I just acquired my Father's roadster so, I'm not familiar with everything yet. It has a 331 hemi, edelbrock carb and what looks like a typical aftermarket ignition switch. I don't even know if there is anything wrong with it or is it just I'm not familiar with it. In the picture, the green line is where the key is when engine is running(obviously) Red line is where the key is at turned fully into start position. When I turn the key fully to the red line it cranks and cranks but no fire. However, if I just turn the key slightly into the start position, the thin purple line, it cranks and fires up. For now, I just am starting it this way, but I can't help but wonder if something is amiss or am I overthinking it? Thoughts.
Remove the switch and take a good pic. I bet you will have someone give you the part number of a good replacement within a day.
WE=ME, cannot determine which wire goes where, UNLESS, those colors continue to their destinations as prescribed..... A DVM will be your friend........
See if the coil has power while it cranks. I bet it doesn't. We need to know more about the ignition system. Could have a problem, could be wired wrong.
I had the opposite problem with the switch in my '36. Once in a while, it wouldn't crank at all. Since my ring of keys had been hanging from it for over 40K miles, I thought I'd replace it. My local parts store had a Cole/Hersee brand switch, so that's what I used this time. So far, it's fine, but in hind site, I wonder if my neutral safety switch just needs tweeking. We'll see. Gary
If it's a newer style gm motor (65 or so?) You will have a hot wire running from the "I" terminal on the starter to the coil. This powers the coil during cranking then when you let off to the run position the coil is feed thru the ignition switch. Ford did it too on their remote solenoid too but I don't know the yrs. I dont know on the chryslers... ...
Your instincts are correct. It's the switch. There should be very distinct angle separations for the different functions. Like 15 degrees between each detent, not 2 or 3 degrees. If you were to take the old switch apart, I'll bet a dollar that you would see something obviously worn or broken.
Buy a good switch, Cole Hersee or similar. Marine switches are my favorite. If it is made offshore, leave it there and keep looking.
Our OEM 57 Chevy ignition switch like that ^^^^ [except there's no acc position] It relies on the wire from the "R" post on the starter to the coil so it can fire while cranking. Release the key [to run] and the 12v ignition feeds through the ballast resister They did this, so it switches off ALL accessories while cranking and full power to the coil comes from the starter [approx 8.5v after voltage drop loads] ACC on the 57 fusebox has continuity with the Ignition terminal of the switch If your car doesn't have a "R" post on the starter motor, you can bridge a wire from the starter wire [for cranking] to the ignition coil BUT add a 5-8a diode into this wire so it doesn't back-feed from the engine running [and the starter tries to engage]
Universal switch’s do not drop power at the IGN terminal like some auto manufacturers unit’s sometimes do. But yes, a bypass would let the car fire off better, but op’s switch still needs replacing.
He could have the ACC and IGN terminals connected the wrong way round [they both work in run, but the ACC switches off when cranking] A simple test light would verify that
So, using a simple test light, I put the key in the run position. The positive post on the coil had power. However, Moving the test light to the negative post also showed power. Then turning and holding the key to the start position, both posts, pos & neg, showed power. This seems wrong to me. However, I'm not very familiar with this set up. What say you? Each post on the coil has two wires going to them. The only two wires I am certain of is from the distributor. The other two I have to trace out.
Forget about the coil for now and test back of ignition switch like Kerrynzl stated at the IGN and ACC terminal. While there see where those two sets of wiring go to and make a note. Now remove those wires and test light the switch.
If it is point ignition, that simply means that the points were open. If you close the points by bumping the engine over, only the ignition side of the coil will have power.
@Country Joe Yep...... Pull the starter solenoid wire [at the starter] and test the ACC terminal with the switch in cranking position. Also have a good look at the Ignition switch , it could have 2 ignition terminals [like pre-1956 Chevy's] 1 terminal is "run" and the other terminal is "cranking" to bypass the ballast. Chevy labeled theirs IGN1 and IGN2 Kerry
Well you sure woke up the bullshit artists. The truth is that many points era ignitions switches do not supply any power to the coil when cranking depending entirely on the resistor bypass wire to supply power. Simple as that with no bullshit. I do not believe that the switch is bad, just that you have the contact in the switch touching the Ign pin in the switch when you just barely turn it enough to crank. I've seen a number of cars that were missing the bypass wire that would no fire when cranked but fire off when you let off the key and the crank was still spinning. Check to see if it has a bypass wire on it from the solenoid. If there is none or no R post on the solenoid you could install a push button "start" switch from a hot all the time source and supply power to the coil when you crank the engine making it a two hand operation to start the car and even hid the button.
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