1976 fj40 coil,ignitor,resistor question or thought verify workkability (1 Viewer)

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I have read so many post about my problem but am looking to simplify if possible. My unit has a coil, ignitor and resistor. I have fire to the points but no fire on high tension lead so something has failed. My quuestion is if I run a 12 volt coil with built in resistor to the coil and hook ignition power to + side of coil and distributor to - side of coil will this run the truck with out burning the points up prematurely ? Is the ignitor a must use? I would think this could work but thought I would ask for more expert thoughts. Thanks in advance.

Jagwarman
 

fj401978

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I'm not one that can help you, but the ones that can are going to want to know what year you have and how much original parts you have, what (that you know of) has been done to it...and maybe some pictures.

Good luck!
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Here's some FSM pics of a 77 ignition coil and spark diag.--maybe helpful--

Ignition coil and spark.jpg


77 fj40 starter wiring2.jpg


77 fj40 starter wiring1.jpg


ignitor insp.jpg
 
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If your coil has an internal resistor it will work. Your points won't last as long because you won't have a condenser in the circuit to suppress the arc when the points open. The first thing I'd check on your original system would be to make sure that the metal bracket that holds the coil is well grounded to the frame. You will get no spark from the igniter if that bracket doesn't see a ground.
 
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Hate to sound too simple but are you sure the rotor is not burned a bad cap or rotor will lose the spark as well.
Cap is new rotor and wires and plugs and points. so that is not the issue. thanks for your thoughts
 
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If your coil has an internal resistor it will work. Your points won't last as long because you won't have a condenser in the circuit to suppress the arc when the points open. The first thing I'd check on your original system would be to make sure that the metal bracket that holds the coil is well grounded to the frame. You will get no spark from the igniter if that bracket doesn't see a ground.
this has been a nut and bolt frame off restoration. since i put it back together i know I had something wired wrong on the coil aperatus because it got hot and was smoking. I thought about the ground but haven't tried grounding it yet. I am really considering the petronix kit with a coil and just throwing that ignitor crap away. I have used petronix kits before and they work great. I will try your idea thanks
 

Coolerman

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this has been a nut and bolt frame off restoration. since i put it back together i know I had something wired wrong on the coil aperatus because it got hot and was smoking. I thought about the ground but haven't tried grounding it yet. I am really considering the petronix kit with a coil and just throwing that ignitor crap away. I have used petronix kits before and they work great. I will try your idea thanks

Hmmm... If you had either the coil or igniter smoking, either, or both, may now be toast. If possible you need to get a known good working coil and igniter to replace the ones you have.
 
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It is not unusual for the ballast resistor to smoke if it has been sitting for a while and accumulated dust. It will run fine with a 12V coil without the resistor. The purpose of the resistor is to improve starting in cold weather by using a 6 volt coil with full battery voltage during starting. The ballast resistor drops the voltage to 6V when running to prevent the coil from burning up. It has no other purpose or detriment.

In summary, if you have the original 6V coil, then you need a ballast resistor. If you have a 12V coil you don't want or need a resistor.
 
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It is not unusual for the ballast resistor to smoke if it has been sitting for a while and accumulated dust. It will run fine with a 12V coil without the resistor. The purpose of the resistor is to improve starting in cold weather by using a 6 volt coil with full battery voltage during starting. The ballast resistor drops the voltage to 6V when running to prevent the coil from burning up. It has no other purpose or detriment.

In summary, if you have the original 6V coil, then you need a ballast resistor. If you have a 12V coil you don't want or need a resistor.

Pin Head, you have helped me in the past and I am looking for your advice again. Today, I was driving my 75 FJ40 and it died, restarted, died, restarted drove it home (1mile) and it died again. I troubleshot everything. Fuel-Good, No Spark, Points opening and closing, rotor button and cap okay. I finally noticed a rusted wire on my Ballast Resistor. This resistor is a 4prong resistor. I scrapped off some rust and touched the wire to the resistor, had someone crank the vehicle and the vehicle started. I removed the connection and vehicle dies, touch it back it continues to run. The resistor is fried, is there a part number or a work around for this resistor? I have seen 2 prong resistors but no 4 prong for my LandCruiser. I have however, found a 4 prong resistor for a dodge truck from the 70's. I believe the ohms to be somewhere like 1.5. Any Suggestions?

Secondly, my transfer case shifter is stuck. I am currently stuck in 2wd and can not move the shifter up or down. I do have a little side to side movement but no engaging of any kind. I have automatic locking hubs. I have tried backing up and trying to shift as im backing and pulling forward. I have popped the clutch to make sure I was actually only in two wheel drive and only the rear tires spun in the loose soil.
 
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I don’t know what a “4 prong” resistor is but it isn’t important. Just get a new ballast resistor.

Try pounding on the 2wd 4wd shifter with a rubber mallet and see if you can persuade it to move.
 

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