68 Battery Drain

Space Cowboy · 10-09-03, 02:51 PM

I purchased a 1968 427 (but now has a small block 350) last week and I'm being driven nuts with an electrical problem. When the battery is fully charged, the engine will crank over without any problem. After the car and ran or sat over night, it has a hard time cranking do to a voltage drop. So far, I've replaced the altinator, voltage regulator, and horm relay. I just checked the battery this morning and had a 1 volt drop. Another side note... the engine has a newer Delco electronic distributor on it.

Anyone have any ideas what the problem could be?

JrdnsEdu · 10-09-03, 02:54 PM

Is it a brand new battery? Maybe it just wont hold a charge. I know Checkers and Autozone will do a free battery test to see if the battery is still good or not. Maybe cruise the battery over there if you have one near you to rule out the battery.
-Eric

Space Cowboy · 10-09-03, 04:13 PM

I'm actually on a second battery which is new. It maintains a good charge unless its connected.

Pertaining to the "Bulb Fuse". I should be able to do essentially the same thing with a amp meter on a continuity setting, yes? If there is a short, I should get a reading.

Thanks

Yoda · 10-09-03, 04:25 PM

Quote:

Originally posted by dnewton
..... . . . ...Pertaining to the "Bulb Fuse". I should be able to do essentially the same thing with a amp meter on a continuity setting, yes? If there is a short, I should get a reading.

Thanks

Don't do that dn...

Place the meter on DC Volts.. or series in the ampmeter.. setting it on continuity will fry the meter

you want to see voltage on one side to ground and not the other, your not checking for ohms

Bud

Space Cowboy · 10-09-03, 04:42 PM

ahhh... you are correct. Where is my mind today. Thanks for the warning. It's a fairly expensive meter. Is one side of the fuse connection a common ground?

ChuckG · 10-09-03, 06:59 PM

Check your wiper service switch...the one with the big knob down where the vacuum override buttons are located.

If you leave this "ON", it will cause battery drain. Chuck

WETVET · 10-09-03, 07:10 PM

You might want to try putting a battery disconnect switch on, they are not expensive. Most auto parts carry them. Then you can save the fully charged battery.
Good Luck

Space Cowboy · 10-09-03, 08:08 PM

Man... my first gripe! They were definitely not thinking where they put the fuse panel... sheesh, what a circus act I performed!

Here's the meter volt readings with the fuses out:

Wiper = 3.41
Gauges = .06
Signals = .07
Radio = 11.66
Stop Light = .46
Tail Light = .18
Clock = 11.01
Heater = .98

Which ones are valid voltage readings and which ones should I be concerned with? Thank for the help... I know nothing about electrical systems.

Yoda · 10-10-03, 08:40 AM

Without looking at a schematic or at least a wiring diagram I'd be shooting in the dark.. I can say and I echo what c5d is hinting at...

There are circuits that will have voltage with the key off e.g. "Clock and Cigarette Lighter" come to mind, the Radio may or may not depending upon model and electronics of the Radio.

As a note to possible help you with understanding a bit more about this type of testing.. the purpose of pulling the fuse then testing from one side of the fuse clip to grd.. if it is a "Hot" circuit you should read voltage from the fuse clip to ground, if it is a Ignition Key controlled Hot Leg then the key will need to be in the on/run or acc. mode to read voltage to grd. Ideally you would read voltage (11+ 2 volts) from the battery side of the fuse clip and 0 volts from the load side of the fuse clip with the fuse pulled.

I wish you luck in chasing these gremlins down, sometimes they seem to be magic. I've found bulb sockets to be a source of drain, they get old and corrode and form a path to grd and slowly drain the battery. Other places I've found grounds are from the vanity mirror switch, door switch to the hood light wiring.

It also will help if you WRITE DOWN the tests you conduct and voltage and notes. At some point you may find yourself going in circles without documenting your progress

Good Luck and may the force be with you

Bud

Space Cowboy · 10-10-03, 07:07 PM

Forgive my ignorance, but what is the (where is the) wiper service switch??

I know for sure I have a short. I pull the neg. lead off the post and put my meter between the two and it reading 12+ volts.

Space Cowboy · 10-10-03, 07:30 PM

Is this the overide device under the steering column?

Space Cowboy · 10-10-03, 08:06 PM

I think I may have found my problem.... could be a faulty ignition switch, but I realized that I was able to take the key out in Accessory mode. There are no markings, so I had no idea there was a position for accessories. I am able to remove the key from the ignition in that position. I dont think thats normal is it?

I will know tomorrow for sure after I take a volt reading from it sitting over night.

Thanks for everyones help. I feel pretty stupid about now!

Space Cowboy · 10-11-03, 05:25 PM

Well, I still have a 7v drain somewhere, so its back to "properly" checking the fuse panel again. More later.