Car won't turn off

[mojome]

I have a 68 gto I'm restoring. The car has been moved from points to HEI at some time in its history. The car will start up now, having replaced the alternator, but the car will not shut off when I turn the key off. I was wondering what could be the possable causes.Is it because of the HEI, could it be the timming because that needs to be adjusted, could it be the starter? or is there a fuel shut off that would cause it? Where do I start? thank you for any help

[MrPbody]

When you say "it won't shut off", do you mean it keeps running as normal? Or do you mean it diesels when you turn it off?

If it keeps running as "normal", the primary ignition current is not being disconnected. This could be that the "source" wire is connected from the wrong place. The wire should be "cold" until the key is turned to the "run" position.

If it's just dieseling ("run on"), it means you have too low an octane fuel for the compression ratio. Unless modified, the original engine in a GTO of that era requires 100 octane, and it prefers leaded fuel (race gas today). Add about 30% 110 "race" gas to 70% 93 "premium", and see if that cures it.

Jim

[mojome]

Thanks Jim, I'm running about 91 octane. When I get back home in the spring I'll try adding a octain booster. I guess its just a matter of eliminating the causes one by one. When I turn the key of it will just idel as normal...but then the timings pretty messed up I think.

[MrPbody]

While running and key = "off", can you reach in and remove the wire plugged into the "BAT" terminal on the cap, and the engine quits?

Jim

[mojome]

someone told me something intresting the other day. When I got my GTO the wireing needed some replacing in parts. There was a wire coming of the alternator that was spliced between a piece of what looked like aluminum or something. It was seemed homemade and also there was remnence of a plastic casing that was broken and missing the contents. I was told that there should be a resistor wire in the alternator light wire otherwise the voltage from the alternator will back feed to the ignition circuit. I wonder if I did away with that resistor when I replaced the wire with a new one. I'm really not sure what its supposed to look like or how I can get a hold of a new one. Oh by the way thanks again for all your help.