New Equipment for Sporting Cars & Motor Cycles, September 1924

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Motoralities.

Lucas Motoralities seem, to those of us who have been long “on the road,” to be part of motoring, without which the sport would not be altogether complete. The Lucas Festoon dash lamp is a pleasing item in. this attractive series of accessories. Its name is almost a description in itself, as the lamp is festoon like, being a metallic cylinder, with glass window, containing a neat double ended incandescent globe. Its small bulk makes it particularly admirable for use inside the hood, where the need for folding reduces the available lamp space, while its light is ample for either that purpose or for reading the various instruments when it is fitted as a dashboard lamp. The cylindrical body can be rotated to throw the light where it is required, while turning the body right round, until the glass faces the base of the lamp, automatically switches off the light, so that a separate switch is not required with this model. The body is held in position by a spring plunger, and can be

instantly removed for bulb re placement, as is apparent from our illus

tration.

Mention of bulb replacement reminds us of another Lucas accessory which is of value in that connection, namely, the Lucas spare bulb cases. These cases, which are made to a patented design, are in two patterns, according to capacity. The larger one, known as model 17c, carries two headlamp bulbs, four small bulbs, for side or tail lamps, and one of the abovedescribed festoon lamp bulbs. The smaller pattern carries one headlamp bulb, and four small ones. The bulbs are retained in the end covers, and by means of skeleton inner cases, which can be easily removed when required, but which will not fall out when the end covers are removed. Spring clips are provided to hold the bulb cases, and on the majority of cars it will be found convenient to secure these to the woodwork of the dash underneath the bonnet, in a vertical position. Alternatively, the clip may be screwed to the inside of the toolbox.

These accessories are obtainable from Messrs. Lucas, Ltd., Birmingham.

An Efficient Plug Tester. To the keen sporting driver there frequently comes the desire and, less frequently, the actual need, to inspect the working of his sparking plugs. There is thus real need for a proper instrument to carry out that important operation, for there can be no denying that the familiar screwdriver, regarded as a tool for this purpose, has many disadvantages. Quite apart from that there is risk

the fact that there is risk of shock when using a screwdriver, and that intelinittency of spark when it is being used as a tester, may just as well be due to inaccuracy of hold by the user, there is also the circumstance that its application fails to impart to the operator the knowledge he requires as to whether a plug is shorting internally, or broken, or whether the spark is actually too feeble to fire the charge regularly at all speeds. The Mitchell Plug Tester is a scientific instrument which eliminates all these both of commission

both and of omission. So far as appearance goes, it is a neat polished vulcanite tube, resembling in size, as in finish, a fountain pen. At one end there is a round metallic knob, or conductor, and at the other, a red cap, pierced with a hole which is needed for a special purpose. There is a window in the middle. When the conductor is applied to the top of a plug, with the engine running, a series of orange flashes appear in the window, each flash coinciding with the timing of the spark at the plug points. The intensity and regularity of the flashes indicate the character of the spark. The nature of the flash indicates the condition of the plug, and a sheet of instructions, issued with the indicator, tells the user how to read their meaning aright. An integral part of the complete tool is the detector, which embodies a length of insulated wire, and a metal

casing. The wire is designed to connect up with the tester, by means of a plug which enters the hole in the cap of the tester to which reference has already been made. The effect, when the case is laid on the engine, is to cut out the plug which is being tested, and to intensify the flash in the tester itself. It enables the character of any flaw in a plug to be accurately determined.

The complete outfit costs only 8/6, and the manufacturers are The London Motor Supplies Co., 1, London Road, Twickenham, Middlesex.

The Solex Carburettor.

In certain respects the Solex carburettor enjoys an almost unique reputation. The carburettor which enabled the two Sunbeams, for example, to win first and second places last year in the French Grand Prix—for speed—and which also made it possible for the Mathis to come in first and second in the French Grand Prix— for economy—is not one which is likely to escape the notice of any one who takes the slightest interest in car performance, whether on track or road, whether in competition or in ordinary touring use. Yet those are only two typical successes with which the name of this carburettor is associated, and if we must mention one or two more out of the many, we should pick the 200 miles race at Brooklands which has been won by a car

fitted with a Solex carburettor three years in succession. With a record such as this, the principle of its working hardly matters. Deeds, not words, are the motorists requirements, and the Solex has plenty of those to which it can point. This carburettor is made in two standard types, the vertical and horizontal models, in order to meet the requirements of various engine designs. The horizontal model, in particular, is well adapted for fitting to those engines in which the induction passages are cast inside the cylinder block. In addition to the standard types, special Ford and Morris models are also made. The

price of the last named is but I2S. 6d., complete with petrol pipe in position, control rod attached to throttle lever, and adjustment for slow running. The manufacturers are S. Wolf and Company, Ltd., 115, Southwark Street, London, S.E. 1.

Winton Valve Grinder. One of the most little tools which we have

we seen for some time is known as the Winton valve grinder. It has been specially designed for use when grinding the valves of all side-valve motor cycle engines whose sparking plugs are screwed into the valve caps, such as the Triumph, A. J.S., Norton, Enfield, Sunbeam, to name but a few. Its construction is apparent from the accompanying illustration. The body of the tool is a plain cylinder, screwed at its lower end with the same

