Ok guys I couldnt find my older post with my other wiring problems but heres a new one. I have a 66 F-100 Camper Special, Custom Cab and I bought a painless wiring harness and I am installing it slowly because i know nothing about wiring. I've got a two questions right now on my truck do i have an balast resistor? Now this wiring harness has the option of using a balast resistor. What does a balast resistor do and what are the benifits or drawbacks of having one? If you guys have any other helpfull hints that would be great to?

Thanks Alot!!!, Brannon

 

Brannon: The ballast resistor has the primary function to reduce the voltage to the points while the engine is running. If a full 12v is going to the points, they will burn up real fast. Keep in mind, that there are usually 2 circuits to the points, one for the reduced volts, and one for a full 12v - this second circuit is only used during cranking to improve spark to help the engine get started. Also, bear in mind that while only 1 wire goes to the points, the ignition switch is designed to allow 12v to the points while cranking (Start), and 6v while on (Run).
Check your voltage to the points to find out if you have a resistor or not.
This process assumes you have good wires, a sound ignition switch, and good electrical connections and grounds.
Disconnect the wires from the points.
Measure the voltage across the battery.
Turn the ignition to Run, but not to Start.
Measure the voltage at the wires to the points.
If voltage at the wires is about the same at what you have at the battery, you do not have a resistor.
If voltaqge is about half or less, you DO have a resistor.
Continue with this check:
On the starter solenoid, remove the small wire closest to the battery cable (NOT the one going from the solenoid to the starter.)
Have an assistant turn and hold the the key to Start.
Measure the voltage at the points.
If voltage is about the same as at the battery with the key at Start (but more than at Run), then you DO have a resistor. It is usually a part of the wiring harness, but often is a ceramic block mounted somewhere to the firewall.
Finally, the second connector at the starter solenoid, the one next to the starter cable, is the source for 12v to the points. It is only active when the solenoid is activated, and the starter is cranking.
Hope this helps, and I sure hope it makes sense!

 

Thanks alot John that helped a ton. My next question is whats a tachometer and do i have one? Thanks again for all the help.

Brannon

 

Ok sorry guys I had a brain fart i know what a tachometer is i was just spacing sorry! Brannon

 

Ok i got another question where my oil pressure sending unit is there is a post and i have a wire for that but down a little bit on the oil pressure sending unit there is another post where a wire used to be connected. Do i need to connect something here or not? I have a picture of it but i dont know how to put it on here. Thanks alot!! Brannon :-)