1972 Deville, Strange Electrical Problem..

[Coupe Deville]

Hello everyone, its been a long time since I've been on here but now I'm back with a question.

I got my project 72' Coupe Deville running reliably a few weeks ago. It has been running fine.

So the other day, (1/17/16) I went out to the car, I had not started it in about a week, I hook up the battery cables and get in and turn the key. The starter clicked, and all of the power went out. Interior lights and everything. So I figured, loose battery cables. Since I disconnect the battery whenever I leave the car for an extended time. So I cleaned up the cables and reconnected them tightly. Lights come back on and try to crank... Same thing happens. "Click" at the starter and all power goes out. So i just left the key in the run position for a about 2 minuets while I was trying to think about what is happening and randomly everything comes back on?? So I try to start it and it happens all over again. So I replaced the starter with a brand new one, it does the exact same thing. I'm at a loss. So it will not start, and I have intermintent power failure to everything. I thought fusible link but i think it cant be that because the power loss is intermittent. And if the fusible link blew out somehow, that I would have no power for good. Any thoughts? I'm confused myself.
As always, thank you for your suggestions!

-Gavin

[Evan Wojtkiewicz]

How old's your battery? Trying to get my '67 out of winter storage last year I had the same issue. Jumping the battery didn't do anything until a tow truck came and he jumped it with his heavy-duty charger. Long story short, it was definitely the battery in that case. It takes a lot of power to start these things.

[bcroe]

So the other day, (1/17/16) I went out to the car, I had not started it in about a week, I hook up the battery cables and get in and turn the key. The starter clicked, and all of the power went out. Interior lights and everything. So I figured, loose battery cables. Since I disconnect the battery whenever I leave the car for an extended time. So I cleaned up the cables and reconnected them tightly. Lights come back on and try to crank... Same thing happens. "Click" at the starter and all power goes out.    -Gavin   

If the lights go out, its not the starter, its a battery feed problem.  Since
you checked the bat terminals already, see if there are any junctions
that feed both lights & starter.  Or put a test light directly on the battery.
If it goes out too, you have a defective battery internal connection. 
Bruce Roe

[bill06447]

Sounds to me like a bad connection or battery, as previously mentioned. If you are using those bolt-on battery cable terminal ends, DON'T. They are a waste of time money and aggravation and not a substitute for soldered/swaged cable ends.

Bill

[Julien Abrahams]

I'd put my money on the battery. I had the same problem with another car once, and it turned ut to be the battery which was shot. A battery lasts about 10 years, (max.) in my experience.

[TJ Hopland]

In that era there was 3 fusible links in the feed side of things.  All 3 wires went to a single ring terminal on the big battery terminal at the starter.    There was around 18" of fusible link wires before they went to regular wires and joined one of the big bundles of wire.   73 had a 5 or 6 pin connector at that point so I assume a 72 did also.  At some point they got rid of this connector so I assume it was a problem spot.   Its very close to the exhaust and low enough it can get road crap on it so its a good place to look when you have issues.

In that harness / connector there were 5 wires.   One wire is the start wire from the key that engages the starter.  The other regular wire is from the I terminal on the solenoid and goes to the + terminal on the ignition coil.  That leave the 3 link wires.   One feeds direct to the headlight switch.  One feeds the fuse box for the stuff that is always on.  The last one feeds the rest of the fuse box via the key for the stuff that comes on with the key.   

If its still doing it or next time take note of what is still working.   Knowing those 3 circuits may help narrow it down.  IF you are indeed loosing everything that points to a fault before they split into those 3 circuits.   Be sure to try the headlights since those don't run through the fuse box or key and try something else that does not run through the key side of the fuse box.   IF you find that its only key stuff it could be in that feed wire or perhaps the ignition switch itself.

[Coupe Deville]

Sounds to me like a bad connection or battery, as previously mentioned. If you are using those bolt-on battery cable terminal ends, DON'T. They are a waste of time money and aggravation and not a substitute for soldered/swaged cable ends.

Bill

You called it Bill.. Bolt on terminals were rusted on the inside tab. They looked perfectly fine from the outside and I tightened them up. But I could physically see the battery cable arcing to the post. Took it apart, all rusted out. Thank you for providing a solution. And thank you to everyone els. Your suggestions are appreciated.

Hey Bruce, I had no idea that a battery could have a defective internal connection.
Good to know.

-Gavin

[Scot Minesinger]

Gavin,

It sure is nice to solve a problem like this for under $0.50.  My Father in law always used to say "it is something simple", words to live by for me.

Enjoy your Cadillac.