Ignition Coil

I purchased an ignition coil from Rock Auto that says it was for my 1967 cj5 F134. Printed on the side of it, it says it needs a 12 V Resistor installed to work properly, I'm not familiar with what exactly this means. can you guys help me out?

 

Found on the firewall.

Coil is designed to run at less than twelve volts, so a resistor is put in the circuit. In some vehicles this allows a bypass to give the coil full voltage during cranking, then drop the voltage for normal running.

 

More Information for STANDARD MOTOR PRODUCTS UC12T
This is the coil I purchased

I know the way my jeep is currently set up it has nothing that looks like what is posted in PeteL photo.

 

All I have is a hot wire running from the starter to the ignition switch and then a hot wire running to the coil, that's it

 

you need a ballast resistor as seen in petes photo

 

Okay, so is this something I can just go to oreillys and get?

 

But can I not just put an external resistor on it and use it, or just I just return it and get the right one?

 

I'd get the resistor. It's easier to troubleshoot a problem if you can seperate components and test individually.

It was $11 when I bought one last.
Anyone remember when? Haha

http://www.earlycj5.com/xf_cj5/inde...ith-a-happy-ending.115928/page-7#post-1223220

 

Different resistor (ohm) values for different coils and vehicles. Need to know which one.

Without it your points will burn rapidly.

 

Mine's on the firewall real close to the coil.

 

Now then. Call Rock Auto. Ask them which ballast resistor matches to your coil. Buy it. It mounts on the firewall as close to the coil as you can get. You may even find the original mounting holes. Wiring is from the ignition switch “IGN” or “START” post to one terminal of the resistor. From the other terminal of the resistor to the “+” terminal on the coil.

 

Fwiw the coil with the internal resistor is Omix-Ada 17247.02 Ignition Coil. Amazon has it for 34.00.

 

I got mine from Walcks 12 Volt Coil With Internal Ballast Resistor - Walck's Four Wheel Drive for $30 and it has the internal. My 58 did NOT have mounting holes for a resistor and according to Walcks the 4 cyl all had internal in that era.

 

Yeah, I would too. My experience with this is that a generic ballast resistor will work fine - you don't need to worry about matching the resistance exactly. Standard RU37 or equivalent More Information for STANDARD MOTOR PRODUCTS RU37 $5 at RockAuto. I picked it from a '70s Dodge with a 318, but it applies to many many different applications, including '62-73 Jeep. When I worked parts counter, we sold a lot of these as a generic replacement for any ballast resistor application.

I avoid Omix-Ada parts unless there is no alternative.

 

I went by oreillys this morning, every coil they could get needed an external resistor.. so I ordered the resistor, will be here tuesday... I hate have oreillys as my only parts store!

 

I use my jeep for snow plowing. I "upgraded" to a coil requiring a resistor, and have a "bypass" toggle switch to jump out the resistor when it is cold and the battery voltage is low. The load of the starter reduces the available voltage to the coil while the starter is engaged. "bypassing" the ballast resistor gives a boost to the coil voltage. I have the 4 cyl engine, generator (the plow pump is mounted to the generator) and points ignition.