Re: Just replaced points need help
Over-simplifying here quite a bit for clarity . . .
Some engines, but not all, have both a minimum advance stop and a max advance stop. Your 9.5 only has the min stop and is implemented by the throttle stop adjuster on the tiller handle. Other engines have the stops directly under the timing plate, or on the throttle linkage at the motor. In a mechanical breaker-type ignition, spark happens only when the points break. Rotating the timing plate via the throttle changes when this happens relative to TDC. The only thing you really have to get precise is the gap. The throttle handle will make the timing advance change manually as you rotate it. This all relates to the _ignition_ advance.
Note: the "throttle" only directly manipulates the timing relative to TDC which is why it's really an advance control and not a throttle. More on this in the following:
Now, the butterflies on the carb are mechanically coupled to the ignition advancement mechanisms, but there is no means for you to directly manipulate them. They are secondarily controlled via the throttle advance cam.
In this system, the timing is always dead-on exact. After all, you manually put it where you want it to be. It's the carb butterflies that may be out of sync with the timing advance.
What about those points?
The gap of the points controls two things.
1) The relationship between where the cam-follower is on the cam and the point at where the coils discharge.
2) The amount of time the coils continue to charge up after discharging via the spark plugs but before closing (the difference between the opening and the closing).
The critical thing for your outboard is #2. After the coils charge up and fire they continue to build up current in the windings which really really wants to discharge via the point gap. They need to close before this gets great enough to jump the gap and toast the points. The condensers help, but can only service the demand for so long.
