Apr. 1. 1912 



My ad\ice to prospective buyers is to use 

 the same judgment in buying a machine as 

 in buying a horse. The one that costs the 

 least is not always the cheapest in the long 

 run; and if the machine is being sold with 

 a oji-inch tire, have a four-inch put on in- 

 stead. It will be money well spent. 



Hanford, Cal. 



USEFUL HINTS FOR THE PROSPECTIVE PUR- 

 CHASER OF AN AUTOMOBILE. 



BY CYRIL BRODNIX. 



From my ten years' experience with gaso- 

 line engines and automobiles of some 

 twenty-Hve or thirty ditTerent makes, I find 

 that one of the most misunderstood points 

 is the ([uestion of horse-power. The Society 

 of Automobile Engineers' (S. A. E.) rule 

 for obtaining horse-power is to multiply the 

 square of the diameter of the cylinder by 

 the number of cylinders, and divide by 2.5. 

 The number of revolutions per minute, and 

 the length of stroke of the piston, are not 

 counted, although each has something to do 

 with the actual horse-power that the engine 

 is cajiable of developing. This rule, there- 

 fore, is only approximate. 



An engine that will develop 15 to 20 horse- 

 power is usually suflicient for a machine 

 seating two or three people; and one that 

 will develop 20 to ;V2 horse-power for one seat- 

 ing four or five people. A larger engine 

 costs more to operate, and nothing is gained; 

 for twenty-five to thirty miles per hour is 

 as fast as it is safe to drive on country roads, 

 and this speed may be easily maintained 

 with the sixes of engines given. 



The single-cylinder machine is the sim- 

 plest, most economical, and the lowest in 

 first cost; but single-cylinder motors are 

 limited to 10 or 12 horse-power on account of 

 the (lifTiculty of cooling the piston if a larger 

 cylinder is employed. The two cylinder 

 engine has some advantages over the single 

 cylinder; but the four-cylinder engine is 

 usually considered to give the best service 

 on account of its more uniform power and 

 com|)arative lack of vibration. The six- 

 cylinder engine gives still steadier power, 

 and has almost no vibration; but it is more 

 complicated, more expen>-ive, and much 

 heavier than a four-cylinder engine of equal 

 power, and for this reason it is very seldom 

 used on cars selling at a medium ])rice 

 The water-cooled four-cylinder engine, there- 

 fore, of the four-cycle type, located under 

 the hood, gives the best service in medium- 

 sized cars. 



The engine should be so placed in the 

 frame as to be easily reached for cleaning, 

 adjusting, and repairing. It is a good thing 

 if the crank case hashandhole plates on the 

 side to ])ermit arljusting the crank pin or 

 main bearings without having to remove 

 the under half of the case. 



The valves in the cylinder head should be 

 of ample size, and located .so as to permit 



211 



easy cleaning and grinding. The valve 

 stems should have ample guides to keep 

 them in line, and should be protected by 

 some kind of housing or cover plate to keep 

 out the dust and dirt, and also to muffle 

 the noise. 



If a water-pump is used it should be lo- 

 cated so that the packing may be easily re- 

 newed. 



The magneto should be in such a position 

 that the contact point and connection may 

 be easily inspected and tightened. 



The carbureter should be set high enough 

 in relation to the frame so that the gasoline 

 feed-pipe may be readily disconnected for 

 cleaning. 



The oiling system should be capable of 

 delivering plenty of oil to all moving parts 

 all the time. Such parts as the pistons, 

 wrist pins, crank i)ins, crank shaft, the half- 

 time gears, cam shaft, cam-push rod, and 

 valve stems should be automatically oiled. 

 There should be rollers on the cam end of 

 the \^alve-push rods. 



The three-speed forward and reverse selec- 

 tive sliding-gear transmission is the one 

 most used, and the one to be preferred on 

 account of its positive action, long life, and 

 freedom from trouble. 



The clutch that gives the least trouble is 

 the one that is the simplest and that has 

 the fewest parts. The cone clutch having 

 an asbestos fiber face is usually to be recom- 

 mended on this account. A leather face is 

 all right, although it is more likely to burn 

 if the clutch slips. 



The universal joints of the shaft drive 

 should be so made that they run in oil, 

 thereby reducing their tendency to cut. 



The rear axle to be recommended is of the 

 full floating type; that is, one in w^hich the 

 weight of the car does not come on the 

 shafts that drive the wheels. The best rear 

 axles are equipped with Timkem roller 

 bearings throughout. 



There should be two sets of brakes acting 

 independently of each other, acting on the 

 drum attached to the rear wheels. The one 

 set should be internal, expanding metal to 

 metal, and the other external contracting, 

 the band having an asbestos lining. The 

 external brake should be used for service, 

 and the internal for emergency. The ob- 

 jection to a brake on the driving shaft is 

 that it sets up undue strain and jars on the 

 differential and the rear-axle assembly in 

 general. 



Before buying a car it would be well to 

 ask the dealer the following questions: 



How many miles per gallon of gasoline 

 and oil will the car travel? 



Are the valve stems and springs of the 

 motor i)rotected from dust? 



Is the water-pump easily repacked? 



Are the magneto and carbureter access- 

 ible ? 



Will the clutch act somothly without 

 sticking or slipping? 



Is the transmission case accessible ? 



Is the rear axle strong enough? 



Thorp, Washington. 



