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    • #58331

      I am confused. I am wiring up my SV and according to the diagram there are only 2 wires to the coil.
      However, most pics I see have a resistor and multiple wires. Some even show what looks like a condensor
      tied to the + side with the white from the harness and bolted to the body. There is already a condensor in the
      distributor. What is the reason for the resistor and how should it be wired? Thanks for any help.

      Greg D.

    • #66171

      Generally speaking, a resistor would be used to limit the current through the points to increase the life of the points. If a resistor is used, it is usually in series with the wire going to the coil. The only wiring diagram for the Alpine that I have does not show a resistor so I would not put one in.

    • #66172

      Thanks Tom. The factory did not make a wiring schematic for nothing.

    • #66247

      Greg D

      Lucas did at one point use a "ballast" resistor that was wired in series with the coil, this just added more complexity and something additional to fail. I don’t remember seeing this setup on Alpines but it would have been used in the 1967-70 period. Best is to use a standard Lucas coil and no resistor. Not being a fan of "the Prince of Darkness" (as Lucas is sometimes jokingly called) I use a coil for a 1967 Volkswagen or a Petronix coil for a British car. I could write a book about my experience with Joseph Lucas products… most of which is very funny in hindsight.

    • #66249

      I believe we set Greg straight on the SAOCA forum on this topic… series V should have the ballast resistor in series before the coil. There is a separate wire from the starter solenoid to the coil + connector to supply full 12 volts during starting. The wiring diagram does not show everything…


    • #66253

      I have seen people get stuck on this resistor issue in the past. For some reason not all wiring diagrams show the resister circuit. The deal is that when running the resister drops the voltage to the original style coil which doesn’t normally need 12 volts to run properly. This helps preserve the life of the points. In other words, this original coil probably only needs 6 volts to normally function. When you are turning the key and cranking the motor there is a separate wire from the starter solenoid which provides a full 12 volts to the coil to give it a little extra zap and helps the car start. This wire which comes from the starter solenoid goes directly to the same contact on the coil that the resister wire goes and is the one not shown on many wiring diagrams. Countless folks over the years have been scratching their heads trying to solve their starting problems because of a missing wire not shown in the diagram. I think the way its set up if the wire from the solenoid is not installed the coil does not see voltage when the key is turned to the crank position but only as the key is released. Sometimes the car will start as you release the key and the motor is still slightly turning from the starter. However it will start so much better with the wire from the solenoid.

      Dave Reina

    • #66254

      Dave, here is BAD news…. when I worked at General Motors in 1971-73, I gave the engineers at Delco Remy a Lucas 12 volt coil from my 1969 Sunbeam Arrow. They tested it thoroughly and determined that although it was only 3 years old, it was not putting out 1/2 the voltage it was supposed to… that was with 12 volt input. The problem was deteriorated insulation inside the coil (on the windings). So, adding a resistor in the primary coil circuit was not a good idea. What I did was to use a coil for a 1969 Dodge Dart along with a resistor for that coil, I then used a relay to short out the resistor and wired the relay to the starter solenoid. Thus I got 12 volts to a 6 volt coil for starting. That car didn’t just start, it virtually exploded to life when you cranked it. It was by far the best starting British I had ever owned. Dave, by the way, that was the Arrow you were going to buy.

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