"Morgans" wrote in message
...

How does the notch help in telling the rotational position?
--
Jim in NC


Without giving too much away...
The notch depth is more significant than any vibration. If using a
proximity measurment, it is easy to determine when the notch occurs.
The notch is aligned with a known position (engineer inserts notch when
pistons/crank is in known position). This gives a phase reference. You can
compare where in the cycle a disturbance (knock, rub, etc) occurs with
relation to the notch. On recip applications, often a multi-tooth wheel is
used in addition to a phase reference for more accuracy.

Adam
N7966L
Beech Super III