WHAT A CAR TELLS

Hawera Star, Volume L, 29 November 1930, Page 12

WHAT A CAR TELLS

KNOW YOUR MOTOR’S VOICE, INVESTIGATE STRANGE NOISES. Although a motor car cannot speak it can give the observant owner-driver a lot of useful information (says a writer in the “Observer”). “Know your motor’s voice” is a slogan which every motorist should take to heart. The first thing the owner-driver should do when taking over a car, whether a new one or a second-hand, is to accustom himself to the gentle rhythmic purr which is the only noise that will be heard when a properly tuned engine is running well within its power. If this be done, any alteration in sound, no matter how slight, will be noticed at once, and it will be realised that something is amiss. To continue running the car when a strange noise is heard without at. once discovering its cause is likely to lead to trouble. However slight the unaccustomed noise may be, it indicates that something is amiss. It may be only a veryslight “knock” when the car is called' upon to take a gradient under load;

this indicates that the spark is ad-1 vanced too much or that the engine! needs decarbonising. A thud will i suggest that; a big end is worn and needs taking up. Spasmodic firing will show that the carburation or ignition is at i'ualt. In a hundred other ways the driver will know for a certainty that some part requires adjustment. Whenever any untoward sound be heard the cause should be discovered instantly. It may prove to Ue only T a trifling matter. On the other hand, it may mean a serious breakdown if not attended to immediately. Unless a proper system he adopted, tracing a fault in the engine or transmission may- be rather a lengthy business. All maladjustments which cannot possibly be at the root of the trouble should first of all be eliminated. This will save much time. Then take into account whether the fault be local or general; whether the trouble lias developed suddenly or whether it has been manifesting itself for some time.

If a knock, for instance, develops in one cylinder it cannot obviously be due to ignition or carburation faults, since if either were the . cause all cylinders would be affected in the same manner and to the same degree. A sudden loss of engine power cannot be due, say, to a weak exhaust spring, low compression, or too small a jetopenium in the carburettor, because the two former faults do not develop suddenly, while the last-mentioned is a constant factor. In the same way a gradual loss of power cannot be due to any mechanical defect, as such defect shows itself suddenly.