THE RADIATOR.

Hawera Star, Volume XLIX, 16 November 1929, Page 15

THE RADIATOR.

STOPS OVERHEATING. LOOK OUT FOR LEAKS. Two kinds or types of radiators are used in motor-ears —namely, the tubular and the cellular; or, as the latter is also called, honeycomb radiator. Sections of a tubular radiator offer interesting studies, it is made up of a great many small tubes- About the tubes ana pressing against them are many thin metal pieces called tins. The purpose of these tins is to conduct the heat away from the tubas so as to cause the water to cool quickly. The fins in turn are cooled by a blast of air drawn through the radiator by a fan, which is usually driven by a belt from a pulley actuated by the engine. ) To keep the engine from overheating I the fan must work properly, and the 'belt must not slip. In time the belt will stretch and must be tightened. I It may be .said that in the tubular 1 radiator the cooling is indirect, tin ] heat being transferred from the water Ito the metal tubes, then by them to I the thin fans, and from them to the blast of air produced by the fan. In the cellular radiator the cooling is more direct, there being no metal tins. The principle of design is to divide the water into thin streams and. give the streams a long passage. Thus there will be a great surface of water in contact with the thin metal, which metal is directly acted upon by the blast of air drawn through by the fan. In short, the water is given a large radiating surface. To-day designers know how to build radiators, and also how properly to mount them, so that they seldom leak because of vibration. Should a leak develop, you should immediately have the radiator repaired by an expert in this kind of work. There are a number of compounds on the market for stopping radiator leaks. If an engine has always run quite cool, these can often be used to advantage, but the wise thing to do is bo have the radiator properly repaired, as by the use of these compounds the cooling power of the radiator is often decreased, sometimes considerably. There may come a time when, due to an accident, a serious leak is made in the radiator, and when an emergency repair is necessary.

The writer believes plaster of paris to be excellent for this purpose. To use put a little water in a clean receptacle and slowly sprinkle in the plaster oi paris, mixing it until it is like soft putty. Then immediately smear into the hole in the radiator- A quite large hole can. sometimes be temporarily repaired in this way. However, remember this is only a repair to be made in an emergency, and when it is impossible to have a proper repair made and you are far from home, and the cost of towing, storage, repair and transportation will 'about equal the cost of a new radiator. Near the top of the inside of tlio filler cap you will find a small pipe. This is the overflow pipe, and is placed there to allow excess water to escape when the radiator becomes too full, due to the expansion of the water when it gets hot. Keep this pipe clean. Sometimes after filling the radiator and making a short run you will see water flowing out of the •bottom of this pipe. This should be so, and is not a leak to be worried about, as is oiten done by people ignorant of the existence of this pipe.