Low voltage at coil
Created by: whitewolf
Orig. Posting Date | User Name | Edit Date |
May 1, 2018 04:33PM | dklawson | |
May 1, 2018 03:42PM | whitewolf | |
May 1, 2018 03:41PM | whitewolf | |
May 1, 2018 12:25PM | dklawson | |
May 1, 2018 10:59AM | charrison | |
May 1, 2018 09:05AM | whitewolf | Edited: May 1, 2018 10:49AM |
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Do the tests, report the voltages and resistances you measure, and carefully examine the wires on the coil and tell us their colors and positions. From that we'll be able to tell you what is on the car and/or what you need.
Doug L.
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not sure where a ballast resistor would be or what it would look like. I will check the points test
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Sorry is volts, this worked last year but was getting hard to start when it put if up for winter.
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Colin is right, 6 Amps is too much current. Worst case with the engine off, ignition points closed, and key in the run position you should measure no more than about 4 Amps (give or take).
For explanation... voltage is the equivalent of "push", Amps is the equivalent of "flow". If you left all the wires connected and hooked up your multimeter, you were measuring voltage. To measure Amps you have to disconnect wires and put the meter in series where the wires were. (Don't go anal on me.... Yes, there are clamp-on ammeters and some even measure DC current but most people don't have those at home).
Assuming your car has points and not electronic ignition, try these tests and report your measurements.
1:
Remove the dizzy cap and put a penny between the points.
Connect your multimeter between coil (+) and an bare metal spot on the block or head.
Set the meter to measure volts and turn the ignition key to the run position.
What voltage do you measure?
(Don't forget to turn the key to the off position and remove the penny).
2:
Mark and remove the wires on the coil's low tension spade terminals.
Set your multimeter to measure resistance (Ohms).
Leave the ignition off (key out).
Measure the resistance across the coil's spade terminals.
What resistance did you measure?
(Put the wires back where they were on the coil's spade terminals).
For explanation... voltage is the equivalent of "push", Amps is the equivalent of "flow". If you left all the wires connected and hooked up your multimeter, you were measuring voltage. To measure Amps you have to disconnect wires and put the meter in series where the wires were. (Don't go anal on me.... Yes, there are clamp-on ammeters and some even measure DC current but most people don't have those at home).
Assuming your car has points and not electronic ignition, try these tests and report your measurements.
1:
Remove the dizzy cap and put a penny between the points.
Connect your multimeter between coil (+) and an bare metal spot on the block or head.
Set the meter to measure volts and turn the ignition key to the run position.
What voltage do you measure?
(Don't forget to turn the key to the off position and remove the penny).
2:
Mark and remove the wires on the coil's low tension spade terminals.
Set your multimeter to measure resistance (Ohms).
Leave the ignition off (key out).
Measure the resistance across the coil's spade terminals.
What resistance did you measure?
(Put the wires back where they were on the coil's spade terminals).
Doug L.
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Do you have a ballast resistor in the 12v feed to the coil ? If so it will reduce voltage at the coil.
Have you mixed up coils intended for a ballasted system with those for straight 12v.
How are you measuring the "low" voltage ? With the engine running, the coil voltage fluctuates as the points open and close, so will confuse many meters.
Do you mean amps or volts ? IMHO 6A is too high for coil current, and you will melt the points.
Have you mixed up coils intended for a ballasted system with those for straight 12v.
How are you measuring the "low" voltage ? With the engine running, the coil voltage fluctuates as the points open and close, so will confuse many meters.
Do you mean amps or volts ? IMHO 6A is too high for coil current, and you will melt the points.
Car engines make CO2 and trees absorb CO2. By running your engine you're feeding a tree and helping the environment.
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Im getting very low voltage at the coil so the mini will not start (1972) if i jump a hot wire to ignition it will start and then remove the hot wire (do not want to burn oil up) it will run, when running it voltage is about 6amps but before the hot wire it it voltage is 3amps. any ideas what has failed?