MOTORING

Nelson Evening Mail, Volume LXI, 14 April 1928, Page 4

MOTORING

i NOTES FOR THE OWNERDRIVER

i WHEN THE CURRENT FAILS i j MAKK SYSTEMATIC TESTS | Ortliuui'ilv a motor cur is i't»nsidoretl las ;i vehicle propelled liy petrol, itiul I rightly so, but it is also a vehicle in the operation ui' which electricity plays ,a \ ital part. » If something goes wrung, the first thing to inspect is the fuse, it any is | provided. Having found this in good condition, the condition of Ihe battery '• bhould next be investigated. Find, out jit' it i- charged: this can be determined by using a hydrometer. Then each ; successive terminal in the circuit leading from the battery should be tested. for instance, tin-re N an insulated wire ; leading down tu the lighting switch. I The first place to test it. after nuikillg ' sure thai the battery is all right, is at the metal terminal on the switch. It' ; no current is there the wire may be I broken or the terminal connections j may be poor. In any event the trouble. ! must be limited to this one small stretch of wire.

In niiiking the test Use a long piece of insulated wire with a six (or twelve. as the case may be) volt bulb inserted in the middle, of the wire. Disconnect at the switch the wire to be tested and connect this with the test wire. When the other end of the test wire is touched to the other term ilia I of the battery (lie. light should burn, if the wire leading from the battery to the switch is all right. If the light burns, lest where (ho wire leases the switch for the device to be operated. If the current gets to the switch and dues not get out of it, it is apparent that the. trouble is in the switch; but if it gets to the switch, yet not through the fuse, the hitter is to blame. If the current leaves the fuse but, does not get to (lie headlight which the switch controls, then the trouble is in that wire somewhere. If the current gets to the lamp, but the lamp will not, light, the diflieulty is in- the. lamp. If the current is traced through the lamp but does not reach the battery, then the wire leading back to the battery is at fault. If the current is carried back through the frame, as is often the case, the ground connection niav he at fault. Electric troubles on motor vehicles include the ills of horns, which become silent or faint, and in either case cause, considerable annoyance in driving. FRONT-WHEEL BRAKE INTERESTING! TYPE

A very interesting type of frontwheel brake is manufactured in France', known as the Eclair. It aetr, on the electro-magnetic principle. As a result there arc no brake rods or cables, braking is absolutely progressive, and adjustment automatic until the lining is worn out. The electro magnets consist of a number of eoils disposed in a brake drum carried on the stub axles. In the place of the ordinary drums on the hubs are carried cast-iron annular discs, which are normally held away from the magnets by light springs. The brake pedal works a rheostat in such a way that the amount of current reaching the electro magnetic coils varies with the extent to which the pedal is depressed by the driver. Braking is naturally absolutely effortless, for there is no reason why the brake pedal should be any harder to depress than the accelerator. Simplicity also is ii great feature of this brake, as the parts merely consist of a. steel drum equipped with the magnets, a, east-iron ring, and rheostat. Needless to say the efficiency of the brakes is just as high when the car is stationary as when it is running, while it. is claimed that the current consumption is actually less than the average pair of headlamps or similar electrical device. It should be pointed out, of course, that should there be any failure in the supply of current to the brakes these will bo non-operative, but it is claimed that this type of front-wheel brake can easily be adapted to cars having roar brakes only. AIR PRESSURE LONG LIFE FOR TYRES A pneumatic tyre obviously cannot be a pneumatic tyre unless it contains , air. What is often forgotten, however, is that the exact amount of air which it docs contain is quite a vital point, and one that determines whether it will, so to speak, live all its days, or die a premature and costly death. A prominent firm of tyre mauufac- ; turers supplies a table showing the I various pressures at which various I sized tyres should be used. These, of ! course, should be strictly adhered to, but it must be remembered that tho air pressure can also fall through slow puiictures or leaks, as well as through sheer neglect, although investigation does show that more than two-thirds nf the damage done to tyres is due to ill-treatment. There would, for example, be a very big decrease in the number of punctures if motorists would examine their tyres at regular intervals and pick out any flints, or nails embedded in the cover. If. on removal, a fairly deep bole be left, it ought to be filled immediately with trend compound. It is estimated that seventy per cent, of punctures are caused by sharp substances which, as they are not removed, sink deeper, and deeper, until they pierce the inner tube. Cuts too, which penetrate the easing should be repaired with a strong patch giving adequate support, otherwise the fracture will extend and cause a largo burst. Another reason for the. blowing out of the wall of a tyre is the air escaping from a puncture and filtering along between the cord material and the tube, accumulating there in a sort of blister or pocket, which ultimately bursts the cover. The explanation of why the air passes between the cord and the rubber is that continual running of the tyre at ;i \cry low pressure has. through the great bending and flexing strains on the walls, loosened the lubber from the cotton.

