high oil pressures, as the big end fluctuates between flooded and partial lubrication. Under conditions of arduous loading, the oil in the sump may reach a temperature of 200 degrees Fahrenheit, and it enters the main bearings at this temperature, to experience a further rise of perhaps 50 to 60 degrees. It is claimed that in the big ends,. the oil temperature will rise to as much as 350 degrees, at which the important feature of viscosity is very low, and the film of oil dangerously thin. The white metal lining of the bearings at this temperature is very near the plastic point. It is possible also that, owing to the thinness of the oil film at this temperature, abrasive narticles which would normally b-e innocuous span the bearing and cause seizure. In order to keep down this heat, lubrication systems are now in use which force as much as eight gallons of oil a minute through the crankshaft hearings. Larger clearances are also being provided in hearings to permit of thicker films of oil penetrating between them. COMPRESSED AIR. MODEL AERIAL ENGINE. After a lifetime of experiment and investigation, following on a long period of similar work by his father, Mr E. C. Preston, of Aslifield, N.S.W., lias developed a motor driven by compressed air, in which he lias great confidence, especially for use in aeroplanes (states the Sydney Morning Herald). He is now completing at Ins home in Aslifield the working model of the machine. At the first superficial examination •f this machine, the criticism of several who had previously seen it that it was another attempt to produce perpetual motion seems to be justified, but the inventor’s explanation of its characteristics shows that he is really practical in his ideas. Essentially the machine consists of an inner rotary motor with four cylinders radially opposed in pairs, the outer portion being a driving wheel to which power is transmitted in a novel and ingenious manner. The centre of the motor is carried on a hollow shaft with which, Mr Preston states, it is not in contact while working and which contains the apparatus for applying the compressed air to the pistons within the cylinders. . . . .. When the compressed air is admitted to the cylinders it forces the pistons outwards, and they in turn operate through connecting rods on to long curved members connected at one end with the inner edge of the circular peripherv of the motor. These members resemble brake shoes in appearance and are hinged to permit them to take up driving positions when the air pressure is applied. By 'an ingenious system of springs and levers, each piston is induced to exert a continuous pull and push in the same direction on opposite sides of the wheel, the power thus being constantly transmitted to the outer edge and taken up as rotary motion by the outer driving band. Speed can he regulated by varying the air pressure on the base of the pistons. Tested with an extemporised worm drive, the spiral portion of a large auger being pressed into service ns the worm and a Avooden worm wheel being constructed to fit it, Mr Preston states that he has already attained satisfactory results, showing that the motor will perform efficiently under load. Mr Preston’s father, the later Mr J. B. Preston, of Forbes, and later of Petersham, was also keenly interested in aviation, and was in many respects a man with ideas in advance of his time. He also laboured hard on the invention of an aeroplane; and in this lie had some success as far as the machine was concerned; he was obstructed by the lack of a powerful and light engine to propel it. It was with the idea of providing mechanical propulsion for his aeroplane that Mr J. B. Preston devoted his attention to the pneumatic motor, and in 1890 he had advance! its design to such an extent that he entered into an agreement with a leading firm of engineers in Sydney to construct the machine in tlieir work, they extending a certain amount of financial support. When Mr J. B. Preston died, Mr E. O. Preston carried on the experiments in connection with the motor, but says that it has developed on altogether dif-

ferent lines from those originally planned by his father. In response to criticisms that his motor his attempting to upset the mechanical theory that only as much power or less can be obtained from a machine as the motive effort imparts to it, he urges that there is tremendous power in compressed air, and quotes the analogy of a man of ordinary physical strength who can raise an immense weight with little effort with the assistance of a winch, rope, and pulley. His motor is ingenious, and it will be interesting to see how it really performs under load when complete.

