Merc Ballast Resistor wire location question.

[Boomyal]

I'm asking this for a friend who is installing a Pertronix on his Merc setup. It is a mid to late 80's 4 cylinder GM motor, I assume with an alternator.<br /><br />If this is enough info where can he find the Ballast resistor wire so that he can eliminate it?<br /><br />Would you just cut it out and splice in a new wire?

 

[rbezdon]

Re: Merc Ballast Resistor wire location question.

Boom, it is highly likely the ballast resistor is the wire coming from the ignitio controlled +12 to the coil +. It is sometimes purple with a stripe of some kind. I know the OMCs in the 80s used the resistor wire instead of the external physical resistor. This is what cars used to use as well (for the most part). The way to check it is to use the ohm meter on your DVM and measure the resistance from the coil + to any ignition controlled +12 wire (usually purple). If it measures in the range of 2 or 3 ohms the resistor is OK.

 

[Laddies]

Re: Merc Ballast Resistor wire location question.

Most of Mercrusiers resistor wires are in the harness and run between the electric choke and the coil

 

[qaztwo]

Re: Merc Ballast Resistor wire location question.

thats the way mine is, choke to coil. Believe the wire is white with a red strip, things could have changed in 30yrs though. He can either get a coil that can handle 12 volts and run a separat 12v wire to the coil and hook the pertronix to the coil, or run a separat 12v wire to the pertronic unit. I just bought the pertronix II came with that info. good luck

 

[rbezdon]

Re: Merc Ballast Resistor wire location question.

Boom, as I said, the resistor wire comes from the +12V switched by the ignition which is the source for most electric chokes. In my OMC, I don't have an electric choke so the resistor wire comes from the ESA +12. All elecrically the same, you just need to look at the coil + and see the sires connected. One will go to the starter solenoid for the ballast resistor bypass and the other will be the resistor wire going to the +12 which is switched by the ignition. This wire will have a stripe and will be your resistor wire.