78 alternator works battery not charging

[archiethe3rd]

I have had my 78 for 2 months. When I bought it I put in a new battery and it started right up and continued to start after sitting for days while I did brake work and it was still winter so not driving weather. I got it home and garaged but started to notice after I would drive it around, shut it off and try to restart, it wouldn't always start. Also, the speedo cable broke (unrelated?). It jump starts great and pop starts but will not start on its own now. I recharged the battery and it started once but then would not start again. The alternator is putting out 14 and I have clean terminals and have cleaned up the neg. ground to the body. Any ideas? Someone said maybe the ignition coil. Any thoughts on that? I haven't checked what it is putting out. Thanks in advance.

archiethe3rd

[So Cal Mark]

you don't mention whether the starter operates or not. Where are you measuring 14v?

[archiethe3rd]

The starter turns the engine very weakly now, but early on it maybe felt like the ignition switch. The engine would turn but it seemed if I let off the ignition at the right time it would fire. One night after starting on its own, driving it, shutting it down, pop starting it, driving home, shutting it down, the engine would turn but it wouldn't start until I let it sit for 30 min, then it started just fine.

The 14v reading was taken off of the back of the alternator, not sure of the grounding point, my neighbor was helping.

[So Cal Mark]

check the voltage at the starter to determine if you have a voltage drop or a bad starter

[archiethe3rd]

Thanks Mark! I apologize for the bonehead questions. But one more, what should the starter be reading? I will check it next.

[mgbgtn]

Sounds like you should take the battery in and get a load test done on it. If the car runs ok once started, the alt is probably ok.

[azruss]

The large wire to the top lug on the starter solenoid is directly from the battery. It would be worthwhile to remove all the wires from both starter solenoid lugs and clean them. same is true of the battery terminals, the battery ground to the chassis and the big ground on the motor (starter bolt to chassis). Once that is done, you can concetrate on the battery and the starter.