Magneto Impulses.—As the magneto gives out impulses of certain intensity at each revolution, which impulses are designed to actuate the sparking mechanism at certain definite periods, it is obvious that the contact breaker must be properly set.
Timing the Magneto.—This is what is called timing the magneto, and it is one of the things necessary to observe, and to be able to adjust, if it is found that, for any reason, the disk, or the wheel of the contact breaker has turned on the shaft, as will sometimes be the case.
All mechanism of this kind should be “spotted,” that is, have punch marks on the disk and shaft so that it can always be put back to the proper operative position, or nearly so, and thus save the time and labor required for retiming.
In general, however, it may be said that the magneto is one of the mechanical elements, which needs less care and attention than any other part of the car, and it is safe to examine and go through every other part of the machinery before attempting to tamper with the magneto.
The Carbureter.—In the past carbureters have had a bad reputation, probably, deservedly so. The great difficulty with most of them has been in the floats, and the float connections with the inlets. This, and the fact that small particles, which somehow get into the oil, and block the flow at the needle point, and the presence of water, are the serious troubles.
One can be remedied only by a thorough overhauling, and the other by using special care in filling the tank with fuel. The float chamber should be kept clean, as well as the ducts and valve controlling the flow.
Sometimes a small fiber will be lodged somewhere in the pipes, and this will catch small particles, and temporarily arrest them. The accumulated mass when dislodged blocks the valve, and the mystery seems inexplainable.
Wrong adjustment in a carbureter manifests itself in three ways: If the smoke is black, and the flame is red, the mixture is too rich; a yellow flame indicates a lean mixture; and a blue flame and clear exhaust shows that it is properly set.
If an explosion takes place in the muffler, it is an indication that gasoline, or the vapor, has been carried over; and white smoke discharging from it shows that there is too much lubricating material going into the cylinders.
Weather will affect mixtures, and more air is generally required on a hot day than during damp weather. This explains why a machine will run without trouble with a certain adjustment one day, and be very unsatisfactory the next. These things should be observed and mentally noted.