THE WINTER START

Evening Post, Volume CIX, Issue 144, 21 June 1930, Page 26

THE WINTER START

WHY IT IS DIFFICULT

'i hi; kngim: and olaks

■ iSJowthat eoidj weather is setting jii'the-'new.motorist is pipb'ably meeting with a good" many H: 'unexpected troubles. Probably ho wiilnotiee. that if-he.- engine does not respond so readily jo, tine .starting motor in' "the morning, and-greater use has to be made of the air.straggler in order.to. get the'engine to fire. Again, in some cases when the engine has been^ successfully started a little difficulty,may be experienced in moving the gear lever so as to engage first,, speed without causing a grating noise.'.,! ~, ..•......'■: r.. ... 'The reason why the engine does not start so readily is a twofold one, for the lower temperature results in the oil in the", engine'1 becoming more viscous, so that it requires a greater effort xfrom the starting motor to turn

the engine round, and at the same time the petrol in. the carburrettor does not vaporise so easily owing to the lower temperature. The reduced speed at which the'starter is able to spin the engine also has an adverse effect on carburation.

An alteration to the carburettor may also be called for if the weather bocomes really cold, and in some cases su adjustment is provided which merely needs setting according to the maker's instructions. In other cases the slow running jet may be provided with an adjustment, which will only need to be-altered very slightly, while in some carburettors it may be advantageous to fit a slightly larger jet for cold weather'use. As the carburettor manufacturers: issue very informative booklets dealing with. their particular instruments, the instructions given should be carefully read and carried out.

As the difficulty, mentioned, in engaging first gear will only be encountered if a plate clutch running in; oil is fitted to the car, it is fairly obvious that the reason again lies in the oil becoming thicker with the fall in temperature. As a general rule the trouble should'not be serious, and it may usually be overcome by throttling the-engine down to a .tick ov<%r at its slowest speed, disengaging the clutch, and carefully "feeling" the gears as one endeavours to bring them into mesh, a sharp decisive movement of the lever must be made when the right moment arrives. If a grating sound cannot be avoided by thisMnethod, adopt the same x>rocedure, but. try engaging reverse gear. This may. engage more easily; anfcthen the gear lever can be pulled- smartly back into the. first gear position- without difficulty, the clutch of course'being held out meanwhile..

In very persistent cases- the clutch may be freed by the following method.When the engine has warmed up sufficiently to ensure easy starting, switch off, engage first gear, depress the clutch pedal, and hold it down while the engine is started again.

As the oil in the gear< box will also be affected by the lower temperature, it will be found that the gear lever does Hot movo so easily until. the car .has been on the road a sufficient time for *^c oil to have warmed up. It is hardly necessary •to use thinner oil in the gear box, however, and no real difficulty should be experienced if the driver bears in mind the fact that the oil offers more resistance to the gear wheels and that, therefore, these tend to slow up more rapidly when ,an upward change is made. In starting off therefore in the morning on. a cold day the upward changes must be made a little —■ sometimes a great deal —morn quickly than usual. , CONTROL OF COOLING SYSTEM. Even if a lighter grade of oil be used in cold weather it will be found that when-the engine is first started up the pressure recorded by the oil gauge is much higher than normal. As the engine warms up the pressure.will gradually! drop as the oil in.the. sump also becomes heated. While the oil is cold and the x>ressin 'C recorded on the gaugo is very high the engine should not bo run at all quickly; the cold, thick oil may not be reaching all the various working surfaces in sufficient quantity, while there is also danger of damaging the gauge.

-Naturally the cooling system is also considerably affected by lower temperatures. Many cars have a thermostat jjjrtejjvjtt ; £he> Jippg^ connection, %q the

radiatoi.so that tho tlow- of wu.tor. from the,.'cylinder jackets to . the radiator is restricted while-the engine is .cold. This results ih: the engine warming up fairly rapidly,, but it must not be "forgotten that in such-eases, the radiator does not warm-up rapidly. ' :.'.''

When radiator shutters are fitted the cooling system as a whole is, of course, protected, but if the shutters are under tho control of the driver, and are not operated automatically by a thermostat .care must bo taken to watch the' radi-ator.'thermometer.-so" that, the shutters may.be opene'd'-to the necessary-extent .beforo'-the water.is brought to boiling pbhiK'"'''-"' ■ . '•-'■''.