Simple test for both condenser and coil

Ian in Mississauga

Senior Member
A few years ago I read about this test. Fiddle with the points to get a bright blue high voltage spark at least 1/4” long. Leave the the key on and the points closed or shorted. How long do I wait before checking the spark again? If the spark is the same then the coil and condenser are good.
TIA Ian
 
miliseconds - at 2500 rpm the coil and condenser are firing 5,000 times a minute on a 4 cylinder engine or 83 times a second.
 
Long enough to heat the coil/condenser. 5 minutes?
 

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I think it's important to test a condenser while it's warm. A condenser that tests good when cold might test bad when tested while it's warm. 120°F with a hair dryer should be warm enough.
 
First, I would jump across the points with a wire so there’s no risk to the contacts. Then you want to be checking the coil temperature, either with an IR gun or by touch. It should be quite hot, in the 120-140° zone. An oil-filled coil will get hotter faster, so if you have an epoxy coil I would stop at the lower end of that range.
 
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