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Discussion Starter #1
I just finished a complete rewire on my 66 Lemans. When trying to fire it up the engine starts but as soon as I let off the key it dies. I know there are some other posts about this but I read them all and none of them have what I'm looking for. The engine is a Pontiac 400, it has hei and no balast resistor. I did a little research and found that I needed a wire from the R terminal on my solenoid to the coil terminal on the distributor. So I pulled the ignition wire from the coil and doubled up that wire and the new 12 gauge wire on the solenoid and reconnected to the coil on the distributor and tried to fire it up again and the same problem persists. I'm starting to think it is my ignition switch, although it was fine when I took the whole car apart for restoration about 5 years ago. If this is the case could I replace the ignition lock cylinder or would I have to buy a whole new switch? I'm sure the switch housing is fine since everything electrical on it is working as it should. Does anyone agree that it could be the switch, are there other things to look at etc.? Also how would I go about replacing the lock cylinder if that ends up being what I have to do? Thank you everyone!
 

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Not sure where the thinking started in hooking up the HEI to the "R" terminal on a Pontiac solenoid. That's your problem. The "R" terminal is ONLY activated when you first crank the engine. As soon as you snap the key back, power is disconnected, engine dies.

Just to test, run a jumper wire from the battery to the +/power side of th coil and when you fire it up, see if it continues to run. Pull the wire off, and it'll quit.

You do need 12Volts going to the HEI. Factory points uses a resistor wire to drop voltage so the points do not burn. You can run a wire directly off the ignition switch or simply add a toggle switch under the dash wired for 12V to the coil.

If you do a search in the Google Custom Search engine in the upper right, you should find a few threads on just this problem and how it was solved. :thumbsup:
 

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Discussion Starter #3
I am getting 12v to the hei through the ignition coil wire at the fuse box. I found an article on americanautowire.com that talked about converting from a points distributor to hei and one of the things it mentions is an override wire from the solenoid R terminal to the coil terminal doubled up with the 12v feed wire. So that is where that came from. So I figured I'd try it since the engine won't keep running the way it was. But it did not solve anything, now I'm here.
 

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Well do you have a link to such threads because I don't see them?
If you do a search for "ignition switch" you can find a few that relate to your situation. I assume you have a wiring diagram for your car. If I am correct from what I read, you should have had 2 wires going to the coil+ side - one is the cloth covered resistor wire which works in the "Run" position of the key and reduces 12Volts down to about 9Volts so as not to burn up the points, while the other wire is the 12Volt power wire which works when you turn the key to the "Start" position to give the coil full 12Volts for better starting.

As soon as you snap the key back to the "Run" position, the 12Volt wire is disconnected at the key switch and the engine now runs off the resistor wire which is also connected to the key switch. The "R" terminal on the solenoid does the same thing that the 12Volt wire does which comes off the key switch - and when you snap the key to the "Run" position, the 12Volts is disconnected at the "R" terminal.

That said, you want to trace the wire from your ignition switch using your wiring diagram (or use a test light to determine which terminal is the "Run" position) and use this to hook to the HEI. You could keep the wire you now have from the "R" terminal going to the HEI as your "Start" wire as it would function just like the "Start" wire normally used by the ignition switch. However, you want to eliminate the resistor wire that would normally be used on the 1966 points distributor which you have replaced with the HEI. In its place, just run a wire from the ignition switch "RUN" position to the HEI.

Some will remove the resistor wire at the firewall junction block and replace it (engine compartment side) with a 14 gauge copper wire at that point going to the coil to give you 12Volts. Personally, I think it easier to go from the ignition switch directly to the HEI, but if you wanted it to look original, then replace the length of wire at the firewall junction block to the HEI.
 

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Discussion Starter #8
Thanks everyone. It's been a few weeks and I've been busy with other things but I got the issue taken care of. Like jim said I ran a wire from ign1 on switch to the coil and now it runs as should. Just curious, should I install an inline fuse on that wire or just leave it the way it is? Thanks again all!
 

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Thanks everyone. It's been a few weeks and I've been busy with other things but I got the issue taken care of. Like jim said I ran a wire from ign1 on switch to the coil and now it runs as should. Just curious, should I install an inline fuse on that wire or just leave it the way it is? Thanks again all!
Hooray! Success in getting it sorted out. I would not bother with an inline fuse. I would think that the main 12V power wire that energizes the ignition switch is already tied into the fuse block. :thumbsup:
 
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