MOTORING & MOTORISTS

Evening Star, Issue 19328, 14 August 1926, Page 16

MOTORING & MOTORISTS

[BY RADIATOR.]

LIGHTING-UP TIMES. To-day ... ... Sunday - Monday - -. 5.48 Tuesday 5.50 Wednesday Thursday ._ ... ™ ... 5.52 Friday - , 5.53 ' HINTS AND TIPS. —Mounting Tight Rim.— Every motorist has experienced trouble in mounting rims. The rim seems suddenly to have shrunk so that the jjoint persists in striking tho wheel felloe. A small .screw jack placed-in position on the hub can bo used to spring the point of the rim outward far enough to permit the rim to be slipped into place. —Broken Push Rod.— In the event of tho push rod of an overhead inlet valve breaking during a journey it is sometimes possible to finish the run by arranging for the valve to work automatically. This is clone by attaching one end of an auxiliary spring to the push rod end of the rocker, the other end being secured to some convenient paid of the engine or chassis, so that it acts against the ordinary valve spring. Should a coil spring not bo available, strong clastic may be used. The tension of tho extra, spring should bo arranged so that tho valve just closes, but may bo pushed open with one finger. When tho engine is running the suction produced on the induction stroke will bo sufficient to open the valve, while at tho bottom of the stroke the valve, will automatically close. —Temporary Dash Clock.— The owner-driver whoso car is not fitted with a dash clock, and. who does not wish to go to the expense of purchasing and lifting a reliable one, can arrange a simple and convenient suit stituto by cutting two small slots through the facia-board of a size and distance apart suitable for threading through them the leather straps of an ordinary wristlet watch, the buckle being secured in the usual manner ar the back of the board. The slots can be made quite easily by drilling three or four holes, say 2-1 Gin diameter, in a row, close together, and cutting out the rough edges loft, finally filing the slots smooth with a small, flat file. Very little space is taken up by this arrangement, and tho appearance of the facia-board, either with the watch in position or not, is in no way sacrificed. DRIVE CAREFULLY. Knowing bow to drive carefully lias much to do with tho motoring comfort, and is a big factor in the life of a car. No matter how well designed and how carefully built, and no matter how high the quality of materials, unless tho operator knows the proper way to handle it that car will develop premature weaknesses. There are thousands who, no doubt, sincerely believe that they are first-class drivers, but in whose handling of a car an expert could find plenty of defects. “One of tho worst faults in driving is placing unnecessary dependence on ornergeficy brakes.” Drivers can be observed 'almost any day going madly into traffic congestion, slamming tho brakes on, and bringing the car to a jerky stop. Tho intent is to try to get as near as possible to tho car ahead without bumping it. Of course, this wears out brake bands, which soon begin to squeak and annoy tho nerves of citizens. SPARK PLUGS. The efficiency of an internal combustion engine may bo greatly impaired by defective spark plugs. Laboratory tests have revealed remarkable power losses through plug faults not apparent to the average motorist. Many popple believe that, as Jong as_ a plug ignites tho charge, it is fulfilling its mission with maximum efficiency. There is something to bo said for tho advice given by some manufacturers to tho effect that the plugs should be renewed every 10,000 miles. Of course, a plug may function for 30,000 miles, but the chances of trouble-free ignition for such a period are rare. Tho leaky plugs of twenty years ago would he useless in modern high-pres-sure engines. It is a popular, but often misleading, practice to tost a plug by laying it on the cylinder bead and accepting it as satisfactory if the sparks jump the gap in unbroken sequence. A spark at atmospheric pressure is no guarantee of perfect functioning under compression. A cracked porcelain may not manifest itself in the air. When the engine is running on all cylinders the increased resistance at the gap duo to high compression may cause the spark to short-circuit through a crack. Burnt electrodes arc another cause of trouble. Ft is useless to reduce tho gap when the plug points are worn very fine. A sharp point becomes red-hot and may pro-ignito the gas. FOCUSING HEADLIGHTS. Often a driver may have quite a good idea of how to run a car, may have a good general knowledge of simple tuning and running repairs, and yet is quite ignorant of the really very”simple art of focusing head lamps correctly. It is, of course, necessary that tho greater part of the light should bo concentrated at tho focal point of the reflector, for the light is only reflected in the form of a parallel beam if it is situated at the exact focal point. If tho bulb bo nearer or further from the centre of tho reflector, tho light will bo thrown in all directions, and the chances are that a dark circle will exist in the middle of the road, while the banks at tho side, the tops of trees, and telegraph poles are brilliantly illn■minated. This arrangement is obviously unsafe, except for slow driving, as the driver is not enabled to see a sufficient distance ahead to lie able to pick out any potential approaching clanger. The procedure when focusing head lamps is to select a straight, dark road, with trees, buildings, or something to catch the light on each side. The bulb is then pushed in, or, if necessary, pulled outwards until the best position is arrived at, when the road ahead is clearly illuminated. Generally, it will be found that, up to a point, the farther back that a bulb is placed in the reflector, the longer and more penetrating the beam. At tie same time, it will be found that, if the bulb is just a little forward of the point at which the longest beam is obtained, a broader, and therefore more suitable, light for driving at moderate speeds will bo obtained. Many motorists make a practice of focusing the off-side head lamp for the longest beam obtainable, setting the bulb in the near side lamp so' as to give a fanshaped, close-range spread of light. Obviously, efficient focusing is not very valuable if the lamps do not point in the required direction. Many bead lamps have universal mountings, which allow of them being set in any desired direction, but on others the brackets are bolted rigidly to the chassis frame, and have to be set by means of a

