INTRODUCTION: THE ENGINE MONITOR is a self powered LCD Hour meter, Tachometer and Maintenance Meter. .An internal lithium battery furnishes the power for the monitor. .A wire around the spark plug wire of the engine provides both a tachometer signal an indicator that the engine is running. The maintenance meter is used to alert maintenance personnel that a time interval has expired and maintenance should be performed on the engine. Before changing any settings to the ENGINE MONITOR, ensure that the engine is off.