Hi folks

We have a 70 Cutlass supreme that were having some electrical problems with.

First off, replaced the battery last year and found it wouldn't hold charge this year. Tested it and low and behold it was toast. Dead cell. Replaced with new and improved battery and everything seemed to be working fine. No drain over night, no problems with starting etc.

A week later I go out for a run. Starts up great. Stop to get gas. Battery is dead. Jump it and drive home. Shut it off and it starts mo problem again. Starts up everything the next couple days. Take it out for a drive (cruise around town for half hour or so.). Go home for 10. Go to start and battery is dead again.

Also most of the dash lights are out. No heat. And issues with getting the top down and up. I replaced the switch and circuit breaker. Lubed up all the joints in the top frame. Pump us full and lines are good. Wondering if maybe it's connected to the battery troubles? That or the motor is getting bad and working too hard this tripping the breaker. (starts and stops then needs a minute to reset).

The big issue right now is the battery drain. Any ideas in what might be causing this?

 

If the car was running and you only shut it off long enough to get gas, the problem is not the battery. How do you know the battery is "dead"? Did you check the voltage at the battery? Did you put on the headlights to see if they work? Frankly this sounds more like an intermittent problem in a cable.

 

It's time to get out your volt meter and check voltage at the battery with the engine off and running. Off it should be around 12.6v (the .6 is very important), running it should be 14.2ish. Let us know what you find.

 

Start with your grounds.

 

Start with a through inspection of EVERYTHING. The battery clamps, the battery cables (both ends) the electrical bulkhead connector under the master cylinder, etc.

Its possible to have corrosion or broken wires inside the battery cable insulation. You might not be able to see the problem, but you might be able to feel the wires inside by bending and flexing the cable.

 

You have a bad connection and or a starter ready to go.
A 50+ year-old car needs all the electrical connections renewed. The cables do have a service life...and it ain't 50 years.

As noted when it won't start what's the battery voltage say?
Buy one of these: It's a load tester and a volt/charge system meter.
Don't buy the harbor junk model. Spend the $40 50-60 on a good unit.

 

Thanks for the replies.

Yes battery is dead. Checked with voltage meter. Throw booster pack on and it starts right up. Checked the alternator today and it appears the battery was getting no charge. Took the alternator out and had it checked. It's working fine. It was suggested that it could be the regulator.

Thoughts?

 

Disconnect and charge the battery for 12hrs. Then let it sit for a few hours. Retest with a load tester is preferred but a vom will do. Still at 12.6+?
While the battery is charging disconnect the alternator and VR. After the battery is fully charged and maintains a good surface charge 12.6 plug in the alternator and watch the voltage. Then plug in the VR. Either cause the static voltage to drop?

If neither finds the fault time to do a voltage drop test(google it). And a fuse pull test.

 

How and where did you check the alternator to realize it wasn't charging? Have you cleaned your battery terminals and cable ends?

 

It could be the regulator, but if that were the case, your lights would be dim. More likely is a bad wire between the alternator and the battery.