How to check a coil
Muffin1
Posted 2018-11-06 3:26 PM (#573063)
Subject: How to check a coil


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Is there a way to check a coil on the engine to see if it is good. Or
do you have to take it out and go to a repair garage and have it checked there ?
Thanks Alex
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wizard
Posted 2018-11-06 3:49 PM (#573064 - in reply to #573063)
Subject: Re: How to check a coil



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Yes, check the prinary side between + and - on the coil; with the wires disconnected with an ohm meter. You should have roundabout 1.5 ohms. Check the secondary side between + and distributor connection, the value should be roundaboth 9 ohms in an oem coil.
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LostDeere59
Posted 2018-11-06 5:18 PM (#573067 - in reply to #573063)
Subject: RE: How to check a coil



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Location: Hilltown, PA

Also do a dynamic test if it works but you suspect poor output. Simply pull the secondary or ignition wire loose from the center of the coil and hold it a short distance away form the coil terminal. A good coil will produce a spark that is bright blue to white in color, and will consistently jump a gap of 3/8 to 1/2 inch. A poor or weak coil will generally only be able to muster a yellow spark that barely manages a 1/4 inch gap.

Of course proper dwell affects this, as does the capacitor and condition of the points. Point style ignitions may only see a yellowish spark, but it should be bright and able to jump a large gap.

Electronic conversions should be more in the blue to white range with larger gaps.


Gregg
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Muffin1
Posted 2018-11-06 6:53 PM (#573073 - in reply to #573063)
Subject: Re: How to check a coil


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Thank you gentleman
Alex
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