CORRESPONDENCE.

New Zealand Herald, Volume LXI, Issue 18629, 9 February 1924, Page 12 (Supplement)

CORRESPONDENCE.

—Your correspondent Mr. E. S. Dukes in the Supplement of February 2, oasts an unwarrantable aspersion upon an exceedingly hardworked and conscientious class -when he declares that mechanics "purposely arrange for your car to coma back to' the garage for further work in a few weeks' time."

Unfortunately, occasional cases of negligence and even gross carelessness do occur where mechanical work on automobiles is concerned and the best of 'garage proprietors and repairmen realise this and. make strenuous efforts to prevent them, but to accuse the whole trade of "fiendish deliberation" and "wilful intention" is a disgraceful libel and an absurd suggestion. That it is absurd must be apparent to anyone who considers the matter for one moment. What firm could hope to practise criminal dishonesty of such a nature and remain on its feet for more than a. few months? There may be rare cases perpetrated by the here-to-day-and-gone-to-morrow type of repair shop, and if motorist's are so foolish as to entrust their work to mechanics of untried ability and unknown reputation, they have only themselves to blame if they end up m the nearest hospital. But Mr. Dukes fires his gun, loaded with utterly unfounded accusations, against the whole trade, and shows thereby that ho has little experience of firstclass motor repair work as practised in Auckland at any rate. I may say that I am in close business connection with 75 per cent, of the best garages in Auckland and have had every opportunity to observe their methods and the quality of fheir work. In addition to this I am competent to form an opinion by virtue of the fact that I am myself a motor engineer of considerable experience both in the Old Country and in New Zealand. I say without hesitation that Mr. Dukes has completely overstepped the < marks of good judgment and fair play in making a general accusation of deliberate dishonesty and intentional criminal carelessness against the garage proprietors. L. CotntTENAY Atwool. Sir,—Motorists who, like myself, have had a very limited experience with cars, look forward to such information as is from time/ to time put before them by "Focus," under the heading of "The Motor but the letter On "Motor Accidents "' "Why," bearing the signature E. S. Dukes, in last week's Herald supplement must have startled a very considerable number of car owners, experienced drivers or otherwise, and caused consternation to not a few, myself included. Sooner or later everyone's car requires attention through the development of some defect, mechanical or electrical, which it is beyond the ownerdriver's skill to remedy, but, according to Mr. Dukes, it is a common thing for the tradesman whose services are engaged for the job, to so perform his work, or to do something else to the car, as to ensure its return for further attention in a few weeks' time. This is a scathing indictment of motor engineers in general, and, if true, shows the prevalence of a dishonest practice which assuredly requires stamping out. Not every car owner is possessed of sufficient mechanical knowledge, even whero aided by a book of instructions issued by the mater of his car, to know exactly how any defect which has arisen in the mechanism should be rectified—many self-styled experts appear to fail in this respect it* is not always practicable, as Mr. Dukes suggests should be done, for <an owner to supervise the work being done to his car at a garage, for the simple reason that he cannot, wait until it is put in hand. To my mind, the surest way to guard against such chicanery as Mr. Dukes' letter exposes, is to buy your car from a firm which specialises in the agency for that particular make, and to see that, when anything goes wrong with it, nobody ehie but the firm from which it was bought effects repairs. It is the aim of the holder of any oar agency worth-having to maintain the reputation for the reliability of the car whose maker ho represents, and to this end he will see ilhai defect arising from ordinary wear and tear are as few and far between as possible. Sharpers and dishonest persons there are in all trados, whether more proportionately in the motor business than in any other I am unable to say, but the above, even Mr. Dukes mosv concede, is an illustration of a case in which honesty is the best policy, and its adoption may be taken for granted. Sequitcr. USE GOOD LUBRICATING OIL. You no longer have to subject your motor to the tender mercies of the blowtorch, oil men tell us. Good oil, they say, is the ounce of prevention which is worth all the " cure" there is! because " cure " is expensive when carbon is the disease. Any oil burns; it cannot help it under the heat of your motor's combustion. And when oil or petrol burns, carbon is formed carbon; soft, fluffy soot. You get about as much of it with good oil as with bad. And true carbon is not injurious, unless held in < the cylinder. It blows out through the exhaust. It is the hard flinty stuff that has to be burned or chipped off—the familiar c&xbon deposit which causes so much loss of power, engine knocks, trouble and expense. That which most of us call hwrd carbon is really a mixture of road dust, metal scrapings and carbon soot (comparatively j little of the latter). This mixture is : embedded in a gummy substance left by j poor oil when it burns up under motor I heat; and bakes into a hard flinty mass on i cylinder head,- valves and piston — the familiar carbon deposit. You can see that your oil controls carbon deposits. , Poor oil causes them; good oil—a pure, "straight run oil— j prevents them. ! All lubricating oils and petrol are petro leum products. Crude petroleum is distilled and from it come naptha benzine, petrol, kerosene, and then oils. For years it has been the practice of refiners to take from crude oil as high a yield as possible of petrol; and not more than two types .of-. light lubricating oils. To get heavier types —above " light " . and " medium," they mix these light oils in varying , proportions with " cylinder stock. ; , . • Cylinder stock," is the thick, tarry residue left in. the still after paraffin base crude is refined; and takes its name from its use for ~ steam cylinder lubrication. It is full of paraffin. Under the high temperature present .in' the running motor a compounded oil decomposes. < The light oil burns off, leaving " cylinder stock. It is this sticky smear of cylinder stock " which is responsible for nearly all carbon troubles. it sticks to valves, pistons, and cylinder walls; it collects carbon, soot, particles of metal and road dust, which come in with the air through the carburettor. It quickly bakes hard, and there is your full fledged carbon deposit. Pre-ignition, sticking valves and loss of power are only part of the troubles " cylinder stock " "in your oil can cause you.

For the best results in satisfaction and economy, you need a pure oil properly refined. It is possible to procure an oil which offers as many as five or sir. types of absolutely pure,- wholly distilled lubricant; not compounded with "cylinder stock."

Engineers declare that lubrication is the most important factor in the satisfactory performance and economy we get from our automobiles. Oil * makes or breaks a motor, they say; lengthens or shortens its life.

A pure, wholly distilled oil spreads its film over cylinder and piston, eliminating friction. It seals up the space between cylinder wall and piston ring, keeping compression and power where they belong. And above all it burns clean; leaves no gummy residue to gather dust and soot and form carbon. Be sure then that you pick a good oil of the right type for your motor; and then slick to it. It is motor life-insur-ance, repair insurance, and general satisfaction insurance. You will never regret the care used to make sure of getting u uoaA Lnbricana.