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Show ATJTO LESSON NO. 81. Carbureter Adjusting. The carbureter, the adjusting of which we will take up now, Is the Stromberg. There are quite a number of types of this carbureter on the market, but we will take up only the two which are the most used at present, namely, the type "G," found on the larger cars, and the type "K," found on the smaller cars. The Stromberg differs from most other1 i' carbureters. In that the adjustments are all on the air, instead of on the gas sprav nozzle. Tvpe "G" is a non-water jackMed model mod-el furnished in either single or double jet, arcordins to motor requirements. Whenever possible, install this carbureter carbu-reter with float chamber toward the radiator. radi-ator. ' GASOLINE ADJUSTMENT. The gasoline adjustment on this carbureter car-bureter is set at the' factory and never needs attention. 1 AIR ADJUSTMEXTS. There are only two simple adjustments that ever need attention, "A," the low-speed low-speed nut. and "B," the high-speed nut. With tho motor at rest, set the highspeed high-speed nut "B" so there is at least 1-16 of an inch clearance between the spring "G" and the nut "X"' above it. This is Imperative. Set the low-speed nut "A" so the air valve "K" is seated liehtlv. TO START THE MOTOR. Start the motor, first closing the choker valve 'R" In the air horn by the control con-trol provided. Open this as soon as motor mo-tor starts and keep open while motor is running. If motor does not start on the third or fourth turn of the crank open this valve and motor should then run. LOW SPEED. Do not adjust carbureter until motor Is thoroughly warmed up. When motor is warm and with spark retarded adjust nut "A" iip or down until motor runs smoothly at low speed. To determine proper adjustment open air valve with finger by depressing "X" slightly. If, when so doing, motor speeds up noticeably notice-ably It indicates too rich a mixture and "A" should be turned down notch by notch. If, on the other hand, motor dies suddenly when slightly opening the air vtwvts il iiiuu:H.i.ea loo lean a mixiuiR, aa,u "A" should be turned up until this is overcome. If mixture is too rich as indicated by a loading of the motor and heavv, black smoke from the exhaust turn "B" d"wn until motor operates properly. A further fur-ther test for the correct mixture at high speed can be made by depressing the air valve when the motor Is 'running at this speed. If when so doing motor speeds up It Indicates too rich a mixture, if motor mo-tor runs slower too lean a mixture. Turning either adjusting nut up means a richer mixture or more gas. Down means a leaner mixture or more air. To get the highest efficiency from this carbureter hot air equipment should be used. When this carbureter is furnished by the makers of the car, the nozzles will be right and you should not change them. If, however, some other make of carbureter carbu-reter was replaced by this one, the nozzles noz-zles may be wrnns, and the fallowing is given for this case. Changing the nozzles noz-zles on carbureters furnished by tlie car makers is a big mistake often made. DOUBLE JET TYPE. If, after following tlie instructions given above, and with the motor running idle at low speed, the air valve '"E" remains tightly seated, it indicates too small a primary nozzle "C" and a larger one should be substituted. If with the proper adlustment and after stopping the motor the air valve '" hangs off the seat, the nrimary nozzle is too large and a smaller one should be used. To ohanr-o primarv nozzle, remove pet cock or plug at "P." Insert screwdriver and unscrew nozzle. v If the mixture on low speed is correct, but In order to get the proper high sneel, adjustment is necessary to turn out "It" up so far that "G" is in" contact with "X" above it. after the motor is shut down, it indicates that the auxiliary nozz'e "J" is too smail and a larger one should be used. If it is necessary In order to ret the proper high speed ad hutment to t'-n nut "B" down so that there is more than one-eighth of an inch clearance hcJwecn "G" and "X" whMi motor is fO'.'it down, it Indicates ton large an aiivii'avy niile "J." and a smaller one shmiM be u-ed To chance auxiliary i-.o?z!c ".I" move air horn to one side, remove piug " r," insert screwdriver and unscrew "J." Nozzles are numbered n'Tording to drill cause sizes, for instance, Xo. r0 is lar-or than No. r.r1. SIXGLE JET TYPE. If after a'msting acrding to tNp above instructions, and with the motor shut down, the air valve "K'' bancs t-f t the seat, tlie primary nozzle "C is too large, and a smaller one should be used. If we get the motor to operate properly prop-erly it is necessary to turn "U" up so far that tlie high speed spring "C" Is in contact con-tact with the nut "X" the primary nozzle is too small, and a larger one .should be used. To change nozzles, see instructions above. The type K and K.O has no high-speed adjustment. The nut "A" is the only adjustment on this carbureter. The steam of this nut supports the lower end of a spring which controls the air valve. This air valve opt us downward Into the air chamber. T timing nut "A" clockwise or down tightens this spring and admits less air, thus producing a richer mixture! .Turning '"A" in the opposite direction 0TB.ntl-clockwise, 0TB.ntl-clockwise, produces a leaner mixture. TO ADJUST. Before starting the motor, turn nut "A" ant i-clockwise until a point is reached where, when lifting or pulling up on "A" a decided click is heard. (This is the air valve coming In contact with the seat.) Then turn "A" clockwise or down notch by notch until click Is no longer obtained when lifting the nut "A" as directed above, then turn two more notches in same direction. Tlie air valve is now on Its seat, which I is the normal position when motor is at ! rest. START THE MOTOR. To start the motor, raise tlie steering! prst or dash contmi to its highest posi- 1 lion. C,r;uU:ally lower control -,a the mo- j tor warms up and be sure same is In its , lowest position and that motor- is Ukt-ouuhly Ukt-ouuhly warm bei'ore adjusting the carbureter. carbu-reter. AP.TT'ST FOR TDI.E. ' AftT tlie moior is warm, turn "A" np or d'twn notch by notch until -motor idles proper'y. It should not be necessarv to turn tins more than a few notches either way if carbureter is set as above di-rci-ted. To rut "A" the only ad.iustmrnt and oo:itro;s the mixture on low and through; in'rmrdiate speeds. Rareiv will t'-.e noz- ! .,- r.r-i to b,- i ::an-.'d to et satisfactory j !o'.v-s:-''d adjustment. j X'4e the expression "i;p or down not-h ' hy notch" in the next lo the last para-i gr.'inh. 1'v this is meant that you should ! a turn of a nor--h. then take the i -;!-., d away an.! wait for half a minute or so t' SO'1 what the result Is. The effect ' of the turn will rot show instanttV' and ynu must wait lu-tween f-ach turn of the ' screw. Tliis apples to the adjustment of I all carbureters. 1 |