Brief awwtnrts of holiday trips, roads, and places of Interest m invited lor this column.

A/ CAR’S FAULTS.' The following letter was received by an American car manufacturer from a plaintive owner:— “In March, 1922, I purchased one of your six-cylinder touring cars. In the first place I had only driven the car 5,000 miles when a nut got loose on the chassis and I had to tighten it up. In the next 2,000 miles I had two punctures, which I had to fix at a oast of one dollar. I also got stalled in the mountains of Kentucky, and all my efforts failed to got the car started. This alone cost me six dollars twentyfive cents. The next day I was run off the road and rolled down a mountain, turning over three times. This sprung one of the bows in the top, which cost me seventy-five cents. “ Last summer I was touring in Mexico, and an insurgent shot a couple of holes in the gas tank, but I drove in some wooden plugs and fixed that. Coming back to Ohio I had to ford the Rio Grande River, and got the radiator plugged full of blue mud, and it took mo two hours to clean it out. On that trip of nearly 10,000 miles the car was one continnens bill for repairs. 1 had to spend fifteen cents for an exhaust manifold gasket, get two dote for the side curtains, which cost me ten cents, two screws for th<p floor board, four cents, and a piece of chamois to wipe off the windshield, twentyfive rente. I guess that is all, except for the gas and oil. I think you ought to stand for the above items. I also got arrested for s|iecding, but maybe j ought to stand for that myself.” BOLTS AND NUTS. In its complete form a car has an appearance of solidarity which is largely illusory. To the casual onlooker it has all the appearance of a one-piece job, whereas in reality it is made up of an almost incredibly largo number of parts strung together by means of many unobtrusive but vitaily important bolts and nuts. Rivets are, of course, used to . a limited extent for securing frame members, etc., but by far tho most popular typo of fastening is the familiar bolt and nut. These are used iu such numbers that their aggregate weight would be very considerable if they were made of cheap steel, the poor strength of which would have to bo compensated by an increase in tho diameter of the bolt; consequently, what is known _ as “ high-tensilo alloy steel ” is widely used for motor car bolts.

This is not tho only reason for tho use of alloy steel, however, another of importance heing_ found in tho fact tuat the vibration, always present to a certain degree, has a most destructive effect on cheap steels, known as “fatigue,” which ultimately leads to complete failure. Bolts made of alloy steel and properly heat-treated have a far greater resistance to fatigue than those simply turned out of bright steel bar. Then again, in many cases bolts are subject to wear, as, for example, in tho joints of the brake gear, so that it is important to use a steel of fairly hard characteristics.

