A timing light uses a strobe flash to determine the ignition timing of a car, which is the frequency of spark plugs firing. The timing light illuminates marks that the car manufacturer has placed on the engine's crankshaft pulley or flywheel. The position of the marks when the engine is running indicates the timing of the spark in relation to piston position. The Equus Xenon, also called the Innova, uses a xenon bulb to read settings and connects to the spark plug with an inductive pickup. While timing analysis can be performed at home, a repair manual for the vehicle make and model is necessary to determine if the timing is set correctly.
Locate the timing mark and reference pointer, which are typically located on the crankshaft pulley, vibration damper or on the flywheel. Make sure the timing mark and pointer are clean and visible, using chalk to define the marks if necessary.
Connect the timing light battery clips to the vehicle battery, placing the red clip on the positive (+) battery terminal and the black clip on the negative terminal. Attach one end of the supplied inductive pickup leads to the bottom of the timing light handle and the other part to the number one spark plug cable.
Start the engine and run it until normal operating temperature is reached. Turn on the timing light by pressing the "On/Off" switch, and the timing light will begin flashing. Adjust the timing light barrel to direct the light toward the timing marks.
Note the position of the rotating timing mark in relation to the reference pointer. If the readings are within the range advised in the vehicle's repair manual, the ignition timing is correct. If the timing reading is not in range, an adjustment or part replacement may be necessary
Press the "On/"Off switch to turn the light off after use, then turn the car engine off and remove the battery clips.
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