MOTORING

Nelson Evening Mail, Volume LXI, 4 February 1928, Page 4

MOTORING

NOTES FOR THE OWNERDRIVER WHEN OVERHAULING THE CAR CLEANLINESS IS IMPORTANT One of the most important things to 1,0 observed by the amateur in overhauling bis car is cleanliness. If possible see that the car is thoroughly washed, underneath and elsewhere, before starting on the job. Dirty, slimy parts, or parts caked with old grease and mud are not conducive to one’s boat efforts, tending to sloppy work. If the car is reasonably ..clean to start with the work is easier to get at, and there is less danger of getting one’s eyes filled with dirt when working underneath.

It is well to provide for thoroughly cleaning parts before doing anything else. Provide two or three good-sized receptacles for petrol, and don’t he afraid to use it. A few cut-down kerosene tins are good equipment for this purpose. It. is well to keep one of these for cleaning small parts which do not come in contact with sand and dirt, as it can readily be seen that it would not he good practice to wash carburetter parts, for instance, in the. same petrol that had just been used for washing a steering knuckle. Change petrol when it gets very dirty. Petrol costs less than parts, and a little grit in a valve guide may cost more in the end than would lmy many gallons of spirit. It is a good idea to wash engine parts as they are taken off in taking down the engine. Include everything, nuts, bolts, lock washers, and screws, as well as the parts themselves. Get a few cigar-boxes, as well as larger boxes at hand, when taking off each assembly from the engine, and put small parts in one of them as they come off. When the box is full, or when the particular unit is dismantled, wash everything thoroughly in petrol, and put these parts in a clean box. In this way, when you go to make adjustments or replacements, or when you are ready to re-assemblc your engine, you will have good, clean parts to work with; there will be no grit or abrasive matter to get into other parts and possibly make trouble, and you will avoid the annoyance of having to stop and clean parts when you are ready to adjust or replace.

MARK ALL PARTS After you have had your engine down a few times you may be familiar with it, so that such extreme care is not necessary, but before you get thoroughly acquainted with your motor it is wise to keep each assembly in a "separate box. All manifolds and their connections, as well as the capscrews, bolts, nuts, etc., belonging to them, should be kept together. Valves, push rods, valve lifters, Valve etc., should be in another box, and so on. It is very important to be sure just how a part is sot in relation to other parts before taking it off. Take a little time, and get the arrangement thoroughly fixed in your mind, or, better still, ’ mark it. Valves, for instance, if not already marked, should be marked with a punch 1,2, etc.).' If your motor has timing gears bo sure that these gears are marked before taking them off. If it has a timing chain mark the sprockets after turning the flywheel, so that the “intake open” mark, for example, is on upper dead centre. Lay a straight edge from the centre of each shaft, and put a punch mark on or between the teeth of the sprockets where the straight edge rests. Have a pad and pencil handy to make any notations necessary. Of course, this is not necessary when you have a little experience, but it is best at all times to err on the side of extreme care, rather than the opposite.

SHORTENING THE LIFE OF TYRES With a little care the life of motor ear tyres would be of much longer duration. There is the old trick of running into the “frogs” of a street car crossing. This pinches the tyre—both tube and cover—causing a breaking of the fabric walls. It also scrapes quantities of rubber off the surface of the tread. Riding the rails is in itself a bad practice, and one that almost all of us are guilty of at times. This places all the. strain of holding up the car on half of the tyre, tending to break down the tyre walls, especially when the tyres are rather soft. Running smack into the kcrbing and leaving the car so that the kerb “bites” into the tyre, breaking down the fabric and grinding off valuable rubber, is .another common way in which tyre mortality is speeded up. Equally destructive of treads is the habit of scraping along the kerb when parking, or of “clipping” the corners when making turns. Another easy way to break down 'the fabric of your tyre is to park so that one wheel is over a drain. The cross-bars of a manhole or drain cover will press up against the tyre in a way that will raise trouble with the best built tyre. USE OF A MIRROR Every private garage repair shop should possess a small mirror for use «vlicn dismantling, adjusting, or examining inaccessible parts. A mirror enclosed in a strong sheet metal frame and provided with a handle may be so tilted that the piston may be seen through the valve cap opening, or to deflect light into flic differential casing, for instance. It is useful not only for giving an image of an awkwardly placed part hut also for illuminating out-of-the-way. components. The con-tact-breaker, the oil sump level gauge, the hack of the dashboard, and the inside of the petrol tank can all he lighted up by this method. In many cases the soriber marks used for assembling, engine numbers, lines, or centre punch marks can only be seen with the aid, of a mirror, unless one is prepared to do a certain amount of dismantling. PRESSURE V. LUBRICA* TION A long scries of experiments conducted with engines having pressure and splash {pump and trough) lubrication systems have brought into prominence a risk of rapid wear, hearing troubles, and even piston seizure, that attach to the pressure system to a far greater degree than to the splash system. One section of the experiments consisted of “motoring” an engine (driving it by an electrical motor) after certain parts had been cut away, so that observation could be made as to what happened in respect of oil circulation at various temperatures. One suspicion was thus confirmed: that with an engine cold no oil exuded from the big-end and main crankshaft bearings, and that that state of affairs persisted until the oil and the bearings.

wanned up. Meanwhile the pistons and cylinder hur.es had become almost dry, and the eontaet snrl'aees had cumineneed (u ‘•score.” On the other hand, under similar conditions, an engine with splash lubrication suite red no shortage of oil or harm at, any point. Subsequent tests showed that if an engine with pressure lubrication were run under its own power at 1000 r.p.ni. for five minutes, stopped for ‘JO minutes, and tiiat sequence of runs and stops eontinued from three to live times, the combination of lack of oil and formation of rust due to condensation had the effect of aluminium pistons seizing so tightly that they had to he driven out of the cylinders after the engine had been dismantled. The trouble could be remedied, it was found, by arranging for a small but definite quantity of oil to be thrown on the cylinder walls during the starting period. With a splash-lubricated engine no such trouble occurred, the reason being that the clipping of each connecting rod into its trough caused oil to be supplied to the cylinder walls immediately the engine was started.

TOURING SERVICE FOR MOTORISTS IN BRITAIN No country offers the touring motorist such a wealth of wayside interest and romance as Great Britain, and provided adequate instructions are available, it is easy to enjoy unlimited miles of glorious travel with visits to endless points of interest that are linked with the life of early days. In rendering these tours more easily available to the motorist, signal work is being done by the Dunlop Touring Service Bureau, at 4.1 Kingsway, London, W.C.2. Motorists only have to make enquiry at this bureau (giving some indication of the time at their disposal on the part of the country they wish to visit) to receive, entirely free of cost, a complete itinerary of the tour indicating mileages ancl all details of interest on the road. Accompanying the itinerary is a road map, on which the route is shown by a blue line, with sections of bad roads, repairs, etc. marked in red. Information is also furnished on guide books and other relative matters that will heighten the interest and enjoyment of the tour. New Zealanders on returning from a visit to the Homeland speak highly of the splendid work being done by" tlie Dunlop' bureau in revealing much of the beauty and interest of Britain that would otherwise never have been viewed.