To quote some figures, tho steel used for ordinary cheap bolts may have a strength in tension of twenty to twenty-five tons per square inch, whereas a heat-treated alloy steel can readily bo made of double the tensile strength, and with as good, or even better, ductility. Furthermore, tho resistance to fatigue may be as much as eight times as good for the alloy steel as compared with tho cheaper metal. Consequently, by using alloy steel considerable weight-saving is passible, and yet the factor of safety is greatly increased.

High-tensile alloy steel holts have, for these reasons,' been employed for many years in the construction of motor cav chassis. A careless mechanic will fit any bolt which happens to come to hand, while I even should he realise that an alloy steel holt is needed materials are apt to become mixed up and, in the ordinary way, there is not much to show the difference between one bolt and another. As an illustration of tho serious consequences which may occur from using a bolt of the wrong material, tb© bigend bearing may bo quoted; thus, if mild steel bolts were used to secure the bearing caps after overhauling an engine they would stretch or fail altogether, with very disastrous and expensive results. WHY SPRINGS COMPRESS. Every now and then-a car owner will see something be never noticed before, just the ether day an experienced oivrvor watched a mechanic start off with his car, and was surprised to see the rear springs compress in an odd way when the clutch was let in. At once he suspected that there was something broken, else why should the rear of the ear bo so flexible. This led to the information that his car employed “ Hotchkiss drive.” It is a more flexible type of drive, with advantages and disadvantages. Cars without this feature use torque rods or tubes. When the power is applied to tho wheels it passes through these rods, not through the springs. The springs, therefore, do not compress in skirting. DEMAND FOR PETROL. There are several reasons why tho production of, petroleum is looming up us one of the most vital and interesting problems of to-day. The invention of the Diesel engine, tho conversion of tho world’s navies from tho use of

coal to oil fuel, and tb© vast expansion of motor transport, have caused such a huge demand for petroleum that alarm lias been felt as to whether tho world will always be able_ to yield enough of it to meet our requirements. On the surface this uneasiness would appear to be justified. Barely thirty years ago the motor_ car was little more than an interesting and enmbersome toy. To-day there are 15,000,000 motor vehicles in the United States alone, and Groat Britain maintains over 1,000,000. About 24 per cent, of the world’s merchant vessels ueo oil for boilers, and nearly 3 per cent, are purely motor ships, while the British Naw, the most powerful single power entity iu the world, has become _9O per cent, oil-fired, as compared with 45 per cent, before the war. TIGHTEN UP. In no way docs the old adago “ A stitch in time” apply more aptly than with regard to those parts of a motor cycle which arc subject to vibration. Tho motor cycling beginner will, therefore, lie well advised to give periodical attention to the security of such items. _ . Tool hags are notorious offenders in this respect,' and their fastenings to the carrier or frame should be made as perfect as possible, spring washers being fitted where necessary. The disposal of tho contents of the tool bags is also a point to which a certain amount of care should bo given, if annoyance is to bo avoided. _ Tools and spares should not be put in carelessly, but well packed so that no movement or rattle may take place. Tho attachment of mudguards also calls for attention, but as the, nuts on mudguard bolts are usually in an inaccessible position between the guard and the tyre, their security is, as a rule, neglected until slackness is only too obvious. At any time when the wheel is out, the application of a spanner is advisable to ensure that there is no looseness in these connections. Spring washers should be employed wherever possible. Occasional attention (say, every 500 miles) should be paid to the engine and frame bolts. Very probably these will be found to bo quite secure, but tho knowledge that such is the case in- J spires in tho rider a happy confidence in his machine. Other items which call for occasional attention, if vibration effects are to bo avoided, are tank and chain case attachments, petrol and oil pipe connections, and accessories mounted on tho handle-bar or elsewhere. . , Although not strictly coming under the heading of vibration, slackness in wheel, fork, and steering head bearings should bo also rectified when found necessary, as the effect of undue 'play in those bearings is very much greater than tho slight amount of looseness would appear to warrant. INEFFICIENT BRAKES. After you have had your brakes adjusted or relincd is the time for another brake test. The danger is that in correcting one fault you have created another, and your brakes may be dragging. Fortunately, brakes don’t go had all at once, and as they become less and loss effective the driver just naturally applies them earlier and more energetically. However, iu emergency ho cannot stop as quickly as ‘ho should, so that he is risking accident as long as the brakes are not at their maximum stopping efficiency. The opposite fault with brakes, on j tho other hand, may exist without the | driver realising it, though if ho did ho would be just as eager to correct it as to repair brakes that fail to stop the car efficiently. , This second fault is dragging brakes —brakes that are too tight, and therefore exert a constant drag on the engine, with a corresponding increase in fuel consumption. On an up grade climb the least drag seriously affects tho performance of the car.

