The compression is maintained when the piston rings and grooves are free from gummed oil or carbon and move freely; when the cylinder walls are not worn oval by a slapping piston, or creased by carbon, and when a film of lubricating oil is constant on the side walls and when valves are properly seated. Loss of compression means loss of power and the cylinders should be tested every little while to make sure that no cylinder is failing to do its duty. More will be said concerning this later, as well as of minor things which may affect the compression.
As has been mentioned, to keep the engine running for any length of time there must be a cooling system, a system of lubrication, and a free exhaust. Once the owner comprehends the simplicity of gas-engine operation, he can begin to trace each part of the operation, learning all there is to know concerning the several steps in his own motor, and absorbing the specific knowledge which will enable him to care for his car efficiently and economically.
CHAPTER V
EQUIPMENT AND ACCESSORIES
With every car are furnished all the things required for operation, including lamps, tire pump, jack, tire-repair kit, a variety of wrenches to fit all nuts and bolts, oil can, set of spark plugs and generally an extra one; hammer, screw driver, cold chisel, magneto-adjusting wrench, and some other things, varying with the car.
There are any number of additions which may be made in the way of tools, or of devices which some motorists deem desirable. Some of these things are a speedometer, a clock, trouble lamp attachable to a socket on the dash, a mirror to enable the driver to see what is going on back of him (compulsory in New Jersey and some other States), cigar lighters, foot warmers, and elaborate lights for the limousine. The owner is cautioned, however, against loading up his battery with a lot of electrical devices which use up current very fast. Not so as to tools; one may err in having too few rather than too many.
While it is true that a woman with a hairpin and a piece of string can fix almost anything under the sun, the autoist would better not trust to his wife’s ingenuity, but be a little better prepared for the emergencies of the road. It does not do any good to know what the matter is when the car balks unless one has the tools and material to do the necessary repair work or adjustment.
Every new car is equipped with certain tools, but some owners have no interest in these tools and lose most of them in a short time, so that when needed they are missing, while other owners add sufficient tools to equip a good-sized machine shop.
A wise selection of tools for the car will provide everything at all likely to be needed on tour, and yet capable of being packed in such a compact space that it does not become an annoyance through the room occupied, nor weigh down the car. The special tools furnished should be preserved with great care, because nothing else fills the bill quite so well. To these might be added some few tools and parts not needed often, but when they are, their absence is a source of delay and is temper-provoking.
Recently the author was asked to go about fifty miles into the country to bring in a machine which had refused to run and had been stored in a barn over night. He found that the interrupter points had become glazed so that no spark was being procured. A special file is manufactured for the particular purpose of cleaning off these points. As one of these was not in the car, it was necessary to disassemble the spark timer completely, take out the points, and then find a piece of flat hard stone upon which the points could be cleaned. This did the work all right, but much time could have been saved if the interrupter point file had been carried in the car.
Likewise no wrench was available for adjusting the points and it was necessary to go to a nearby blacksmith shop and saw out a temporary wrench for the purpose. Word has come from France to the National War Work Council of the Y. M. C. A. that one of their supply cars serving the huts in the trenches was laid up nine days for the lack of a small magneto wrench.