testing the coil
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Hopefully your voltmeter also has a resistance scale. If so, check teh primary winding resistance (from the primary terminal to the case ground or ground terminal). You should be able to meter between 0.5-1.5 ohms. Then sheck the secondary winding from the spark terminal to the ground terminal or case. That should yield about 6,000-10,000 ohms.
Those values are for a stock epoxy filled coil (square one), and aftermarket coils may have different resistances, but they should be similarly low and high. They key is that you have some continuity on the primary side and not below a few thousand ohms on the secondary.
Those values are for a stock epoxy filled coil (square one), and aftermarket coils may have different resistances, but they should be similarly low and high. They key is that you have some continuity on the primary side and not below a few thousand ohms on the secondary.
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my volometer has resistance but i still can't get a reading at all.
"check the primary winding resistance (from the primary terminal to the case ground or ground terminal). " is this plug that goes from the ignition modual to the coil? where exactly do i put the red side?
"Then check the secondary winding from the spark terminal to the ground terminal or case." is this the spark plug post?
i tried it with the power on and off.
"check the primary winding resistance (from the primary terminal to the case ground or ground terminal). " is this plug that goes from the ignition modual to the coil? where exactly do i put the red side?
"Then check the secondary winding from the spark terminal to the ground terminal or case." is this the spark plug post?
i tried it with the power on and off.
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Resistance tests are supposed to be done with all power off. The meter supplies the necessary current to test the resistance of the circuit.
For your tests, polarity really doesn't matter. In other words, the red and black leads don't have to be in any particular order since you are only reading plain resistance, no semiconductors.
To check your meter before testing, connect the two test leads to each other and you shoudl get a zero resistance display (0.00 ohms). If there is a problem with a lead or your meter, you will not get the zero display. If it's working, you're ready to test.
It sounds like you have the epoxy filled (rectangular) coil. If that's the case, there are two leads that use push-on terminals from the HEI module and one spark post. One of the two push-ons is a ground, or common lead. Measure between that and the other push-on to get the resistance of the primary winding (between 0.5-1.5 ohms). Measure between the common and the spark post to get the resistance of the secondary winding (around 6,000+ ohms). If either reading is way off the specs, the coil is suspect.
For your tests, polarity really doesn't matter. In other words, the red and black leads don't have to be in any particular order since you are only reading plain resistance, no semiconductors.
To check your meter before testing, connect the two test leads to each other and you shoudl get a zero resistance display (0.00 ohms). If there is a problem with a lead or your meter, you will not get the zero display. If it's working, you're ready to test.
It sounds like you have the epoxy filled (rectangular) coil. If that's the case, there are two leads that use push-on terminals from the HEI module and one spark post. One of the two push-ons is a ground, or common lead. Measure between that and the other push-on to get the resistance of the primary winding (between 0.5-1.5 ohms). Measure between the common and the spark post to get the resistance of the secondary winding (around 6,000+ ohms). If either reading is way off the specs, the coil is suspect.
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