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Show AUTO LESSON NO. 69. Ford Ignition Troubles. The ignition system of the Ford car varies greatly from that used on all other makes of cars. The Ford system requires a coil for each spark plug, and the spark is one of great frequency; that is, there is really a great number of sparks at the plug, while with the distributor system, only one coil is required, re-quired, and there is but one single spark at the plug. I might say, however, that a few makes of distributors system use a vibrating vi-brating coil with a separate battery for that is necessary is to connect one wire from about five cells in series, to the metal of the car, say the transmission cover, and the other wire to the vacant binding post A, as shown in the illustration. illus-tration. The mistake of connecting the battery to the magneto binding post, B, is often made. , Doing this will probably prob-ably weaken the magnets of the mag neto. If the vibrator points of the coils are burned or poorly adjusted, starting will be made more difficult. It is a good plan to watch them, especially in cold weather. The magneto contact will often cause Cry CelX starting, but only one coil. This will be found to be the case on some of the Delco systems. Let us see how to go about hunting for the cause of trouble in the Ford svstem. First of all we must know what the circuit of the current from the source, through the various units, is. This is as follows: The current is generated by the magneto, mag-neto, which is built into the flywheel, from which it goes to the magneto current collector plug, called the magneto mag-neto contact, from there to the magneto mag-neto terminal on the coil box, thence to the switch, then the buss bar, by which it is distributed to the four coils. From each of the coils it goes through the vibrator and then by a wire to the commutator, or timer, and then through the metal of the engine to the primary wire attached to the timer and so through this wire back to the coil. In the event of the engine failing to start, or stopping suddenly, because of lack of a spark, we must first determine deter-mine which units in the system and which wires are common to all four cylinders, as if the unit or wire is connected con-nected to one cylinder only, its failure would onlv cause a miss in that particular par-ticular cylinder. We find that on y the magneto, the wire to the magneto terminal on the coil box, the switch and the rotor of the commutator are common com-mon to all the cylinders. Thus for sudden sud-den stopping or failure to start these are the units which must be investigated. investi-gated. The magneto seldom gives trouble if not abused. Sometimes, however, wires from a batterv are incorrectly connected con-nected to the system so as to draw the magnetism from the magnets. This means that magnets must be remagne-tized, remagne-tized, or what will often prove to cost no more, a new set of magnets installed. in-stalled. The voltage generated by the magneto mag-neto varies "with the speed of the engine, en-gine, and at cranking speed is extreme-Ty extreme-Ty low, sometimes not being sufficient to start the engine. For this reason it is a good plan to install a battery for .ft; This can be easilv done, as all trouble by not making proper contact. As a rule, cleaning is all that is necessary. neces-sary. The switch will also sometimes cause trouble by being short-circuited or not making contact. This, however, is not often the case with the later models, though with some of the earlier models it was often so. Congealed oil or water in the commutator commu-tator will cause hard starting and sometimes some-times failure to start. Again cleaning is the remedy. A way to tell if the magneto, switch or commutator is the cause of the engine en-gine stopping, is to take the magneto wire off tho binding post on the coil box and to substitute therefor a wire from a battery of dry cells (the house electric bell battery can be borrowed), I the other battery wire being connectea to the ground. If the engine starts, the magneto, magneto contact, or magneto mag-neto binding post, is at fault. If the engine does not start, take a wire off the commutator and touch it to the ground. If a coil buzzes and there is a spark, the commutator is to blame; while, if the coil fails to buzz, then either the vibrators are not properly set or the switch is at fault. A fault of the vibrators, commutator, commuta-tor, wire connected to the commutator, spark plug or spark plug wire, will cause a miss in the engine. The first thing to do when the engine en-gine misses is to find which cylinder is missing. To do this hold down the vibrator vi-brator points one after the other. The one which causes no change in the running run-ning of the engine is connected to the missing cylinder. Having'determined which cylinder is missing, change around the coil with another coil. If the miss follows the coil, then the coil, probably its vibrator vibra-tor points, is at fault. If, however, the miss continues in the same cylinder, then the coils are all right, and can be forgotten, the fault being due to the spark plug, or its wire, or to the wire going to the commutator, or to the commutator. com-mutator. The above assumes, of course, that the other two essentials, namely compression com-pression and mixture, which are necessary neces-sary for the proper running of the en-, gin'e, are all right. To tell if the spark has failed, take out a plug, lay it on the engine with the wire attached, and crank the engine. en-gine. If the ignition is all right, there will be a spark at the plug, and eithe compression or mixture is at fault, while if there is no spark, the ignition is at fault, and the other two essentials can be assumed as being all right. |