Jll Midi ;i fuse the whole ilifiieulty rould probsibly lie iivoidcfl wore the tyres kept sit their correct pressure, ,'ind Mm usti 1 or stone picked out before piercing the casing. Properly inflated tyres solve iilniosl every lyre problem—if the tidditiotiiil nir bus not come 100 late. The nir pressure in lyres should be tested once every week. THE INNER TUBE HUMBLE AND UNSEEN WORKER INTERESTING MANUFACTURE Although It. does ifa work humbly and unoeen. the motor tyre tube is the

important and indispensable ally if (he outer-cover. It is imt decorated with any pattern; it is an inartistic shade of pink: it never gets any praise, it is the lii-t in receive abu-e': yet without it tin 1 outer cover would be tiselc-s.

Pug tubes, little tubes, thin lubes, fill tubes from the mill- are issued in vast quantities to the call of motorists throughout the world. Fascinal in;: t<> watch i.- I he cvolul ion of :i motor tube. There is no gradual* ness about it: great lumps of red rubber compound, looking not in the least like a t uhc. are fed into one end nf what appears to be a -ausnge machine and out of the other end come yards and yards ol motor tubes—and 'thai is really all there is To it. ;! .! though the tubes arc not ready for the road ju-.t yet.

Ah soon as they appear from tit.; •■f-ausagc machine." each tube is pluced (Mi a mandrel and then vulcanised When it is taken out of the uileanb.-.'i

the ends are joined up by an ingeniou automatic joining machine which vulcanise.- simultaneously both inside -ind out : the valve hole is punched and .-iilut ioiied iind the tube re-enters the vulcanising chamber for the completion nf the '"cure"' as the process i- called. After that the valve i- lixed in position and the tube is inflated ready to be tested. Girl operators slip it over the spoke- of ii large rimless wheel which, first stretching it to it-- correct size, carric* it under water, while the girls watch with eagle eye for any nf flic tell-tale bubbles that mark imperfect work. Such a tube is rejected: while i lie perfect ones are dellated. marked wiih their size, packed and sent into store.-. From iMicrc. of course, they, in partnership with their outer covers, go in ;ill parts of t he continent'. I-lOSK VJ.'oTKt Ti>l: Oil is the deadly enemy of rubber. It is ii good plan to protect the inlet hose from the radiator to the pump from the effects of oil by giving it ;i (•oat of shellac and then a couple of layers of tape and shellac over that, The shellac prevents the oil soaking til rough and getting at the rubber. TO KEEP lirST FROM RIMS To remove rust from rim- it is nece.s sary to scrape and sandpaper the Mil

lace, M'tei a thorough cleaning tip • ,|> a '";ii "t ordinary shellac mixed with Mime graphite. When this is div applv another coiil. All aluminium pa iui will improve I he looks ..t' the rim it it i- fb'sired and « ill mmv e t he same purpose. _ | f i be i iii cads "t ii lug bolt are -i ripped vv hen changing a rear l\ re mi the road, borrow one from the front rim il an extra fug i- !l "t earned. Kvery lij.j In.|t i- needed on Ihe rear wheel-. a- tbe rim may -lip w hen pow cr and brake- arc applied, damaging the rim and valve stem. doles will appear in fenders it' the under side i- not cleaned and paint-'d occasionally. I.'u-t vvill cat its way through the metal v\ hen water comes in •■•ntaei with t lie i ivv surface. The car owner who -u-peet ? the ga.«-o-line line In the carburettor of being clogged '-an determine the accuracy n\ hi- suspicion in i few second.-. I'u.-h down on the carburettor thmt If it Hood- the line is clear. It it doc- not the line must be disconnected and cleaned.