Does anyone know why the ign- wire that goes to the back of the of the ign switch is melted?Now I’m having a problem where the resistance wire going to the coil is getting hot and smoking!I realize I prob have a short in resistance wire bec when I moved it the car [censored] off.I have Mallory ign e-Spark and msd blaster 2.If the wire is the problem can I cut out resistance wire and run a reg wire?
Sounds to me like the coil may be hooked up wrong. There's only supposed to be about 9 volts going through that resister wire. It is used on all 12 volt cars with points to drop the voltage to protect the points during starting. I'm not familiar with the Mallory e-Spark. If you are not running points any longer you will want 12 volts going from the ignition switch to the coil. That can be done by adding the 12 volt wire or by using a relay which would be opened by the resister wire to pick up a 12 volt source. I hope that's some help.
The resistance wire replaces the ballast resistor we used to see in older cars. It is actually used when the car is running not starting. The yellow wire that comes up from the starter supplies full battery voltage, via the thick purple start wire from the switch to the starter solenoid, to the coil for starting. Once the engine starts the resistance wire supplies a lower voltage for running. Only eight to nine volts is supplied to the coil to keep it from failing due to over heating. When the starter motor is engaged it draws a lot of power from the battery resulting in a lower voltage available to the coil. Full battery (reduced due to starter motor) voltage is supplied to the coil during starting as the voltage from the resistance wire would be reduced even more during starting, perhaps low enough to not fire the plugs enough to start. A higher voltage at the coil for the brief time it takes to start the engine isn't much of a threat to overheat the coil, but running the coil full time at alternator voltage of 14.8 volts is. Some coils have an internal resistance eliminating the need for a ballast resistor.
Sounds like a short to ground, perhaps it's insulation is worn and the wire is touching a part of the body and grounding. Or it could be as Doug suggests, the circuit grounding at the coil. I am also not familiar with the Mallory E start, but it sounds like an electronic ignition which would require 12 plus volts. If so and your ignition wire is already burn out you can replace it with a non insulated wire that will supply battery voltage to the coil. If it is a modification that converts points to a module type ignition you still may need the resistance wire. If so you will have to find a resistance wire to replace the burned out one, or use a regular wire and install a ballast resistor. The ignition system you have may require a specialized coil used for that system only, the blaster 2 may be the problem.
Did you install the E ignition yourself or did you buy the car with that already installed? Did the car run well before and this is just a problem that has recently come up?
Do you have the ignition wire attached to the pos + terminal of the coil? Do you have any other wires attached to the same pos + terminal that could be grounding?
Bluebird 428, yours is a great definition of how the original ignition works. When changing to a later pointless ignition I have used the resistor wire to activate a relay to give a full 12 volts to the later pointless ignition and it has worked well, but your description is absolutely correct for points!
Gus - Thanks, but remember I'm not an expert at this, I'm just putting my opinion out there.
cme469 - That is the method I used when I installed an HEI. The original resistance wire supplies plenty of voltage for the control circuit to switch the relay on and off, and the power circuit running from a junction supplies battery voltage at start up and full 14.8 volts when running. That eliminates the yellow wire going to the coil from the R stud on the starter.
Mark - If you have been running with this set up for a while and this problem has just started, check for a short to ground in the wire itself as well as a shorted primary winding in the coil. From what I've been led to believe pre around 2001 MSD coils were made in the USA. After that the red ones were made in Mexico. The Mexico ones were rumored to have problems with shorted windings. The old ones had a ribbed body the newer ones are smooth. If the windings are starting to shorten out it may cause the coil to completely fail or cause wiring to pass too much current and over heat. I just took a brand new MSD Blaster 2, PN 8202 out of the box and tested the windings. It's made in China. The primary winding has a resistance of 0.7 ohms. the secondary has 5,220 ohms. Specs are 0.7 ohms and 4,500 ohms. The Blaster 2 is made for use with a MSD ignition box, if used with a normal points distributor it need a 0.8 ohm ballast resistor. Hope that helps.