Ignition coil test

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Dusten

Dusten

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I tested my Accel Super stock coil 8140C. Primary coil was 1.3ohm and Secondary coil was 6,800ohm. The spec sheet said primary should be 1.4ohm and secondary coil should be 9,200hm. I could not find online what range is acceptable. The secondary coil 6,800ohm seems very low to me but I am not sure that means my coil is bad and needs to be replaced or not. Thanks in advance for any help.
 
did you test it at the rated operation temp, all those reading will change!
 
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.............And what did you test it WITH? Incorrect answer is "my 3 dollar Harbor Freight............."
 
67Dart273 said:
.............And what did you test it WITH? Incorrect answer is "my 3 dollar Harbor Freight............."
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Funny that you say that, it was a multi meter from Harbor Freight and it was like 5$. I was thinking it was junk because when it is on 20 ohm setting I test the same thing and get a different reading every time. Do you think it could just be the meter is not reliable? What is a good multi meter brand to get?
 
Dusten said:
Funny that you say that, it was a multi meter from Harbor Freight and it was like 5$. I was thinking it was junk because when it is on 20 ohm setting I test the same thing and get a different reading every time. Do you think it could just be the meter is not reliable? What is a good multi meter brand to get?
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Hello Dusten,
Regarding meters when in dought if a meter is correct / incorrect you can use a known value like a resistor.
By testing the meter with several resistors of different values you can get an idea if the meter is reading correctly throughout a wide range.
If the meter is off compared to the known value you can just figure that offset into your equation.
You can buy a kit like this if needed.
https://www.amazon.com/dp/B07GDLDF1X/?tag=joeychgo-20
Did you reach out to Accel for info?
Ignition Technical Support - Holley Performance
A quality meter is always best.
Here we have Fluke and tektronix meters and scope's.
Hope this helps
Happy Mopar :)
Arron
 
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Dusten said:
No spark at all. Was testing the coil to see if that was the reason why.
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Ohm test is not a good way to test. The secondary has hundreds of turns of enameled wire, one short, turn to turn, ruins a coil. Ohm meter finding a single shorted turn would be impossible. In your case finding significant difference, might be problem, perhaps short between layers, but no way to be certain.
Here is the typical test. First insure there is voltage at coil (+) with ignition on. Turn off ignition. Place plug on coil to cap cable, connect plug case to engine ground. This bypasses rotor. Place voltmeter between coil(-) terminal and ground, with helper, view meter while cranking engine a revolution or two. The meter reading should bounce and plug may fire. If meter reading does not change, problem is in points, wiring ... If that happens, remove any wires connected to coil (-) then use a insulated clip lead to momentarily ground it, with ignition on. It only takes about 0.003 seconds to charge coil, when opening connection, spark should happen for good coil. Shock hazzard exists if touching coil (-).
 
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