Review on 📊 Compact Tachometer Hour Meter Gauge for Oil Change Monitoring on Boats, Lawn Mowers, Motorcycles, Outboards, Snowmobiles, and Chainsaws by Andy Metzger

I used a digital tach on a Snow King Tecumseh 4-stroke engine that needed a top RPM adjustment after an overhaul. I was able to get the engine close to revving "by ear" but I needed this tachometer to set the RPM to match the engine spec. I put the battery in and turned on the tachometer. My engine has a magneto that fires once for every revolution of the crankshaft, similar to a 2-stroke engine, so I went with the 1P1R ignition scheme (see instructions for 3 ignition options). Then I wrapped the speedometer wire around the spark plug wire three times and started the engine. It immediately showed an RPM that was 300 RPM below engine spec. The RPM readout was very stable and tracked fairly quickly as I moved the throttle from idle to full RPM. The display refresh rate is set to every half second. I set the engine governor RPM to spec and shut the engine down. I then pressed the M and S keys simultaneously to turn off the speedometer. I can't confirm the accuracy of the tachometer as I didn't have another tachometer to compare to, but it was very close to my original 'by ear' RPM setting. I didn't use the hour meter functions.