How To Drive A Motorcar
A Key To The Subtleties Of Motoring

TROUBLE WITH THE MAGNETO Some Simple Ignition Difficulties If, after the carburetter has been duly doctored, the car is still obstinate, as a first step remove the main earth wire from the magneto, and—have another swing. If this proves successful it is reasonable to assume that there is something faulty with the switch itself, or that there is a shortage in the switch wiring. If so desired, the car can now be run just as ordinarily, except that one has not got a switch in operation, so that the engine must either be stopped by means of the throttle or the wire replaced and the engine stopped through the medium of the switch. It is perhaps well to rule out of court a common fallacy : absolutely no harm will accrue to the magneto by using it with the main " earth wire (it should be actually “ frame ” or switch wire) detached. It is just worth recording that if one finds the refusal to start up to be due to some part of the engine’s elec- trical appurtenances, one should try the switch in the off position—in other words, in exactly the opposite position to that which is used ordinarily for starting up. It may just chance that there is some defect in the switch itself. Admittedly, it is not often that this is the case, but the writer well remembers the great consternation of a certain well-known motorist, who had spent a great time in trying to start up his engine, and after pooh-poohing the idea, reluctantly allowed a friend to swing it with the switch, in the off position. At the first pull the engine started quite easily, but as the owner’s only comment was far more expressive than useful it is not advisable to record it. However, the fact itself remains that just on an odd occasion the switch may so misbehave itself as to be “ on ” when it is in the off position and vice versa. If these simple little first-aid remedies are not effective then one must seek a little further afield for the trouble. Further Electrical Adjustments Any continued inability to start when once traced to some portion of the electrical appliances must then be sought for in other directions. First of all have a 43