MOTOR COLUMN

Taranaki Central Press, Volume IV, Issue 350, 3 February 1937, Page 3

MOTOR COLUMN

CARE OF THE CAR

, Hints For Careful Owners. ECONOMY. Economical operation is, as it should be, the aim of most motor-car owners. The fuel bill is one of the most important points of attack, but there is a limit to the degree to which the mixture may be weakened. If carried too far it will defeat its own purpose. More intermediate gearwork is called for where formerly top gear could be used, the motor tends to overheat, valves and seats burn, and poor acceleration is experienced. Idling is unsteady and faster. On the other hand, there are firms who are specialising in tuning for economy, and to whom numerous motorists are indebted for a ponderable decrease in fuel consumption. A smaller main jet, pump or acceleration jets, readjustment of the float level, and resetting of the choke are a few common cures for petrol extravagance. * * * OIL CONSUMPTION. Overhead valve motors are apt to suffer high oil consumption due to the passage of an excessive quantity down the intake stems, assisted by suction. This trouble may often be alleviated 'by reducing the flow to the valve gear. Closing off the supply by fitting- a restrictor, partly flattening the supply pipe, or reduc-

ing the engine oil pressure are methods which might be applied, as found suitable. Worn valve guides and stems, excessive oil feed to the stem contacting end of the rockers, faulty valve seatings, insufficient tappet clearance and weak valve springs are worthy of consideration as possible causes. It has been known for oil to leak down between the valve guides and their bored location in the cylinder head. See that the valve cover is well vented. * * * LOOSE STEERING. A loose ball joint in the steering linkage is a frequent cause of wheel wobble. Springs break or lose their tension, and should be renewed. Keep the pinch bolt of split type drop arms, or the large nut of the taper* mounted type well tightened. Pressed steel shackles are sufficiently flexible to permit slight adjustment. Loo-seness causes rattling, and no more clearance need be allowed than is necessary for free action. * * * IDLING SPEED. It is very nice to have the motor adjusted to tick over at a very slow and even rate, but there are numerous limiting factors which act against super-tuning in this respect. A stalling motor is a source of annoyance in traffic, and where some wear of valve stems and guides has.taken place, or air is finding entry at any other point, the motor which is tuned for slow running will usually cut out intermittently. Use the air screw and throttle stop screw to adjust the motor for sufficient speed to maintain gas flow from the carburettor and to store up energy in the flywheel. Correctly adjusted, the idling speed will drive the car at 5 to 8 miles an hour in top gear on a level, smooth road. Retard the ignition part way for best slow running, where a manual control is provided. * * * WORN BEARINGS. Ball and roller bearings, unless applied to constantly revolving parts, have the habit of grooving or forming holes in the races. For this reason it has been found that the steering of certain motor vehicles, including trucks, will become stiff where the oscillating thrust of the king pins and swivels is borne by ball or roller bearings. Actually the front of the car has to be raised when you steer to left or right lock, so it is obvious that when the thrusts are grooved

easy steering is unobtainable. Also for adjusting the steering box worm bearings, similar stiffness on the locks is experienced, and the ball races frequently fail and break. The most permanent remedy is to instal new bearings, and keep them thoroughly lubricated at all times. * # * SPEEDOMETER SYSTEM. Look aft,er the speedometer and drive system. End connections must be kept tight; they tend to loosen in service, and the result is rapid wear and breakage of worn gears and cable. Avoid abrupt bends in the cable and casing, and once in 10,000 miles have the cable drawn out and immersed in heavy oil or a light grapliited grease, and replaced. * # * OIL SUMP. It is unusual to find a motor of modern design where provision for speedy draining of the sump is omitted, and a quickly detachable filter as a rule added. Nevertheless, it is recommended, that about every 10,000 miles or so the sump 'be removed and thoroughly cleaned out, thus entirely removing deposited sludge. The working parts of the engine are definitely benefited, and will wear less, due to the purity of the oil in use. Flushing with kerosene is taboo these days, and it is considered a dangerous practice? Oil sump packings should be renewed if at all torn. Tighten sump nuts evenly, and work out diagonally from the centre.