STANDARD AUTO-ELECTRICIAN'S MANUAL SECTION A A 26 which makes it possible for the cor of ignition coil to become fully magnetized and thoroughly saturated before the next break tak s plac . Why These Distributors Must Be Synchronized: In the case of the old type distributor the interval between breaks was determined by the position of the lobes on the cam. With an eight lobe cam a break was bound to occur every 45 degrees of. distributor shaft travel, corresponding to 90 degrees of flywheel travel. With the high speed distributors, however, which make use of two sets of breaker points, each s t taking car of four cylinders, the breaker arms must be accurately located that the primary interruptions will occur at exactly the correct intervals, or 45 degrees apart. To meet this requirement one set of breaker points is mounted on a movable plate, and an eccentric adjusting screw is provided for changing their position. HOW TO SYNCHRONIZE POINTS Distributor on Engine: 1. Remove distributor cap andjjUpr button. 2. Adjust both sets of contact poflHpiG^O to .024 inch. (For accuracy use a thickness gauge). The fixed breaker points are adjustable for gap opening by loos ning LOCK SCREW " A " (Fig. 6 ) , and PIVOT SCREW " B " , and adjusting with ECCENTRIC SCREW " C " . After making correct adjustment lock both SCREWS " A " and " B " . The movable breaker points are adjustable in the conventional manger by us of point wrenches. 3. Connect a 6 volt test light, one side to either of the insulated arms, and the oth r side to ground. 4. Turn "on" ignition switch. (With test light connected in this manner the light will burn when points open, and go out when closed). 5. Insulate the movable set of points by inserting a piece of fibre between points. 6. Hand crank engine slowly until fixed breaker points are almost ready to open. (This will be indicated by test bulb lighting when breaker cam back lash is turned in the direction of rotation, and bulb going out when the back lash is turned against rotation.) FIG. 6. 7. Replace rotor button on cam. (On top of the fan tail of rotor will be found two Adjusting Screws on Auto-Lite, Type IGH synchronizing marks ( " A " and " B " , Fig. 7) accurately spaced at an angle of 45 degrees.) Distributors. 8. With the rotor back lash taken up in the direction of drive, place synchronizing gauge (see Fig. 0) on edge of distributor base, so that its point is exactly in alignment with the clockwise line, (for R. II. rotating distributors) or the counter-clockwise line (for L. H. rotating distributors), when test bulb lights. (This is the exact position of break for. this set of points. The other set of points should open when engine is slowly cranked, and the trailing degree mark ftg^rotor is exactly opposite the synchronizing gauge point.) TP& FIG. 7. The synchronizing gauge shown in Fig. 8 will be found listed in the tool section of this Service. Auto-Lite "Special Master Timing Rotor" #10-157*. 9. Before this last test is made the fiber wedge must be removed from between the movable set of points, and placed between the stationary set. 10. If the test light shows the distributor to be out of adjustment loosen the two LOCKING SCREWS " D " (Fig. 6 ) , and adjust by moving sub plate with ECCENTRIC SCREW " E " until proper setting is obtained. Lock SCREWS " D " after completing adjustment. NOTE: The use of an eccentric adjusting screw has been discontinued and on late model units it is necessary to move the plate by prying it around with the point of a screw driver. 1 1. Repeat above operations several times to assure an accurate adjustment. It is to be remembered that the distributor shaft turns one-half flywheel speed, and that a discrepancy ef but 1 degree on the cam Jvill be twice as much on the flywheel. For smooth engine performance accurately synchronize the points. UH FIG. 8. Auto-Lite Distributor Synchronising Gauft #IGH-1. TO SYNCHRONIZE POINTS IN TEST BENCH The ideal place to synchronize all high speed distributors is in a test bench which has a rotary spark gap, laid off in degrees. Synchronizing by use of a test bench, not only is much easier, but very much more accurate, and at the same tim th number of degrees the primary circuit remains interrupted can also be checked. This is a factor overlooked when synchronizing tools are employed, and an item our engineers have found to be very important if the best results are to be obtained at high speeds. This interval is varied by slightly changing the breaker contact separation. Test Bench Method:—(Test Bench Drive Motor is not used). 1. Place distributor in vise. 2. Connect either the panel voltmeter or the six volt test light in series with breaker points. 3. Turn distributor base in vise until stationary set of points open wh n point r is at z ro on rotary gap. (In clamping distributor shaft and base mak sure all back lash is eliminated.) 4. Slowly turn shaft (by hand), watching the voltmeter or light to se when primary circuit is again completed. (Note number of d grees, which should be approximat ly 12°.) 5. C ntinue to turn shaft until second set of breaker points op n. This should occur at exactly 45 degrees after the first break. Copyright 1929, by Standard Engineering and Publishing Co.