The fact that dragging brakes are costing the driver money' for wasted petrol is enough to make most owners correct this fault. The trouble is that few of them realise when this condition exists.

Here is a test that anyone can make for himself: On a well-paved level road attain a speed of thirty miles an hour, then shift into neutral and coast. Begin timing your deceleration when the speedometer shows twenty-five miles an hour; at the end of sixty seconds your car should still bo rolling five miles an hour or faster. If it isn’t look for dragging brakes.

A more certain test can bo made, and is well worth while. Jack up both rear wheels, arid, with the shift lever in neutral, turn onch wheel forward by band, first one and then the other. If the brakes are free the opposite wheels should turn backwards easily and evenly. Any “ swishing ” sound or resistance indicates that the brake drums are making contact with the bands.

If the bands are too tight readjust them. In many cases, however, the dragging is duo to out-of-the-round bands, which must bo trued up at a service station. Whatever the cause, correct the faults at once. Save your brakes; don’t wear them out at the expense of petrol economy and performance ability. Remember that a free-running car, with quick accelerating powers, may often avoid a mishap that could not be prevented by perfect stopping ability. Brakes are for stopping the car, not for overloading the engine.

PHOSPHOR-BRONZE CYLINDERS

In a rccont paper on ‘ Piston Temperatures in High-speed Petrol Engines,’ Professor A. H. Gibson, of Victoria University, Manchester, said that when trying out air-cooled engines it had been suggested that phosphorbronze cylinders should bo tried. Accordingly three cylinders were made from the same pattern of cast iron, aluminium alloy, and phosphor-bronze-copper alloy, and, curiously enough, the last mentioned proved the hottest and worst of the three. When the use of this alloy was suggested the argument was that the metal had an excellent wearing surface, that the ribs would be very efficient heat conductors, and except for the fact that it would be very heavy the cylinder should be a good one. At the conclusion of the tests some of the phosphor-bronze-cop-per alloy was sent to the National Physical Laboratory, and that institution informed them that its conductivity was lower than that of cast iron, which was a great surprise. OVERSIZE BATTERY. Prospective buyers of storage batteries often have a hard time deciding between several types of battery all suitable for their purpose. This is true, no matter what make of battery they choose to buy. “ Wo believe it is to the advantage of the user to have an oversize battery,” says the manager of a wellknown .service station “ Emergencies arise, and the car equipped with an oversize battery is better prepared- to meet them than the car with a standard or under-capacity battery. “ This is so obvious that it is seldom questioned, and the slight additional cost for the bigger battery is more than covered by the additional life it contains. One horse pulling a two-horso load will not last long. Two horses on the same load will grow fat on the job and always have the reserve strength to meet emergencies. The same is true of batteries.” CONTINENTAL RACERS. There are indications that horizontal supercharged two-stroke engines will make their appearance at an early date in international races. It has been well known in the industry for the past year or so that Fiat was working on an engine of this typo, but the Italian firm declined to make any statement. It may now bo stated that the now Fiats are horizontal straight-eights with two pistons per cylinder and two crankshafts connected together. Quite recently the first of the cars was driven on Monza track by Bordino, and although wonderfully good results wore obtained, it is still felt that they are not quite ready for competitive racing. There is every possibility of the cars making their first appearance in the

