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LETS TALK ABOUT TIMING

BASICS

  • 1. If the ignition has points; it fires when the points open. This is true for both battery operated and magneto ignitions.
  • 2. A buzzer is a simple device that indicates just when the points open.
  • 3. Advance is thought of in two different ways; the ignition and the crankshaft. Racers deal in real time or crankshaft degrees, while engineers and servicemen deal in half time or ignition degrees as the ignition is one half engine speed. Racers also deal in total degrees at the crank. If you have an ignition with automatic advance, you have some kind of system to advance or retard the ignition. If your ignition is "locked out", this means there is not an automatic system and the movement is "0" degrees.
  • 4. If you want to run 36 degrees and your ignition is locked out, you must set all advance on the crank pulley. If you wan to run 36 degrees and your system has automatic advance, that advance must be determined before you start. For ease, let's say your ignition has 20 degrees automatic and you want to run 36 degrees total - 36 degrees subtract 20 degrees equals 16 degrees. By simple addition and subtraction, you can see the crank must be set on 16 degrees B.T.D.C. If your crank is not degreed, it should be. You can buy a timing tape at most speed shops for different size balancers (or crank pulley). Some machine shops have the capability of turning and degreeing your balancer for a small charge. If you cannot find a tape or a machine shop, then you might do it yourself. Find where TDC is and mark it exactly on the pulley. Next, with a good tape ruler, measure the balancer or hub circumference and divide by 360, then multiply the answer by 10, 20, 30, 40 or what ever marks you wish to mark on the pulley. If you have a stock balancer, do not assume the "0" degree is at the right location. Many times these marks have turned on the hub and are no longer accurate.

TIMING

  • 1. Determine the total amount of degrees you wish to run in the engine.
  • 2. Determine the total amount of degrees your ignition
  • 3. Through additions & subtractions, find out where to set the crank BTDC, and do it now!
  • 4. Find out where the number 1 cylinder segment is in the cap and mark on the outside case of the ignition with a marker.
  • 5. Find out where last cylinder segment in the firing order is on the cap and mark that on the outside of the ignition case.
  • 6. Line up all intermediate oil pump drives and gear drive so as to place the rotor approximately � of the way between #1 cylinder segment and the last segment in the firing order when the ignition is firmly seated on the manifold or block surface.
  • 7. At this time you should check the play between the intermediate shaft and the ignition or the block and the thrust face on the gear. Some play or clearance must be present. If not when you tighten your ignition down, you might be jacking your oil pump gear through the bottom plate of your pump.
  • 8. Put the retaining clamp on now and just snug up the bolt / nut retainer so you can move the ignition with a slight amount of resistance.
  • 9. Hook up the buzzer to the primary wire and a good ground and turn it on. The buzzer may be buzzing now or it may not , don't worry at this time.
  • 10. Determine which way the rotor rotates and hold back against it with your thumb and apply a few ounces of pressure.
  • 11. Turn the outside case of the ignition against the rotation until the buzzer just stops. You might have to do this 2 - 3 times to get the feel of it, but the mag will fire just as the buzzer stops (this is when the points open).
  • 12. Tighten up the ignition retainer bolt / nut until the ignition will not turn.
  • 13. To check if your right there in the ball park ignition wise, reach up and grasp the rotor and turn it the way you did before. It should quit buzzing and now buzz with the alternate application and reduction of pressure on the rotor.

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