Has anybody installed the Pertronix power relay for the Pertronix ignitor electronic ignition?

I have installed one on my 63 car and as per the instructions I had to also install the isolation diode in the wire from number 4 terminal on the regulator to stop current back feeding to the new relay which would keep the engine running with the ignition key off. I now find that when first switching on the ignition (before cranking), the GEN light is lit but it's only very dim. Also when the engine is running the GEN light stays on, but it's very dim. (The charge circuit from generator to battery is working correctly).

Is this now correct and something I've got to accept?

I'd like to know other people's experiences please?


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I had run the Ignitor II 91181 for about a decade then the Ignitor III 71181 sine around 2012 and neither requir installation of an "isolation diode". There is mention of a "diode fix" for other applications in the instructions manual where it states:

"Will the electronic shift assist in an OMC boat work with the Ignitor III?
A. The Ignitor III will work with all OMC stern-drive applications, when our “diode fix” is used. If you’ve purchased a kit that didn’t include the “diode fix” diagram, call our tech line."

My guess is 1) you are using the incorrect Pertronix unit or 2) you bought a kit from someone that included this "diode fix" kit (which I have never seen), or 3) Pertronix has released a newer unit that requires this addition installation step.   

Give the fact Pertronix simplified things from the II to the III version (i.e. distributor doesn't have to come out) and am not thinking option 3 is viable ... but again it has been 12 years since I last installed one. Either way,  installation of both the 91181 II version and the 71181 III was very straight forward with the understanding the II took considerably more time having to remove the distributor. The III was like a 30 minute install job. 

It would help if you listed your specific Pertronix Series and Model #.

Just to clarify I haven't installed the Pertronix ignitor yet. I started with the power relay first to ensure I had full 12v feed to the ignitor as per the instructions. My Pertronix model number is 1181LS. I will attached pictures of the instructions and also from the Pertronix power relay kit as well.


That is an ignitor I series unit. The oldest unit and one I think you would want to skip over once you read our Pertronix Ignitor Ignition & Flamethrower I, II, and III Compar...  Help Page.

You will still need to get a "switched" 12 volt source to fuse box. There is a rubber grommet at top center rear of engine used for cranking harness. You can run your wire through here. See picture below:

There is also a rubber grommet on left just to left and below the left driver hood hinge for routing cruise control lines, etc. 

If you pop the dash pad off you will see where the brown resister wire connect to the "pink" ignition circuit. You can tap in to that pink ignition circuit or go to the switched lead on side of fuse box.  If you go to the fuse box you will see a connector to the right for ACC (Accessories) This is the one you want to use as the one above it for Window is 12 volts full time. If it is not being used you can just connect directly to it, or makes a Y connector, use a fuse tap-in, wire tap-in, etc. But this is where you need to connect. 

There are also empty slots on the large bulkhead connector  (large white connector) that carries the forward lamp harness, etc into the firewall which could be used if you wanted to make things really look factory. I had considered doing that but have never gotten around to i.

Thanks Jason I will look at the Pertronix Ignition comparison page.

I have found the ACC fuse terminal on the side of the box and although it is being used I can tap into that ok. See attached picture. 

I don't have a rubber grommet under the driver's side hood hinge as my car does not have cruise control. I am reluctant to remove the dash pad as I've not done that before and I'm concerned about breaking something on removal or replacement. I will look for the large builkhead connector up under the dash and see how easy it would be to get a wire onto it.


The cranking harness grommet dead center behind engine is probably your best route.

You should see a rubber plug over on left driver side even if not used. It is just another option for running wires, etc into the cabin.  See oval plug/grommet below. 64's have these but always always have a cad plated metal retainer as seen in 2nd picture below. 

If I use the cranking harness grommet can I get to it up under the dash without removing the pad?

With lower instrument panel (dash) cover below steering column removed and with a good light you should be able to fish a wire through grommet and see it coming through and pull toward the fuse box. 

Just to note, The dash pad comes out relatively easy if you take your time and focus on what you are doing. There is a help page on removal at Dash Pad Removal.   

Personally, if I were fishing a wire into the cabin of my 64 CDV I would not not remove the dash either ... pretty sure you will see it coming through somewhere looking up in the area from below with a good headlamp on.

If it doesn't go through far before wire hits other wires, etc. you could also tape it to a straightened wire clothes hanger and gently fish it through. I would cover the tip of wire with several layers of electrical tape, and have it gently bent downward gently thread into the cabin. If you just jab it in you could end up punching into a duct or something worse.  

I've managed to get a wire through the cranking harness grommet and connected it to the ACC switched terminal. When connected to the coil I still got the same results with the GEN light. So I removed the relay, wiring and diode and reinstalled the resistance wire to the coil, started the engine and the GEN light was still on. I got a reply from Pertronix saying that I should not connect 12v to the original coil as it's only designed to take 9 - 10v and I could damage it. I then replaced the coil with an old one I had and still got the same results with the engine running. After more testing I've now found that the battery is not being charged with the engine running. So it looks like I've damaged either the generator or regulator and the GEN light was doing it's job in trying to tell me there was no charge. It seems I should have installed the Pertronix coil and ignitor first before getting a 12v supply to them. (For info' the Pertronix support guy was very helpful in trying to solve my problem). I've now got to do some more testing to see whether it's the generator or regulator that has gone faulty. 

It seems the generator has gone faulty and only putting out 2.0v. I would guess I've damaged the internal diodes inside the rectifier.

Remove the isolation diode from the scene. Run a switch power wire to the coil and that will solve your problem. You can remove the resistor wire but you will need to take the dash pad off to access the ignition wire harness where it is spliced into it. Just resolder the new wire into the old harness.  Or run the new wire from the fuse box. There is a terminal on the side that is switched. 

I can understand what you are saying Russ. If I I run a new switched wire from the fuse box, what's the best way to get it through the fire wall to the coil?

I'm attaching pictures of the Pertronix instructions to clarify things, I hope.  




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