[Healeys] *** SPAM ***Re: Timing light query (OOPS)

sentenac.rw at gmail.com sentenac.rw at gmail.com
Mon Mar 11 23:13:26 MDT 2019

The problems I was mentioning only happen if you use the car's
batteries for a supply to the light.  If you use an independent
battery and don't somehow link one side of the supply battery to the
car's chassis you shouldn't have a problem.

On Mon, 11 Mar 2019 22:07:19 -0700, you wrote:

>Polarity also matters in a different way if your timing light has a
>metal case  and one of the power leads is grounded to the case, as
>mine is.  If you use a 'regular' timing light designed for negative
>grounds in a Healey with a positive ground system, and if you then
>touch the case to the chassis or engine you will get a lot of sparks
>at a minimum, and maybe do some welding where you had not intended to.
>BN1 #724
>On Mon, 11 Mar 2019 21:32:53 -0400, Michael Oritt wrote:
>>The 12VDC lead does not need to go to the battery, merely a source of power
>>whether or not it is part of your car's electrical system.  I don't know
>>how your engine is configured but you can take power off of the starter
>>solenoid, coil hot lead, etc. etc.  Polarity does matter, however.
>>Best--Michael Oritt

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