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Discussion Starter #21
Yes, took it to auto parts store.
plot thickens though - went to start it again, had power to the car, turned to start and everything went dead. Turned key off and on again, everything dead. Disconnected the negative battery terminal and reconnected it. Got power back, went to start and everything dead again. I repeated the process and then got it to start.
so this behavior leads me to believe the solenoid is bad and sticking. Removing power is unsticking or resetting it and then it will intermittently work. Does this seem like good logic from everyone’s else’s perspective?
 

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Yes, took it to auto parts store.
plot thickens though - went to start it again, had power to the car, turned to start and everything went dead. Turned key off and on again, everything dead. Disconnected the negative battery terminal and reconnected it. Got power back, went to start and everything dead again. I repeated the process and then got it to start.
so this behavior leads me to believe the solenoid is bad and sticking. Removing power is unsticking or resetting it and then it will intermittently work. Does this seem like good logic from everyone’s else’s perspective?
It could certainly be the solenoid as they do go due in part to their location close to the exhaust manifold.

But it could be the battery cable. You did not say if your cable ends are good and clean. Do you have the cables with the ends molded on or have you had to cut the cable ends and are using one of those universal replacement ends that you fit the cut/exposed copper cable into and tighten down a plate with 2 bolts to cinch it into place? _ These will corrode badly over time and give poor contact.

Get a battery terminal wire brush that fits over the battery terminal and you rotate it to clean off the oxidized lead and brighten it up. The other end of the cleaner will have a small wire brush that will fit into the battery cable end and will clean it up. I like to put a light layer of grease on the battery terminal to help curb oxidation build up.

Then put your cable on and tighten it down. I have seen where the cable end is too large for the battery post and you cannot tighten the bolt tight enough to get a good squeeze on the battery post. You should be able to tighten down on the nut/bolt to get it secure and still have some space between the battery cable end that is doing the squeezing. If the 2 sides come together and you don't see any space between them, then you may not be getting a secure enough clamp and connection between the cable end and battery post. You should never be able to twist the battery cable back and forth on the battery post once tightened. If you can, then another indicator the battery cable is not clamping correctly and is too large or the battery post is too small.

If that does not work, then I am all for the solenoid replacement and you can check the battery cable connection at the same time.
 

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I had a similar issue recently. My issue turned out to be a poor connection from the wiring harness to the ignition switch. It is pretty easy to remove the ignition switch on '68 and older and test with VOM outside the car. LeMans guys related the best order to diagnose (which I followed)
Even a loose battery cable can make it dead...

so do what you are, Battery verified, then Cables verified, then big grounds, then circuit checks
The under-dash wiring harness / wiring to the starter can be tested if (need a buddy) you take a long 10ga wire and jump directly from Battery positive to the SOLenoid contact on the plug-in connector. (MAKE SURE IN NEUTRAL if is 4 speed.). It should crank if the wiring from the ignition switch to the solenoid is good. It won't start b/c the coil is not powered with the ignition switch out of the car.

The next test is to jump between the SOLenoid contact and BATtery contact locations in the on the plug-in connector. This should also make the starter crank. Again it should not start. This will tell you if the wiring from the fuse block to the ignition switch is good.

If the switch and the 2 circuits are good - then the connection between the plug-in connector and ignition switch is the issue. Clean it up / WD-40 - plug it in tightly and then it should work. At least that is what solved my issue.
Hope this helps.
 
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Sounds like you already know the answer. If you have a battery cable to a junction block and a battery cable to the starter from the junction block, with a large (#8 or #10) wire going to the firewall, then the big red wire is the single-point failure you’re looking for! It’s probably a fusible link (check you’re wiring diagram). Fusible links can get “crispy” in their old age, and do strange things like intermittent failures.
 

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Does dome/courtesy, headlights, etc. depend on the wiring at the starter? I haven't checked wiring down at the starter itself. It's going to require me to pull the starter to check those. I can but wondering if that's the failure point for all power?
you don't need to pull the starter out to check the wires. make sure nothing is grounding out. after you check the battery 1st.
 

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Check those battery cables. I had a similar thing happen once on my 64. The cable appeared to be okay, but when I replaced it (the positive one) the problem disappeared.
 

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Check those battery cables. I had a similar thing happen once on my 64. The cable appeared to be okay, but when I replaced it (the positive one) the problem disappeared.
x2 on this ohm the cable end to end you'd be amazed how much resistance a bit of corrosion inside the wire will do. Ive seen this with both boats and my GTO. I was chasing a break inside the insulation on the power window circut of my 65. thought it was the ground through the hinge... added ground wires back to cowl, still intermittent had a broken wires inside the harness was evident by a higher resitance (ohm reading) than what you'd see on a wire alone
 

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Just stick a screwdriver to the starter wire and the positive. If it cranks its not your starter, positive /negative cable or solenoid. Go fro there.
 

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If you follow your positive lead from your battery terminal it goes directly to the starter. you have threee wires on your starter. 1-goes to the positive lead on your battery. 2. Small thin wire goes to the ignition switch and engages the starter when you turn the key to start. 3. this wire goes to the same lug as the battery cable, this feeds your fuse box. I hope this helps.
I do electrical in homes never done a car but you finally said something that really helps with my knowledge of auto electrical. Always told" oh elec in cars is simple' it is if you know the basic diagram.
Thanks!
 
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