Reply To: Thrust, hp, and weight comparisons

[Charles Myers]

Thank you for your help.  I am still tinkering with the motor settings.  Here is my latest attempt at making settings.

1. Motor in forward gear (not running of course).
2. At max throttle, the arm on the port side of the carb for the axle of the throttle butterfly is all the way against its stop. The butterfly is fully open.
3. The “mag arm” (as you labeled it in your second photo and where the spark plug wires attach) is not against its stop. I can, by hand, press against the port side of that arm to try to move it to its stop.  (Is it supposed to be movable by hand?)  It is springy, but does not move all the way to the stop. (Interestingly, the Evinrude parts diagram and list just calls the “mag arm” the “H.T. lead to armature plate anchor.”)
4. I then release the collar on the long throttle arm (that term is from the Evinrude parts diagram and list, although some are referring to that as an “economizer”). That causes the arm on the port side of the carb to spring back, and the throttle butterfly closes.
5. At this point I can push against the “mag arm,” and it moves all the way to its stop.
6. Holding the “mag arm” against its stop, I then press the long throttle arm forward to rotate the arm on the side of the carb and open the throttle butterfly fully. I tighten the throttle arm collar.
7. At this point everything seems OK. The butterfly is open; the arm on the side of the carb is at its stop; and the “mag arm” is at its stop.
8. As at test, I pull the throttle all the way back, and then advance it to full throttle. Something has changed, the “mag arm” no longer reaches its stop, and the collar has to be moved a little to restore a fully open throttle butterfly.

If it is critical for the “mag arm” to be all the way against its stop, what am I doing wrong?