THE MOTOR WORLD

New Zealand Times, Volume XLV, Issue 10432, 10 November 1919, Page 3

THE MOTOR WORLD

VARIOUS NOTES NON-APPEARANCE OF "AFTERWAR" ENGINES. There has been much, talk about tlio wonderful engines that are to appear "after the war," but there is little likelihood that anything embodying notable changes will be seen for some months to come, for the (reason that manufacturers have been too busy in other directions to develop new designs, and present models have stood the most exhaustive tests in this strenuous War work "over there." which would not indicate any very great necesity for a change just now Still, evolution of tho internal combusion motor may be expected to continue in its natural course, and not a few engineers have dreams of future engines of wonderful economy and efficiency. At a mooting of automobile engineers not long ago one of them said: "The internal combustion engine is understood in general, but in. fuel and efficiency problems special attention must be focused on at. Our engines are not efficient. We must design engines that will use fuel more economically and not throw away 40 per cent. of its thermal efficiency through the water jackets and 30 per cent, through tho exhaust, as is done to-day. It would greatly interest many of us to have some definite suggestions as to how these things are to be effected.' j MOTOR-CYCLE'S VALVE LIFTER. The modern three and motor-cycle being no longer dependent on the exhaust valve lifter as,a means of control and merely requiring; the device to facilitate starting, lias introduced a distinct tendency on the part of designers so to arrange the valve lifter that it is operated by the initial .movement of tho kick-starter pedal. In a recent British patent thero is a lever, pivoted on the gear box, which operates the Bowden wire of the valve lifter through the action of a cam formed by milling a flat on the starter-pedal spindle. The lifting device proper consists of a bell crank lever pivoted on aplate attached to the crank case; the shorter end of the lever carries a, small rocking arm, one end of which, lies under the catch on a small trip lever also attached to tho bell crank. The same movement which raises the valve also causes the lower end of the trip lever to slido along an inclined plane forming part of the crank case attachment plate, and after the correct length of travel the catch moves past the end of tho rocking arm, thus allowing the valve to drop suddenly. Several alternatives and simplifications are suggested, perhaps the most interesting being a method of operating the Bowden control by means of an eccentrio instead of a cam on the startor spindle. LATERAL CLEARANCES. In those parts of any machine whioh have a slight back and forth as well as rotating motion, as an automobile crankshaft, tho end "lav sliould always be sufficient to prevent any possibility of restricted action to tho piece, otherwise connecting rod brass reajustment wearing out of parte or other unlooked for difficulties may result in heating trouble. Thero is no practical virtue in outting clearanoes too fine, although there are undoubtedly situations where the minimum amount of clearance must be looked to. In many cases adjustments could bo made to rectify clearance discrepancies, but oven if this is possible it Is not a procedure to be recommended because! any adj etment that has bain given to the part, is there ftr some other definite reason, and the elimination of this may absolutely upset everything when tho need for legitimate adjustment has to bo carried into effect. In most cases these existing allowances cannot be tampered with without creating trouble wnd a depreciation which may involve considerable risk in the liability of injuring the working parts. WIATCH THE DISTRIBUTOR. Car owners should not forget that one part of the battery system which needs attention is the distributor head. When soot forms on this part it often enables the current to pass across from one terminal to another, with pre-ignitlon as n result. The track of the distributor head should be kept clean and be touched up from 'time to time with a kersone soaked rag. This will prevent its becoming dirty and will keep tho motor button from sticking and cutting. ELECTRIC TYRE PUMP NEEDED. Electric installations on the modern car, especially those of American origin, are becoming so much more complete and reliable than formerly that an English writer expressed surprise that no enterprising firm has produced a small elec-trically-driven tyre pump. There are one or two good makes of mechanical tyro pumps on the market which are suitable for email cars, but he has not yet found a simple device for blowing up automatically large car tyros. He believes that it should not provo an impossible task to design on electrical compressor which oould be carried separately like a jack and connected up when required to a tilug conveniently situated either on the switch-board or eomo other handy place in the circuit.