I was working on one of my tractors that has a Kohler with the points & coil. I happened to think about my old Tach Dwell Meter sitting in the toolbox collecting dust & decided to try it on this. I set it to 4 cylinder & hook it up to the coil & ground. I took the meter reading & multiplied by 4 this seems to be very close to the right idle rpm for this motor. I did a Google search to find any information on doing this & everything I found started talking about dual spark & dividing, multiplying formula to get an accurate reading. My thought on this is What? / Why? These meters were designed for use on the point, rotor, distributer cap ignition used on automobiles years ago. Most of these are set up for 4 sparks per revolution for a 4 cylinder engine, 6 sparks for a 6 cylinder, & 8 sparks for an 8 cylinder. So my thought is if the meter is looking for 4 sparks per revolution & only seeing 1 spark that reading multiplied by 4 should be real close to the correct reading. Am I missing something here? To find a use for a meter that is collecting dust or for many to be trash is a good thing. Reading an analog meter accurately takes some practice but I learned to many years ago to discuss here to read these meters to MIL Specs. With the newer engines this will not work & also the engine needs to be points & coil for this to work. There are newer tachometers that are not that expensive & maybe more accurate but if you have one of these just laying around & are working on the older engines with this type of ignition why not use it. Again am I missing something on this thought. Memory & time often have many conflicts.