Charging problem

[Anonymous]

When running the car, I'm still only getting 12 volts. I've had the alternator checked and it charges fine, runs about 14-15 volts. I'm positive the wiring is correct. I'm getting voltage from the bat wire on the alternator and I've checked the ground. Would a bad voltage regulator cause this? or should it still be putting out 14-15 volts without the regulator working

 

[Anonymous]

Do you have the original voltage regulator? About an inch and a half thick, with coils and relays in it? If so, I'd swap that out right now. Updated one from NAPA, solid state, is only about $7. I had the same problem and this fixed it straight away.

 

[Anonymous]

Thanks, yea I plan on getting one, just wanted to know if anyone had the same problem before I go up there to get one. Thanks ; )

 

[Anonymous]

Is the 12 volts at idle only? If so run the engine up to a couple thousand rpm and check voltage. Also try it with the headlights on etc. If your battery is fully charged, you might not see the 14 to 15 volts, but you should see something over 12 volts. And if you have a bad battery, somethimes you cannot get more than 12 volts out of it. Try putting the battery on a charger and see if it will hold more than 12 volts.
Doug

 

[Anonymous]

Thanks, I'll try that. Got the new voltage regulator yesterday and same thing :\

 

[CobraSix]

Have your battery tested if you've replaced the Regulator and had the alternator replaced.

You should see around 13Vs, at idle even with a full battery charge.

 

[rbohm]

8) check your wiring harness at the voltage regulator as well. i had one go bad on an old merc i had. also make sure the alternator and regulator are properly grounded.

 

[Anonymous]

I went ahead and got a new battery today and now I can get 13 volts at idle at the battery. I cant crank out anymore volts though. Should I be getting more when running at higher rpm's?

 

[Anonymous]

Typically, you will see 13.5 to 15 volts at higher rpm. When increasing the engine rpm, you usually see the voltage increase and then flatten out as the regulator kicks in and limits the voltage.

You can do a poor boy test on the charging system to see if it is running off of its own juice or the battery by disconnecting the positive battery terminal once the car is running. If it dies, then something is not right on the alternator/regulator. If it continues running then you likely have a working system.

Doug

 

[CobraSix]

Poor boy test is great.

13V at idle is good. I get around 14v at 2500 RPM, but usually anything about 12V is good.