@Dave_C posted:My problem engine was the way the tach reader mounted to the motor.Ran fine most of the time. For some reason the gap didn’t stay consistent. Just adding the slightest downward pressure kept the chuff consistent. This was accomplished with a roller base. A simple brace seemed to work to steady it and fixed the problem.
Mounting the tach reader properly would have fixed this properly and you'd never see the problem again.