The 1947 - Present Chevrolet & GMC Truck Message Board Network

Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > General Truck Forums > Electrical


Thread Tools Display Modes
Old 06-03-2018, 02:13 PM   #1
Registered User
nikwho's Avatar
Join Date: Apr 2010
Location: Flagstaff, AZ
Posts: 743
Can anyone tell me the difference between "Ign 1" & "Ign 2" on my ignition switch?

Hello all,
So, years ago I rewired my '59 Apache entirely, using a Rebel Wire harness. The harness was great and seemed easy enough to install. Back then I had used a generic ignition switch, that I likely bought from NAPA. It's super basic, with a Bat power terminal, an Ignition terminal, Acc terminal and a Start terminal. Seemed simple enough, and per the Rebel Wire directions, I tied the Ign. Sw. coil (Pink) & Ign. Sw. Acc (Orange) wires together and connected to the ignition terminal on the back of the switch.

Well, I just got this truck back, after it being with my dad for the past 6 years and decided that I didn't like the cheapo generic ignition switch, so I bought a new ignition switch setup from LMC truck, that is correct for my '59. It has two ignition terminals on the truck, and without putting too much thought into it, I seperated the two wires and connected the coil wire to "Ign 1" & Acc wire to "Ign 2", thinking (logically, in my mind, with no research, foolishly) that the switch would send power to "Ign 1" during starting, while cutting
Power to the accessories through "Ign 2". I don't know why I came to this assertion so confidently, but I hooked it up and cranked it over, to see how my new ignition switch worked. Oh, by the way, this truck has an HEI distributor.

What I have ended up with is the following signs and symptoms; While cranking, my ignition coil wire is not seeing 12v, as it will crank and crank and crank, but will only start once I release the switch back to the run position! So, if I crank it for just a second and let off, it will fire right up, as the engine is coasting as the starter is disengaged. That's a good sign that my Engine's ignition and carburetion systems are tuned well, but not right! So, my coil is seeing 12v when I'm run, but not the start position. That's a simple enough solution, it would seem.

However, what's confusing me is this; Though the truck will start easily enough, by cranking and releasing the switch, when I **** the truck OFF, I get a loud grinding nasty noise from the starter! Almost as if the starter is trying
to re-engage as I shut the truck off. So, my though initially was that I need to just switch the two wires between the two terminals, but the starter making the nasty grinding noise upon shut down complicates it somewhat. I have not had much time to diagnose since, as I am stuck at work now.

So, thoughts? I was thinking that I should just reconnect the two wires together and try on "Ign 1" position. I'm thinking now that rather than "Ign 2" being for accessories, to cut power to everything but ignition and starter while cranking, that it is actually intended for the original floor starter lever!

So, I was hopeful that since the switch came with no information about the two ignition terminals, that someone here would be able to explain them to me a bit? I also had the thought that it might be fun to utilize an electric foot switch to start the truck, that could function as a sort of anti-theft device, and be similar in using your foot to start the engine. I believe that the original setup was a mechanical pedal that you pushed, that connected to the starter, rather than an electric switch. Anyway, my main goal is just to get power to my ignition during cranking and to resolve my nasty grinding noise from the starter when shutting the engine down. I have NOT yet checked to see if the starter is remaining engaged from the moment it starts, to the moment that I shut it off, but I have not heard the starter sound like it was remaining engaged, though the truck's exhaust is fairly loud, being headers into a couple of feet of 2.5" tubing, through a couple of two chamber turbo mufflers, then turndowns near the back of the cab, so there's not a lot of audible diagnostics going on with it running.

Thoughts, anyone?

Thanks much,
Attached Images
'68 GMC - BBC/TH400
'59 Apache - SBC/700r4
'53 GMC 350/th350, S-10 swap & 3 linked - SOLD...
nikwho is offline   Reply With Quote
Old 06-03-2018, 06:36 PM   #2
Senior Member
dmjlambert's Avatar
Join Date: Apr 2016
Location: Cypress, TX
Posts: 1,200
Re: Can anyone tell me the difference between "Ign 1" & "Ign 2" on my ignition switch

I just know general info but no specific knowledge of this switch. So perhaps others will join in and give more info.

The switch in the accessory position is supposed to power accessories but not the distributor.
The switch in the on position is supposed to power accessories and the distributor.
If the switch in the start position does not power the distributor, that was OK with the points distributor/coil setup, because the coil received its power from the starter during start, and when the starter was disengaged it would then get power from the on position of the switch through a resistor wire or regular wire with inline resistor. So the simple fix for HEI would be to connect the distributor power wire to both the switch and the starter. If you have a conventional starter, I believe the outboard screw (most toward the passenger side of truck) is the one that provides coil power during start.

I don't know what to think of the grinding from the starter in off.
dmjlambert is offline   Reply With Quote


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

All times are GMT -4. The time now is 09:53 AM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2019, vBulletin Solutions Inc.
Copyright 1997-2013