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-   -   Starts with button, not key (https://6066gmcclub.com/showthread.php?t=51884)

OldRed November 9th, 2025 05:30 PM

Starts with button, not key
 
I completed the swap for my 305 V6 distributor to an HEI as written up on Jolly's site. I installed an aftermarket carb from Amazon (single barrel is a single barrel) and a new gas pedal with a throttle cable to simplify the linkage based on what was under my hood. I installed new wires, plugs, set the timing to roughly 5 degrees BTDC, and used a vacuum gauge to tune the carb as best as I could. I have an inline electric fuel pump, completely bypassed the manual pump and simply toggle on the inline fuel pump a few seconds before I try to start the truck.

I am able to turn my key to on, switch on the fuel pump, and place a starter button on the solenoid and start the truck no problem. I mean it fires RIGHT up, like I am almost surprised every time at how quickly it will start.

However, if I try to use the key inside the truck, it just cranks and does not want to start. I ran a new wire from the fuse box to the distributor, so that it could handle the appropriate flow of electricity to start/run. I never got around to hooking up the tach wire on the distributor though. I did not think that would cause an issue, but maybe it does? Is it possible the engine could run with the tach hooked up, and not the power wire to the distributor? And that's why it only starts when jumping the starter solenoid? That doesn't make sense in my brain but stranger things have happened. Or maybe my ignition switch is bad? When I turn the key though the starter does crank, which I feel like indicates there's a drop in power or something.

I'm open to any suggestions on things to look at or maybe just direction on where to start. I've also been contemplating replacing the fuse panel as mine is not in the best shape, and that could be causing an issue internally that I can't see.

Thanks for the help!

OldRed November 9th, 2025 08:01 PM

Re: Starts with button, not key
 
I can't figure out how to edit my previous post...but I figured I'd mention:

Where the power comes out of the fuse box that goes hot with ignition, I have it split with one wire going to a toggle switch for the fuel pump, and the other wire going to the distributor. I'm thinking maybe I am not able to get enough power directly to the distributor that way when the switch turns things over?

I love electrical things. :banghead:

James November 9th, 2025 08:07 PM

Re: Starts with button, not key
 
Quote:

Originally Posted by OldRed (Post 79126)
However, if I try to use the key inside the truck, it just cranks and does not want to start.!

It's time for a multimeter. Connect the meter to the starter start stud and see if the is voltage there (probable won't be base on your description) while holding the switch in start. Then Proceed to the firewall connector (I believe it will be on the firewall behind where the original coil use to be). You can back pin it and check for power while holding the switch in start. If still no power, pulling the switch out and back pinning the switch while holding it in start. If still no power, it look like a bad switch. Unplugging the connector from the switch, you could jumper the switch connector to see if the starter turn over. If it does then the switch is bad.

Quote:

Originally Posted by OldRed (Post 79126)
I ran a new wire from the fuse box to the distributor, so that it could handle the appropriate flow of electricity to start/run. I never got around to hooking up the tach wire on the distributor though.

The wire that run from the firewall connector to the original coil is a resistor wire. On my truck I depinned that wire from the connector and installed a solid wire so the power come directly from the ignition switch to the distributor.

If the tach works with the point distributor before, then connecting it to the HEI will be no problem, there is a terminal there just for that and I think the cap show the labeling for the pin out (should be the only one not being use).

OldRed November 10th, 2025 02:19 AM

Re: Starts with button, not key
 
Quote:

Originally Posted by James (Post 79128)
It's time for a multimeter. Connect the meter to the starter start stud and see if the is voltage there (probable won't be base on your description) while holding the switch in start. Then Proceed to the firewall connector (I believe it will be on the firewall behind where the original coil use to be). You can back pin it and check for power while holding the switch in start. If still no power, pulling the switch out and back pinning the switch while holding it in start. If still no power, it look like a bad switch. Unplugging the connector from the switch, you could jumper the switch connector to see if the starter turn over. If it does then the switch is bad.



The wire that run from the firewall connector to the original coil is a resistor wire. On my truck I depinned that wire from the connector and installed a solid wire so the power come directly from the ignition switch to the distributor.

If the tach works with the point distributor before, then connecting it to the HEI will be no problem, there is a terminal there just for that and I think the cap show the labeling for the pin out (should be the only one not being use).

James,

I decided to just run my wire from the distributor directly to the ignition key as you described and my truck started right up! So thank you for the response, I don't know why I didn't do it that way from the start. I will try hooking up the tach wire here soon

Thanks again!


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