resistor under dash 1933
 

There is a open coil resistor under the dash that is rusted and broken. The former owner has a jumper across the two ends. What is this for ? I found a wiring diagram that leads me to think it is for the ignition coil. Thanks

Re: resistor under dash 1933
 

Resistor limits current to points. So extends life of points & coil.

Re: resistor under dash 1933
 

It is for the coil - you'll definitely want one (or a suitable replacement) as it prevents over-voltage to the coil and burning your points.

Re: resistor under dash 1933
 

The resistor should have a cage around it and should measure 0.5 to 0.6 Ohm. Sounds as if the PO was running a different coil than the Ford. If so the resistor value may change from Fords.

Re: resistor under dash 1933
 

The original resistor was designed to work with the original type Ford coil (which was mounted atop the Ford distributor). If the previous owner bypassed this resistor he may have changed to a remote mounted 6V coil, which would handle the full 6 volt input no problem. If the vehicle is again running with an original coil, you should replace the old damaged one with a new one. Part number is 18-12250. We and a few other vendors stock a high quality USA made part.

Re: resistor under dash 1933
 

From what I've read about this, the resistor is especially important to keep from burning the points by reducing the voltage going to them to 4 volts.

Re: resistor under dash 1933
 

Thanks to all, I ordered one from third gen parts. The P O had jumped the resistor and caused the coil to overheat and explode.