New Britain herald., 1929-09-03
AUTO INSTRUMENTS
 VERY IMPORTANT
Too Many Drivers Ignore Gua8eS
 on Dash

One of the most important duties connected with good automobile driving is that of reading the instru- ments on the dash. These instru- ments are there for an express pur- pose, yet few drivers cast an eye up- on them for the information that the can obtain from them, The req son is few know or appreciate the value of the instruments before them.
 Even the speedometer which is best known of all, is sometimes pis- read and misunderstood. Take the matter of speed alone. When the specdomcter shows the driver step ping on it an registers around GO or 70 miles an hour, the usual driv- CT will beast about the mileage shown on the dial as though he had actually made it.
 But this, in practically every case, is not so. The speedometcr happens to be the most unreliable instrument on the dash. It is calibrated, or set, on the average automobile to regis ter accurately when the car is going around 30 or g. miles an hour. At this speed it may be believed.
 But the speedomcter is so made that it cannot go up or down in eX- acty the same proportion as the ac- tual speed of the car rises or falls. Therefore, when the dial reads 60 miles an hour, the car may be going only about 56 or 57. When it reads 70, the car speed may be only 65, and 50 on. Below 30 or B, the ac- tual speed is slightly higher that that shown on the dial,
 The speedometer, also should be watched carefully for mileages at which the oil should be changed Many drivers gauge this duty by time rather mileage. Mileage how ever is the proper rule to follow. At every 1000 miles or so, the oil should be checked for proper viscOsity and should be changed if it is too thin, At the same mileage, the car should | be greased thoroughly.
 At the 10000 mile points, the oil filter. gas filter and air cleaner 1 might need cleaning or replacing. They should be checked by a com potent mechanic. Then again at ev- cry 10000 miles, the spark plugs might be ready for replacement, the valves ground and the cylinders scrapcd for carbon.
 By watching the speedometer while driving, and feeling the accel- 1 orator, the experienced driver can i tell whether he is getting the best cut of his fuel. His foot in it's va | rious positions toward the floor | board, is a telltale in cooperation with the Speedometer as to the ef- ficiency of the running parts of the car.
 If the speedometcr shows a speed | lower than what the driver expects from the car, bu the position of his | foot on the accelerator pedal, he can suspect such failures as that of a dragging brake, a slipping clutch or the emergency brake handle not full ly released. In the engine itself there might be a power leak some where, through the valves, the plugs or through loose piStOnS. Much of | the fuel that he might be feeding into the motor may lose itself un- burned down the cylinders into the
 oil pan, and the speedometer, in
 conjunction with the right foot, can tell.
 | In the matter of economy of oper-
 ation, the use of the fuel can only l be judged in the light of the speed
 at which the car has been run. Here the speedometer comes forth again as an important instrument. 1 Usually the most economical speed l has been found to be around 30
 miles an hour. Most engines have l been built for that because most of
 our driving is done at that speed.
 If someone tells you that he got
 good mileage on his latest cross
 country trip, you will discover on question him about his speed that he
 been loping along at the modest rate
 of 30 or 35 miles. If he complains
 that his gallons were consumed
 faster than he could record them,
 he most likely had been scooting