IMPORTANT JUDGMENT. An important judgment by Judge Heydon, in an English county court, is of special interest to motorists, as it lias a bearing upon the neoessity of using motor tyres that have efficient treads. The case arose out of an accident in which a car skidded, causing a collision. The defence was that the skid was unavoidable, but the Judge held a definite opinion on the subject, and stated that the defence must satisfy him that no blame a-ttached to the driver of the skidding car. The purpose of patterns on motor tyres was to minimise or avoid skidding, which would he unavoidable with smooth tyres. As the defendant was driving on tyres that had worn smooth, which constituted a defect, the defence failed, and the plea that the accident was unavoidable was not accepted. This decision is an important and far reaching one, and points to the danger of motor, ists using worn-out tyres that constitute a risk when driving on slippery roads. Tyres to-day give wonderful mileage before they wear to a dangerou.s condition, and, considering that they cost considerably less now than in pre-war days, there is no justification for taking undue risks in this connection. OPENING DOORS BY RADIO. Opening and closing the doors of the private garage by radio is the idea in automotive accessories. The operation is performed by a specialised dashboard radio set which transmits a signal that automatically opens the garage doors. The device is said to bo simplicity itself—a pull on a knob on the instrument board of the car and the garage doors open; another pull and they close. A tiny sending set is installed in the car, the receiving set mounted within the garage, and a door operating mechanism, also within the garage. It is also possible to code the signals sent by the transmitter! Thus a car carries its own key to its garage. The transmitter, which is installed in the car, consists of three main parts—the timer, the spark coil unit, and the transmitting antenna. The. tinier which governs the sending of the impulses is encased in a small box and mounted under the instrument board by means of a clamp. The coil unit, clamped to the main frame, furnishes the high frequency current necessary for broadcasting. To the observer there is only one part of the mechanism visible —that is the small knob which protrudes from beneath tho instrument board, and this is the only part- that the driver is concerned with in working the device. Power for the transmitter is drawn from the ear battery, and, since the current is no greater than required for parking lights, the consumption is said to he very small. The receiver unit is contained in a box about a foot square which is mounted on the wall inside the garage. Connected to it is the . receiving antenna, which consists of a wire buried in the driveway. Radio impulses sent out from the car are thus transferred to the receiver. Upon receiving the correct series of impulses, the receiver closes a contact which starts the door-opener, a motor driven mechanism mounted above and behind the garage door. AVlien the doors are closed they lock automatically and. in ease power is shut off, it is possible to operate the doors manually. The finishing touch to this interesting device is enjoyed at night. When the car lights are burning the signal from the car -not only causes the doors to open, but turns on the garage lights as well. The lights and doors can be operated independently of each other and the radio control. VALUE OF MOTOR RACING. Throughout the world the success of Captain Malcolm Campbell—England’s I famous racing motorist—in increasing the world’s fastest land speed to 245.v36 ni.p.li., lias stirred the imagination of many millions of people. All motorists will appreciate wliat a stupendous undertaking is involved in designing and building a car for such colossal speeds. It took nine months to make the “Bine Bird II.,” many thousands of pounds being spent on its production. Fortunately, all calculations were correct, and to-day Campbell is the proud holder of the world’s land speed blue riband—an honour coveted by all nations. Some people may wonder what is gained by attaining such tremendous automobile speeds. They are not merely “stunts,” which require a deal of courage, but are crucial tests to determine whether the le'ssons learnt from experimental superlative mechanism can be turned to advantage in the construction- of the modern motor car. Had it not been for automobile racing, the car of to-day would not be nearly as efficient, reliable and durable as it is. All motorists to-day owe much to racing drivers and record-breaking automobiles. These supreme tests of speed and endurance have provided data for metallurgical experts, who, by noting the results of super-stresses, have enabled car manufacturers to produce more easily handled and safer motor vehicles. Such efforts as those of Captain Malcolm Campbell and the late Sir Henry Segrave, whose record of 231.36 m.p.h. Campbell increased to 245.736 m.p.h., cost a lot, but the data gained is invaluable to the automobile industry and not obtainable in any other way. Look at tho advances made in tyre construction during the past 10 years, thanks to the knowledge gained by subjecting tyres to the terrific stresses and strains involved at super-speels. The long life of present day motor tyres, giving at least four or five times the mileage of pre-war days, owes much to men such as Campbell, Segrave and other notable drivers, and the enterprise of those who spend large sums of money so that automobiles may be safer and better. As to the risks to life, they are well worth while, because they provide for the ultimate safety of millions of users of automobiles. One thing is certain, the efficiency of the modern motor car is materially due to the lessons learnt from racing.