Are OMC Engines Special?
In the past I have read articles which mention that OMC engines require special tachometers, or comments to the effect that an after-market tachometer (a so-called univerasal tachometer) will not work as well with an OMC motor as an OMC branded tachometer. Is there any truth to this, and by that I mean is there anything unusual about the tachometer signal developed in an OMC which would make its electrical characteristics different from other outboard motors? I do acknowledge that there is always a tendency to recommend the OEM accessory in preference to an after-market accessory. This criterion is not important in this discussion. I also am aware that so-called universal tachometers have calibration settings which allow them to work with a variety of different pulse ratios. And again, this is not important. I am more interested in learning of any electrical differences, such as a difference in the voltage in the tachometer pulses, which might support the notion that an OEM instrument
