Cranking Problems

[dickeymoore]

I have a 1986 Monte Carlo SS with a SBC 406,It has new 100 amp one wire alternator,1000 CCA Optima battery and Mini starter if I let the car sit for a day or so with the battery hooked it will not start like the battery is dead,its like something is draing the battery when it sits but when its running I'm getting like 13 volts on my battery guage,so I have to unhook battery when it sits any HELP?THANKS

 

[shaggydjlg]

hook a volt meter between the pos cable and pos bat terminal and start pulling fuses one at a time when the volts jump back up it will give you an idea on where to look for problem.You might even want to look at the wireing to make sure its not touching headers or anything hot and melted the caseing.

 

[LS6 Tommy]

You're only getting 13 VDC at idle? Something's wrong. A good battery should read 12.5 VDC minimum static (with the car turned off). Idle should be at least 14 VDC with all the accessories off.

Tommy

 

[dickeymoore]

Should the car be running or not when hooking up the volt meter?THANKS

 

[shaggydjlg]

car should not be running when checking fuses

 

[dickeymoore]

Will the wires on a Voltmeter reach inside the car while I'm pulling fuses?THANKS

 

[shaggydjlg]

no there only about 6-8 inches long besides you wouldnt want them long enough to reach inside car.The longer the wire the less resistance you will have and that will give you a false reading.you might want to get a friend to help you look at the gauge while you pull fuses

 

[dickeymoore]

Hooked volt meter getting 11.8 with car not running,pull fuses one by one no change on meter any HELP PLEASE

 

[fastheavychevy]

Hooked volt meter getting 11.8 with car not running,pull fuses one by one no change on meter any HELP PLEASE

Sorry about your problem I know how you feel my advice from experience on working on cars and selling parts is if the alternator has a bad diode inside it will keep the alternator energized the alternator keeps drawing power from the battery and it will kill your battery probably in a few hours or sometimes over night if its a good battery you can take it to autozone and run a check on it or try disconecting the main wire from the back of the alternator is it doesnt discharge the bat. then thats could be your problem cuz thats the wire thats sends the charge back to the battery also check the little brown wire fron the alt. plug with a volt meter it should not have voltage with the key off and volts with key on let me know what happens

 

[dickeymoore]

Battery is a NEW Interstate and the alternator is a 1 wire type.