Timing Lights
by Thomas Dermody

Time. It flies, it marches on, it waits for no man. And when it's up... BUT, as it marches on and leaves our old trucks behind, the modern tools we take for granted also leave us behind. Or do they? Here's Thomas Dermody to answer a dilemma of this modern age -- Can we still ...

Time a 6-volt vehicle with a modern timing light?

         Regarding timing a 6-volt car with a 12-volt timing light, most modern timing lights that connect to the battery do not use an incandescent bulb.  I don't know of a timing light that uses an incandescent bulb.  The reaction of the filament wouldn't be quick enough for the purpose.  Traditionally, the timing light that hooks directly to the spark wire uses a neon bulb. 

         The new lights that hook to your battery, with an induction sensor clipped over the #1 wire, use a xenon bulb (flashes white, like the flash in a new camera).  There is no way to change this bulb, and furthermore, the bulb doesn't operate at 6 or 12 volts anyway.  There's a device inside that raises the voltage to 1000 volts or more.  They do make timing lights that will work on both 6 and 12 volts.  They have a switch inside.  However, I have found that many cheap "12-volt only" timing lights will work just fine on 6 volts.

         The particular light I use works well as long as the battery is charged (supply will then be at approximately 7 volts).  If the battery is drained, allow the engine to charge it, and then reduce idle.   

         The neon type of timing light will, of course, work on any car, since it is connected directly to the spark plug, and receives its voltage from the spark plug (several thousand volts--the same in both 6 and 12 volt cars).

Bottom Line -- Most 12-volt timing lights will work on 6-volt systems!  

Thomas Dermody
Bolter # 12958
Milwaukee, Wisconsin

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v. February 2007