Bisbee daily review., 1921-05-08
OF
 CARbURET0R |S
 DELICATE TASK
BY FRANK THAYER of Thayer's Garage, Lowell

The carbureter must function prop erly to have your car run smoothly and pleasantly, on the minimum amount of gas. The first and most important thing in the engine cycle is to get the fuel into the cylinders; principal part of which is the carbur- eter.
 This is far from being a simple proposition considering the vast num- Der of different makes of carbureters on the market. and many car owners make the mistake of thinking it sim pie thing to adjust a carbureter, and attempt themselves, thereby making it worse and eventually having to have an experienced man adjust it, after having fouled engine with carbon dur ing their experiments. There are cer- tain proportions of gas and air mixed that go to make up a perfect combus- tible mixture, but garages or mech anics have no means of measuring or testing to produce these correct pro- portions, and they have to depend en- tirely upon their sense of hearing, and the functioning of the engine. In or der to obtain a perfect adjustment the mechanic must know by the sound and action of engine what to give it in the way of more or less gas or air, to get maximum power, gasoline consump- ton, and the pleasant sensation of a smooth running engine.
 It is an authoritative fact that any gas engine loses one horsepower per thousand feet altitude, and that the atmospheric pressure is of vital i'm portance in the proper adjustment of carbureter. Viz: the sea-level at mospheric pressure is 14.7 pounds per square inch, and Bisbee being 5000 it. in altitude. has an atmospheric press ure around 12 lbs per square inch; so it stands to reason that owing to the difference in the density of the atmos- phere at different attitudes, sea-level carbureter adjustment would not be satisfactory in this altitude, and it can be plainly seen that carbureters ad- justed here require more air than those of lower altitude.
 Automobile Engineering" treats on this subject in the following:
 Probably no one detail in the whole list of carburetor parts has caused, and still does cause. more difference of opinion than the source of and ad- justment of the air supply. and its companion, the adjustment of the gas oline spray. The latter drew atten- tion long before the former; in fact, the former is more of a modern ap- pliance. The fuel spray was investi- gated long ago; for the gasoline spray had no adjustment. the size and the location of the level of the nozzle were fixed. The spray itself, however, re- ceived special treatment. It was pro- jected against a conical spray deflec- tor which served to break up the col umn into finer and more diffused par ticles. In this way, great vaporizing action was gained. Practically all the moro modern vaporizers use an auxil- iary air valve, sthis is a partial nee essity with the heavier fuels. That is. it has been found that the heavier fuels require more air to vaporize them than can be supplied by the pri- mary air inlet Moreover, these heavy fuels require considerable additional heat in order to vaporize and the aux Hilary inlet has been made the vehicle for conveying this. This is generally connected with the exhaust manifold in such a way that the air entering through it is heated to a high tenn perature Adding this after the fuel has been split up by the spraying noz- zle and the primary air has proved very successful" From here on this article goes into intricate details and illustrations, so it would be impossible to present more of it in this article, but this will doubtless impress you with the importance of q proper car buretor adjustment, and the inability of an amateur to obtain this adjust ment