Page:Motors and motor-driving (1902).djvu/207

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THE CAPRICES OF THE PETROL MOTOR
175

sparking plugs sucked under the inlet valve, where they have stuck or gone into the cylinder and even through into the exhaust silencer.


FITS AND STARTS

If a motor nearly stops and then goes on again, it is generally due to temporary starvation of the carburator. There is probably some water, oil, waste, dust, asbestos, dirt, or deposit of some sort at the ingress of the spirit, which, however, sometimes frees itself. To avoid these troubles petrol should never be poured into the tank except through a funnel fitted with a very fine gauze strainer or a piece of muslin. I have known a little particle of matter dance about in the mixing chamber, and once in a way it would lodge on top of the spray-nipple for a time.

It should be remembered that air must always find an inlet to the tank in order that the petrol may flow out freely, and considerable difficulty has been caused by the tiny vent-hole which is drilled in the stopper of the main tank becoming blocked up by some dirt or an overcoat lying on it under the cushion. It may happen that air can get to it when you are starting up; then when you sit down on the cushion the hole becomes air-tight and the engine gradually stops.


MOTOR WILL NOT 'PULL' WELL OR MISSES FIRE

We will treat this malady under the following headings:—

A. Ignition.

B. Compression.

C. Carburation.

D. Too much oil.

E. One cylinder will not work at all, and

F. Irregular missing.


A. Nothing is so annoying as to drive a motor which is continually missing fire or has a 'fit of the slows.' The fault is usually with the ignition—the platinum tubes are not hot