DRIVERS' ROADSIDE PREDICAMENTS.
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Mechanical -Aids to Getting Out of Trouble. Getting Under Way Again With a Loosened Wheel or Other Axle Defect. Dealing With Overturns.
OWING TO the amount of thought which has been bestowed on the design and manufacture of commercial vehicles, mechanical troubles are becoming less frequent, and it is fast getting to be rare to see a lorry held up through some trouble which the driver cannot remedy in a few minutes or, at any rate, in a reasonable time. In spite of this, it is as well that every driver should know how to deal with troubles -when they occur, and that he should be provided with means which will, at least, enable him to get his vehicle to some place where a permanent repair could be carried out.
There are certain precautions, also which must be taken when a mishap occurs, and to these we shall refer in their proper place. One of the greatest temptations is to continue using a makeshift because it seems to be satisfactory.
Despite the increasing rarity of mechanical troubles (in fact, largely becauge thereof) the effects of untoward circumstances, or of inexperience or bad judgment on the part of the driver, are occasionally ' to be seen, and many a lorry has, in consequence, blocked a crowded thoroughfare for hours, or has meen derelict on a country road through some mishap which, had the driver had better knowledge, might have been temporarily remedied. .
A weak spot in vehicle design that seems to persist is in the wheel fastening. Instances occur in which the nut on the axle sleeve may strip, or the threaded part of the sleeve may break away from the sleeve, with the result that the wheel will tend to run off its axle. The firstsymptom of this is that the splines of the floating axle no longer engage and the wheel ceases to drive. In a case of this kind no permanent remedy is possible on the road, but simple means are usually at hand whereby . the vehicle can be towed with safety to a repair shop. The very crude device of letting down the side of the body (provided the body is of the kind tha witl permit this to be done), and securing it with ropes to the frame as shown in Fig. 1, has been known to enable a lorry to be towed with safety (for, of course, it could not in its condition be driven). In cases where the side could not be let down, a beam of wood or iron slung across the wheel, as shown in Fig. 2, and prevented from
swinging outward by ropes
tied to the frame has retained a wheel in place • while the vehicle was being towed. The same dodges are equally useful in the case of a chain-driven lorry, where the screwed end of the axle has broken away.
In the event of a broken front stub end the matter is more difficult to deal with. The fact of the wheel -being a steering wheel renders it impossible to keep the wheel in place from the outside. The best course in such a case is to remove the stub axle and to take it to some place where a hole can be drilled and tapped in the end, as shown in Fig. 3; a stud cart then, be fitted which will keep the wheel in place whilst the vehicle is got off the road. It would, of course, be a criminal act to attempt to finish a journey with a wheel only .held on by such a tern-. porary means, and it is here where common sense should be exercised, for many a,driver, finding that he is once again on the move, will often allow extraneous conditions to induce him td carry on with a journey instead of giving the time to a proper. repair or replacement.
Where a lorry has to be towed, it is not uncommon to see a driver put a rope through both dumb-irons in such a way that it forms a triangle. The effect of this is to bring a very severe strain to bear on the dumb-irons in a sideways direction, tending to bring them together. Dumb-irons are not designed for such strain, and the result is that they often get badly bent, and occasionally they actually get Fig. 3.—A temporary means of holding a front wheel in place with a broken stub end. broken off. In Fig. 4 we show the right, way and the wrong way in which to attach a rope to the dumbirons, a rope to each dumb-iron being correct.
Sometimes it is found necessary to have an axle or steering
arm straightened after an
accident. It is not always possible to have this operation carried out by persons who are familiar with the kind of steels of which motor axles are made. An ordinary blacksmith, when he wants t o straighten any bar where the bend is confined to one particular spot, usually heats it up in his forge, and, to confine the heat to the particular locality of the bent portion, he 'cools down the portions which are not bent by pouring water over them. By this means he can confine the heat to the exact spot he requires for straightening. This is quite the correct way of tackling such a job, but, unless his attention is called to the fact that the steel of which the axle is made will become dead hard, and consequently brittle at thevart where it has been cooled, he is likely to leave it in this condition. He should be warned that the part so treated should bc heated to a dull red arid then allowed to cool down gradually.
Should anything go wrong with the differential gear, so that driving becomes dangerous or impossible, it is the common practice to remove one of the spiders in the driving wheel so that the lorry can be towed without imparting motion to the transmission shaft. It is, however, a far safer plan ta remove both spiders as, if only one is removed and the distance to be towed is a long one, there is likely to be trouble through the internal pinions of the differential seizing on their pins. These
FIg.4.—The wrong and the right way of passing a towrope through the dumb-irons. The wrongmethod will inevitably result in bent irons.
parts are not designed for prolonged movement and, if kept running for some time, will invariably give trouble.
The extra time and trouble involved in the removal of the second spider will always be more than compensated by the avoidance of considerable further trouble' and delay.
It is usual when towing a lorry to allow a fairly long length of rope between the two vehicles. There have been cases where pedestrians have not noticed the towrope and have made a dash across what they have taken to be a clear space between two vehicles, with the result that a bad accident has happened, as the driver of the leading vehicle cannot see what is going on behind him and, consequently, does not apply his brakes. A wise precaution is to tie some pieces of paper at intervals along the tow rope.
When the vehicle has to be towed some distance, paper cannot be relied upon Jong to remain in place and it is, therefore, better in these circumstances to use white rag as a warning to the careless.
Should a lorry be overturned in a narrow road it is often very difficult to get it righted again. On a road of sufficient width it is usually possible to attach a rope to some part and by the pull of another lorry to right it again, but in a narrow roadway it is impossible to get the pull in the direction required unless some special means be devised. In cases where a tree or other suitable means offers for an anchorage, it is possible by means of a pulley, as shown in Fig. 5, to right a vehicle, however narrow the lane may be.
The hauling should be taken very easily and slowly, and two or even more check ropes should be fastened to a frame member and be passed over the side of the lorry, taken back, and be paid round tree trunks, so that as the vehicle is righted it shall drop softly on to its four wheels. Otherwise considerable strain will be imposed upon the springs. For a lorry to turn turtle'is, fortunately, not a common occurrence. Such accidents, however, do happen and when they do they give serious trouble in righting the lorry again. In Fig. 6 we show a method whereby a vehicle can be righted provided there is means of getting sufficient pull at the rope. Two timbers lashed together at the top, and butting against some part af the frame, will support a rope in such a manner that it will tend to raise one side and bring the machine again on to its wheels.