Under Dash Resistor

[Bob56]

Putting the original coil back on from one of those conversions. This is a picture of a car from this forum and also a diagram showing how to hook the wires up. They look totally opposite of each other. The picture shows the red wire going to the right side dash light wire to the left. The diagram shows the opposite. which is correct or does it make a difference

[40cpe]

I say it doesn't make any difference since the current passes through the resistor either way.

[19Fordy]

Here's the 36 wiring diagram.
https://www.google.com/search?q=1936...IVE5J3GxCYwgM:
Trace the wires back to where they come from to make sure. I think 40cpe is correct.

[Seth Swoboda]

Originally Posted by 40cpe

I say it doesn't make any difference since the current passes through the resistor either way.

I agree, the resistor is just a pass through device and does not care what direction the current flows.

[Bob56]

Thanks. Will check the voltage at the coil to be sure

[rotorwrench]

Sponsored Links (Register now to hide all advertisements)

The resistor to coil terminal (resistor output) should only have the wire to the coil on it. The terminal that attaches to the switch should have the red wire from the switch and a wire to feed the instrument panel gauges. Feed for the gauge (or gauges) needs to be on the input side of the resistor so the ignition switch will turn on the instrument/s too. All the other circuits off the buss have their own switches.

Don't forget that a resistor is a load device. The gauges need full voltage to work properly.

[Bob56]

If it makes a difference which is the way it should be

[Darrell Kinnan]

Interest in knowing how much voltage you have going to the coil. Your resistor looks like a reproduction. Thanks D.

[JSeery]

Originally Posted by Bob56

If it makes a difference which is the way it should be

Ballast resistors are not directional, you can connect it either way.

[Bob56]

The picture of the ballast is of a car that I took at last years meet so don't know if it is a repop

[Don Rogers]

Bob56, Here is a diagram that I made for my 35. Notice the main power wire (yellow) going thru the ammeter to the resistor/fuse block. This is the way Henry wired it,

[JSeery]

That's about the only way it can be wired if you want the ammeter to function, but the question was related to the ballast resistor.

[Don Rogers]

I mentioned the yellow wire going thru the ammeter to the terminal block since neither of his diagrams showed any power going to the assembly.

[JSeery]

Agree, but the issue at hand was the resistor, but good additional information.

[gearheadbill]

Are all voltage resistors that are manufactured/sold for our cars equal? Better or worse performance/pricing?

[koates]

Originally Posted by gearheadbill

Are all voltage resistors that are manufactured/sold for our cars equal? Better or worse performance/pricing?

The only resistor to be guaranteed correct is an original ford unit. All others may have various specifications that are not necessarily correct. Their ohms rating cold (.5 ohms) might read the same on an ohm meter but if the resistor wire is different material then it may vary in ohms when it heats up and read differently to the ford one. Regards, Kevin.

[gearheadbill]

Originally Posted by koates

The only resistor to be guaranteed correct is an original ford unit. All others may have various specifications that are not necessarily correct. Their ohms rating cold (.5 ohms) might read the same on an ohm meter but if the resistor wire is different material then it may vary in ohms when it heats up and read differently to the ford one. Regards, Kevin.

Thanks for this info!

[gearheadbill]

Borrowed and temporarily installed a NOS resistor from a friend...says he thinks it's 46-8...but when I measure voltage both TO and then FROM said resistor I get the same 5.8 volts. What am I doing wrong? or is the resistor faulty?

[drolston]

Originally Posted by gearheadbill

Borrowed and temporarily installed a NOS resistor from a friend...says he thinks it's 46-8...but when I measure voltage both TO and then FROM said resistor I get the same 5.8 volts. What am I doing wrong? or is the resistor faulty?

If there is no current flowing through the resistor there is no IR drop and the voltage will read the same on both sides. With the points closed and current flowing through the resistor and coil, you should see about a 2 volt drop across the resistor.

[gearheadbill]

Sounds to me like a test best performed with the car running...all the distributor bits moving etc..