MAKING MOTORS MIND

Timaru Herald, Volume CXXV, Issue 18629, 26 July 1930, Page 10

MAKING MOTORS MIND

HELPFUL HINTS FOR MOTORIST IBy Mr Max Wall. Service Manager ol General Motors, New Zealand, Ltd.] Most electrical circuits in an automobile are of the type known as single wire, grounded circuit-systems. The ground connection should be examined regularly and tightened, if loose, to avoid possible difficulty in the electric system. A wire connects one of the battery terminals to the instruments and lamps, the other battery terminal and one terminal of each instrument and lamp are grounded to the frame and metal parts of the car, forming a complete circuit.

The oil filter cartridge, which removes carbon and gritty substances from the engine oil, should be renewed every 8000 or 10,000 miles. The cartridge becomes clogged with sediment and is usually ineffective after this amount of mileage. Any water or dirt which the benzine filter has removed from the fuel may be seen in the glass bowl. It is advisable to inspect the filter occasionally and remove and clean the bowl when water or dirt is visible.

The riding quality of a light roadster may be improved by carrying added weight. One method is to keep the petx-ol tank as full as possible. Benzine weighs around seven pounds to the gallon and, being carried at the real- of the car adds considerably to the riding comfort.

The presence of oil in the water of the radiator is an indication of an over-lubricated pump shaft bearing or a leak between the compression chamber and the water jacket. In the case of the latter, it is usually the forerunner of a blown-out cylinder head gasket and should be attended to without delay. The cylinder head bolts may require tightening or the gasket replaced.

When wiping the oil from the bayonet gauge that measures the oil in the crankcase, it is important that no lint or thread remains attached to the gauge when it is inserted in the crankcast.

Although the carburettor is comparatively simple in its mechanism, the car owner should not attempt to alter the adjustment unless he is experienced in carburettor adjustments and is familiar with the characteristics of the eogjne. It is better to send the car to | the service station. Many ills of the' engine that are laid to the carburettor are frequently caused by sowething else.

Springs are constantly subjected to strains. Spring bolts and clips occasionally need tightening. Too much looseness of nuts on clips and U-bplts may result in leak breakage.

fever-heating may be the result of various conditions, one of the most frequent of which is insufficient water r in the cooling system, traceable to leaks at loose connections, leaks in the radiator core or pump shaft packing. Another cause is poor circulation due to obstructions in the water passages such as sediment scale formations, flakes of softened rubber from deteriorated loose connection, etc. Loose fan belts are also a source of trouble. In some engines the fan shaft is also the water pump shaft and if the fan belt is loose, both water and air circulation is affected. An investigation to determine the cause of over-heating include the ignition timing, amount and condition of lubricating oil and the carburetter and brake adjustments. When the ignition is irregular and spark plugs are known to be in good condition, inspect the spark-plug cables. Cracks in the insulation, caused by high temperatures and escaping oil, permit the high tension current to escape before it reaches the spark plug, if the cables are near the cylinder block or other metal parts of the engine.