Italian Grand Prix on September 6. Two other horizontal two-stroke flat twins have been built and are being prepared for racing. One of these has been produced to the designs of M. Cauzan, a French engineer, and is being tried out in a motor boat. The engine is a four-cylinder two-cycle of 1,500 c.c., with the cylinders placed horizontally and having two crankshafts and two crank cases. A Rootos blower is used. After tests on the water, other engines will be built for racing cars. The Sima-Yiole two-stroke engines differ from the Fiat and the Cauzan in having one crankshaft and one crank case. Cylinders 1 and 2 and 3 and -1 are opposed, there is crank case compression, a blower eventually will be m-ed, and the mixture is delivered to the cylinders through a rotary distributor. THE KNOW-ALL. Have you a mechanical mind? The man with a mechanical mind always has a base suspicion that tbo makers of his car are ignorant people, who are content to follow the line of least resistance. He feels sure that he can improve npon their design without the slightest trouble. There is nothing he will stick at. The man with a mechanical mind is seldom seen on the road, because he is too busy in a garage to have much time for motoring. He prides himself upon his theoretical knowledge, and points with pride to his botched jobs and destructive “ improvements.” Still, he is happy, and, as long as he confines his attention to his own car there is no need to worry about him. But, keep him at a respectful distance from your own car, if you have to use a shot gun. HERE AND THERE. There were 141 Continental cars sold in New Zealand for the second quarter of this year, compared with 101 for the first quarter. * * * * From a description of the last Brooklands meeting:—‘‘Cars like meteors.” There’s a chance for the next new car producer—the meteor motor. * * * ■» The Hamilton Borough Council is taking steps to reduce the dazzling headlight nuisance. Motorists who have their headlamps adjusted receive a certmeato trom the borough traffic inspector. When mechanical assistance is needed it is provided by the council at small cost. After a reasonable opportunity has been given, motorists whoso lights do not comply with the by-laws will be prosecuted, *• * ' -x- * The ' Con Rod,’ tho orgap of the Douglas works, relates the following amusing story:—A customer of the firm had ordered a new tank for his machine; tho replacement, however, could not be made until the last moment before a bank holiday, and delivery appeared impossible, üßtil a director of the firm, who fivf-H rmnr the customer, undertook to deliver tho tank on his way home, lie drove up in his big Daimler to the man’s house, and knocked at the door. The customer appeared, took tho tank, and said; “ Uh, good! My tank' 'Thames very much, my man,” and, putting his hand in his pocket, handed the director a threepenny hit! “My man” thanked him solemnly, and walked back to his carl » * * » Paris police have powers to take action against firms putting horse vehicles on tho streets with insufficient power to ensure a reasonably fast rale of travel. * * » * A pessimist is a tourist who buys three gallons of gas at every village for fear he’ll run short. An optimist is a chap who reckons he’ll make the next town on the last quart. And the one who sS.y.i; “Oh, J guess there’s plenty of oil ” is a plain fool. * * & An expert employed by an American tyro company covers IUO,UOO miles a year in testing balloon covers. *- « H There are two kinds of motorist—the owner-driver class and the owu-a-driver class. * -x- * « Four of the fastest cars in the world appear to bo at present in England. These are Air J. G. Parry Thomas's “ Babs,” with the record of a speed of 170 miles per hour on Pcndine Sands, Wales; Major H. 0. D. Segrave’s Sunbeam “Special”; Mr Malcolm Campbell’s twelve-cylinder Sunbeam, which made many records at Faroe Sands, Denmark; and now Prince Djelalledin’s straight-eight racer, designed like a knife, and only capable of holding one person, the driver. The Egyptian Timco was to attack the Bendino records, but nothing has come through yet about it. a « » * By winning the 1926 Junior T.T., A. Bennett has accomplished a triple hat trick (three T.T. races, throe ’Belgian Grand Prix, and four French Grand Prix) . * * * « A nut with a stripped thread can be made serviceable if it is refined with solder and started on the bolt so that a new thread is cut in tho soft metal. A bolt may be similarly treated. Tho host method is to apply tho (lux and then dip the part in melted solder. * ♦ Tho applications of German motor car manufacturers for space at the British Olympia Motor Show to be held in October have been refused. Rust may be removed from water jackets if a filling of vinegar is allowed to stand two or three days.