SOME IGNITION TROUBLES.
Page 31
If you've noticed an error in this article please click here to report it so we can fix it.
Useful Suggestions from Our Driver and Mechanic Readers.
/TROUBLES with the ignition are' I usually more irritating than serious. They may be generally avoided by that process which is largely known as effecting a stitch in time. Such a stitch is that which is in a way, suggested by " Rif." in ills letter &Scribing how high-tension wiring may •best and most economically be renewed, or, at least, overhauled, and renewed wherever necessary and with the minimum of trouble and expense.
The accompanying sketches are chiefly of interest, in those cases which are, after all, most likely to occur, in which it is not. necessary to renew the wiring from end to end, but where the process of overhaul reveals that certain parts of the insulation of the wiring are so worn, burnt, or chafed that the renewal of parts of the wiring is likely, if not to cure existing troubles, at least, to tend to the avoidance of breakdowns in the near future.
Figs. 1, 2, and 3, for example, show how the junction between the existing wires and the new pieces may best be effected. The insulation as may be seen, is stripped off for I: in. or 14 ins. and the projecting wires crossed, twisted and finally wrapped one round the other, so as to ensure a maximum of electrical contact. The joint is then carefully wrapped with a generous supply of insulating tape, care being taken that it is not so placed that it comes into contact with any metal portion of the engine at any time. Indeed, it is a good rule to endeavour so to arrange the wiring that its contact with metal is as little as possible, particularly where that metal is likely to be hot. It is quite easy to make a suitable carrier from fibre or wood, which will carry the wires easily and safely, keeping them out of harm's way. Such a fitting, too, gives the top of the engine a much neater appearance than that which obtains when the wires lie more or less loosely about the tops of the cylinders.
Cheap brass eyelets for use wherever the wires have to be attached to terminals are procurable from most accessory stores, but are not actually indispensable, as a good, permanent ring may be made from the ignition wire itself, as shown in Figs. 4 and 5. Commence by cutting back the insulation from the ends for a distance of about 14 ins. This is accomplished quite easily by cutting the insulation right through with a knife at intervals of about in. The pieces thus separated may then be twisted off one by one, leaving the wire bare and quite clean for future operations. Having got so far, double the exposed wire over itself in the form of a loop, as shown in Fig. 4. Twist the loop, when the end will tighten itself, and when complete will appear as illustrated in Fig. 5. An eye properly made according to these instructions will not fray, but will keep in good shape for quite a long time. When going over the wires in this way it is best, wherever possible, to refit one wire at a time. This procedure will frequently save the trouble of checking the
In the event of a sparking-plug nut or spring terminal being lost., a new One may be made from a piece of hard brass i wire, bent as shown n Fig. 6. The eye should be a little smaller than the outside diameter of the screw on which it is to fit.
When refitting wires to the magneto, trouble is often experienced in connection with the small screw which holds the strands of the wire in place in the magneto terminal. These screws are generally quite small and are located at the bottom of holes in the insulation
material. The holes are generally so small in diameter that the average screw
driver will not enter. In such circunrstances the tang of a small, flat file, if shaped as shown in Fig. 7, will make an excellent, tool. The tang will enter the hole quite nicely, while the flat of the file affords an excellent grip for the hand. Will " R.H.," to whom we award the 15s. prize, please send his full address?
A. useful tip is forwarded by " of Raynes Park, in connection with the cleaning of sparking plugs. The usual processes, he states, " scraping with a penknife," or "filling the interior with petrol and burning it out," do not always afford the success which is expected. The oil, burnt or otherwise, which causes the plug to short, usually bridges the insulating material al a point within the body which is out of convenient reach of any scraping tool, as well he being in most cases, quite out of sight. The best method consists in boiling the plugs in a solution of caustic soda which will dissolve all oil and carbon, leaving the plugs clean and bright both inside and out.
A few ounces of caustic soda crystals should be obtained and dissolved in water in the proportions of about 1 lb. to one gallon of water. Place the plugs in a tin and cover them with the solution, which should be brought to the boil and kept there far a few minutes. Afterwards the plugs may either be taken out at once or left in the solution to cool, but in any case they must, immediately on removal, be transferred to a vessel f clear water. If this be not done, a layer of the impregnated solution will adhere to the plugs when they dry off, and it is not a beneficial ingredient to havein the ignition system of any engine.
A final rinse in clean water and a brush down with petrol completes the operation, and when the spirit has evaporated the plugs will be found to be practically as good as new, on the understanding, of course, that there are no other defects, such as cracked porcelains or broken insulation; which such a process &mid not possibly cure.
This method of cleaning plugs is equally applicable to either porcelain or mica-insulated plugs, and has, in addition, the advantage that any number of plugs may be successfully treated at one operation.
With regard to sparking plugs in general, it is not usually recognized that it is not advisable to use any but a box spanner when fixing them in place. With an ordinary spanner the pressure on two opposite sides of the plugs plates an unnecessary and often harmful strain on the insulation, which, particularly in the ease of porcelain, may cause it to crack.