Re: Wiring on ignition coil - 1949 model 2365

Posted by HH56 On 2014/8/8 21:31:13

The extra wire is probably the overdrive ign cut out. If you have the R9 OD it goes to terminal 2 of the large 6 terminal overdrive relay. Your 49 should have the R11 OD so it would go to one of the upper terminals on the kickdown switch.

The wire is part of a circuit operated by contacts in the solenoid and relay if the R9, or the solenoid and kickdown switch if the R11. The purpose is to kill the spark for a few milliseconds so the engine loses power. When kickdown is called for, the circuit is completed & dist terminal on coil is shorted to ground so the spark misses a few beats and torque drops. During that time the solenoid spring can retract the plunger. Once the solenoid plunger is completely retracted, its contacts open and spark is restored.

The circuit has been known to cause issues if a wire shorted or one of the switches or contacts stick. If the car was working fine before the coil change, chances are the circuit is OK. It won't hurt to temporarily disconnect the wire to completely rule out any OD problems causing the no start.

If the car has sat for a long time or the ign was on for a long period with engine stopped while points were closed, there is a good chance the points have oxidized. Changing them or at least touching up the point surfaces with a contact burnisher or point file would be a good start. If you have been working in the dist, also make sure any of the old fabric covered wires that may be between the points and outside terminal has not lost insulation and shorted.

A low condition in the battery, corroded battery connections, or not having the large 0 or 00ga 6v battery cables are other persistent reasons the spark is weak.