sized thread as a standard sparking plug, presumably so as to be “finger tight” in the hole for the plug in the valve cap. This body portion has a plain screwed cap with knurled edge. Inside it is a spring, which bears at its upper end against the inside. At its lower end there is a ball-thrust bearing which serves to separate the spring from the collar of the central spindle, which is really a screw driver, and is shaped in the familiar form of that tool at its lower end. This spindle is free to rotate in the body of the tool, and is located, in a vertical direction, by a butterfly nut, engaging with a screwed part of the spindle, and affording adjustment for the height. A couple of slots, at right angles one with the other, are cut in the top of this spindle, and a tommy bar, shaped so that it will conveniently engage the slots, is provided as part of the equipment. An important part of the tommy bar is the overhanging lip at its end, which prevents it from slipping out of place when in operation. The tool is as simple in use as it is in construction. One proceeds as follows :—Apply grinding paste in the usual manner to the valve face, and set the tool up, the butterfly nut having first been screwed well down. Hold the tommy bar in the slot, and with the free hand screw the butterfly nut back until it is quite free of the body of the tool. This ensures that the end of the screw driver is resting, under pressure of the internal spring on the top of the valve with its edge ready to drop into position in the slot, which it will if the tommy bar be turned slightly. Subsequently, adjust the butterfly nut until satisfied that the pressure between valve and face—which is automatically applied by this tool—is approximately

that which is thought to be desirable. Then proceed with the grinding of the valve along orthodox lines. The retail price of this tool is 4/11, or 5/3 post free from the makers, J. Froome & Son, 2 and 3, St. George’s Street, Winchester,

Honing Worn Cylinders.

The actual wear in cylinders, although enough to affect the running of the engine to a considerable extent, rarely measures more than a very few thousandths of an inch. To correct this comparatively slight inaccuracy it has hitherto been considered necessary to have the whole block removed and rebored in special machinery which is made for the purpose. This is a costly job, involving, not only the expense of the use of that expensive machinery, but also the wages of highly skilled men, whose labour is necessary if the job is to be a good one, and, in addition, all the overhead charges, which are inevitable and considerable in connection with a job of this kind. It is now suggested that all this expense and trouble is quite unnecessary, and that the cylinder can be put in perfect condition by honing. Moreover, in cases where the engine is equipped with a detachable head, the job may even be done without removing the cylinder block from the engine or the engine from the frame. The

or apparatus employed for this purpose is very like a reamer from which the cutting tools have been removed, their places being taken by long hones, very similar to those

used for setting razors. The hones are mounted in long guides which are maintained parallel to the axis of the tool by spring-pressed cantilevers. There are four hones, and the pressure is carefully and equally distributed between them, so that there is the same amount of cutting, or honing, done by each. Cylinders which have become tapered, the bore -of which has barrelled, or which are oval, can all be cured by this method, it is claimed, so long as the amount of metal to be removed does not exceed one hundredth part of an inch, which is equivalent to saying that ninety per cent, of all cylinders which need reboring can be tackled by the ” honer.”

Amongst the several points which are claimed to put this method of cylinder treatment ahead of the orthodox grinding, we may quote : that the operation gives a burnished surface which does not tend to seize; that the work may be done by any ordinary competent garage mechanic in time which, in the case of Cylinders with detachable heads, does not exceed twenty minutes per cylinder bored ; that no grinding compound is used, so that there is no risk of its getting into the bearings or other vital part of the motor, and that the job, when completed, is every bit as good in itself as that of regrinding.

The equipment for this method of cylinder repair is being marketed by Morris Russell & Co., Ltd., of Great Eastern Street, London, E.C.

A New Shock Absorber. A shock absorber of the friction type, but embodying

a rather ingenious means for automatic adjustment of the pressure between the discs, according to the degree of movement of the axle, has just been placed upon the market by Industrial Rubber Products, Ltd., Brook House, Tottenham Court Road, London, W.I. In general outline this fitting does not appear, at first sight, to differ, to any great extent, from others of the same type. A closer examination, however, reveals the fact that it embodies several novel features of utility as well as interest. In principle, it consists of a pair of banjo-shaped arms, mounted, at the centres of the circular portions, upon a common spindle, and having the outer end of the arm of one banjo pivoted to the, axle and the other similarly attached to the frame of the chassis, or its equivalent. Each of these arms is, as a matter of fact, the equivalent of two arms, since each consists of a pair of parallel plates of the same shape. There are thus presented, at the fulcrum about which the arms are hinged, four discs of steel, that being the material of which the arms are made. The four arms are alternated, so that there is first a disc of one, and then a disc of the other, and so on. A fifth disc, independent of both arms, and serving a special purpose,

to which reference will be made later, is located in the middle of the four. Between each disc and its neighbour is another, a friction-provoking disc, of wood. The central independent disc has two projecting lugs, of which the owner, by making use of a special key, ghich is provided as part of the equipment, can take hold and, rotating the fifth disc by this means, ascertain the degree of effectiveness of the frictional grip between the discs, adjusting it accordingly. It has been stated that the arms hinge upon a central

spindle or bolt. This bolt, with its complementary nut, provides the means whereby the frictional damping effect of the device is graduated in accordance with the movement of the axle. The nut itself is carried by a locking ring with a notched edge, into which a spring pawl, secured on one of the arms of the shock absorber, engages. This pawl, besides preventing the nut from slacking back unintentionally, under the influence of vibration, also serves to ensure that the nut always moves in unison with that particular arm to which the pawl is attached. The bolt itself is also prevented from turning, by means of a key which engages with the other arm and, just as the locking device for the nut ensures the nut oscillating with its arm, so the key which secures the bolt provides that the bolt itself shall oscillate with the other arm. The nut is, therefore, continually being screwed up and down the bolt as the shock absorber moves, so that it only remains to arrange the parts in such a manner that, as the axle approaches the frame, and the need for frictional resistance increases, the nut is tightened, squeezing the plates together. It follows naturally that, as the axle approaches its normal position, the compression of the plates is reduced, and the damping action is at a minimum.

This absorber is named the “Excelsior,” and we understand that it is made in various sizes to meet the requirements of all types and weights of cars.