MOTORDOM

Sun (Auckland), Volume II, Issue 604, 5 March 1929, Page 6

MOTORDOM

THROUGH THE NORTH I A.A.A. OFFICIAL'S REPORT j “During the recent trip of the north we travelled about SSO miles, visiting all our agents and inspecting practically all new road formation and works carried on under the Main Highways scheme. The impression we have gained is that the Highways Board is alive to the requirements of modern traffic and is providing good grades easy bends and, above al, good visibility,’’ states the report recently issued by J. Park and Mr R. E. Champtaloup, two A.A.A. officials, of their tour round the North; “At spme works where construction was completed a little time ago the formation is not up to the standard being adopted to-day. One particular point we noticed was in regard to the bridges which are now being constructed. On the Mangamuka-Rangi-ahua highway, while an excellent surface has been provided, narrow onecar bridges are being built, and we strongly recommend council to urge the Highways Board to make provision for two-way traffic on all pending structures. “Heavy construction work is being carried out between Okaihau and Rangiahua. There are three railway crossings and, after inspecting the plans of the bridges so far as they have been completed, we are of the opinion that sufficient consideration has not been paid to the road-user. The bridges, while they will not exactly be at right angles, are only skewed to an angle of 30 degrees. “Considerable progress is being made in the construction work between Puhoi and Maungaturoto. AVe made numerous inquiries and in almost every case learned that the men were on contract work. The old notorious Turntable Hill is now out of use and traffic is proceeding along the deviation. “Between Kaikohe and Whangarei a certain amount of work is being done, but the old clay surfaces which are not yet under formation are very disappointing, and we suggest that the Highways Board be requested to secure an improvement by having the surface graded. This naturally does not apply to any portion of the road where new work is in progress. “Some years ago the Highways Board notified this association that the section between Kaikohe and Rawene would be completed on the county council supplying its share of the money. We were informed by the county council that it paid this money to the board some time ago, but we understand that the board does not propose to complete this gap immediately. This stretch* is a very important one, and we recommend council to strongly impress on the board the importance of providing an all-weather connection immediately. “Just to the western, .end of -this clay gap there is a small metalled hill, round which a deviation will eventually be constructed. The condition of this short hill almost defies description, and is a serious reflection on those responsible for the maintenance of this important highway. We suggest that very strong representations be made to the Main Highways Board in this respect urging reasonable maintenance.”

? fey— \ HEADLIGH'

Gear Changing Obtaining a Lower Gear It is important to bear in mind that in the gearbox there are two sets of pinions on two shafts (the main and the secondary). The main shaft runs in a direct line between the engine s»nd the back axle; the secondary shaft runs alongside it. These two shafts are connected by what are known as “constant mesh pinions.. The secondary shaft carries a number of fixed pinions, and the main shaft sliding pinions which engage with them. By meshing one of the sliding pinions on the main shaft with the corresponding one on the layshaft, the variation in gear is obtained. It is very important to bear in mind that these two shafts may be rotating at, different speeds at the moment of changing gear. Not only that, but, owing to the different sizes of the pinions, their speed at their peripheries may be very different.

CAR A NECESSITY OPINION OF AMERICAN WOMEN Of all the necessities of life, American farm women rank the motor-car first. Running water in the kitchen comes second, a sink third, telephone fourth, and radio set fifth. This was revealed by answers to 40,000 questionnaires sent to American farm women by the Federation of Women’s Clubs. Nearly four-fifths had cars, onefifth, radio sets, over half telephones, and less than one-third had running or pumped water at kitchen sinks. Questionnaires sent to 4,101,581 families in the United States covering both city and rural areas revealed than in 1926 56.5 per cent, of homes had telephones, 55.7 per cent, motorcars, 46.2 per cent, gramophones, 40.4 per cent, pianos, and 24.1 per cent, radio sets. In communities of less than 1,000 of population the proportion of families owning automobiles reached 60 per cent. In cities with over 100,000 inhabitants, 54 per cent, of families had motor-cars.

To bring a pinion which is stationary. or only rotating at a slow speed, into mesh with one that is spinning very fast, will set up that jarring, crashing sound associated with bad gear changing, because the teeth of the pinions, instead of meshing, scrape violently against each other, which is very destructive to their edges. Now, the speed of the secondary shaft is governed by the speed of the engine (from the engine, through the clutch to the constant mesh pinions); while the speed of the main shaft is governed by the speed of the back axle with which it is in direct connection. The main shaft is not solidly connected with the power shaft, but only when top, or direct gear is engaged, the connection then being made by a “dog clutch.” It is difficult, except by using the brakes, to govern the speed of the main shaft. It is very easy by means of the engine, and when the gear lever is in neutral, to vary the speed of the secondary shaft. Thus, with the gear lever in neutral, and the clutch in, we speed up the secondary shaft by opening the throttle or we decrease its speed by closing the throttle.

FINDING ENGINE TIGHTNESS Whether the engine of the new car really is “tight” cannot always be told from driving it. If the gears are stiff the impression may be gained that the engine is tighter than it is. Even the strangeness of the new car often makes it seem as though the engine wasn’t ready for even moderately fast speed. A more satisfactory way of finding out the truth about the engine is to make what is known as the “stopping ; test.” While the engine is running it is suddenly switched off and its be- ; haviour observed. [ If it stops instantly its bearings are ! very tight. But if it makes a revolu- ' tiou or two the indications are that ' the motor is fairly free, j The higher compression now used in - engines prevents them from rotating s more than a few turns after ignition i is switched off. even if bearings are . fairly free. This must be taken into account