jpwinger
Well-known member
What does ballast resistor do
That's exactly why...to give full batt voltage to the coil while cranking, then lower the voltage while running. On older systems with points, full batt voltage thru the points would burn them much quicker. Dropping the voltage allowed them to survive longer, but still work just fine. Some cars used a resistor wire instead of a resistor block, to do the same thing. Lowering the voltage on the coils keeps the heat down, and prolongs the life of the coil(s). Most electronic ignitions can live with full batt voltage, but not all of them can.dan filipi":sq13kx57 said:The ign switch would bypass it on start to give it full voltage, I presume to provide a hotter spark OR because the starter load while cranking will reduce the available voltage quite a bit.
well said! :thanks:AApple":2v2ilxog said:That's exactly why...to give full batt voltage to the coil while cranking, then lower the voltage while running. On older systems with points, full batt voltage thru the points would burn them much quicker. Dropping the voltage allowed them to survive longer, but still work just fine. Some cars used a resistor wire instead of a resistor block, to do the same thing. Lowering the voltage on the coils keeps the heat down, and prolongs the life of the coil(s). Most electronic ignitions can live with full batt voltage, but not all of them can.dan filipi":2v2ilxog said:The ign switch would bypass it on start to give it full voltage, I presume to provide a hotter spark OR because the starter load while cranking will reduce the available voltage quite a bit.
AApple":574sggaz said:[snip]......... On older systems with points, full batt voltage thru the points would burn them much quicker. Dropping the voltage allowed them to survive longer, but still work just fine......
I wish my '82 coils with the ballast resistor were in better shape.....the wires are split and corroded on the resistor. The other side is.....should I just consider myself lucky that my '81 unit has not melted yet with the '83 engine?dan filipi":20srz31y said:AApple":20srz31y said:[snip]......... On older systems with points, full batt voltage thru the points would burn them much quicker. Dropping the voltage allowed them to survive longer, but still work just fine......
So looking at the 80-81 that do not use a ballast resistor........
It seems like these are the only years that have the problems with the ignitors melting.
What I understand the ignitor does is takes the place of points, it is basically a ON/OFF switch like the points.
If you were to take away the resistor on a points system the life would be greatly reduce so with that in mind are we not seeing the same problem with the ignitors?
If this is true then adding a resistor on these years should prevent the melt down.
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