iM GETTING 18 VOLTS AT THE BAT WITH THE CAR RUNNING AND 14.6 AT THE BAT WHEN ITS NOT RUNNING. IM THINKING BAD VOLTAGE REGULATOR,WHAT DO YOU GUYS THINK? THANKS..STEVE

 

Do not run it any longer!
Battery will overheat, possibly short interally and pop.
Alternator and wiring can overheat from excell current and be damaged as well.

Yes, bad regulator.

 

Thanks for the reply! Steve

 

YES, YOUR REGULATOR'S SHOT! TURN IT OFF, MAN! ABORT! ABORT!

BUT YOU DON'T HAVE TO YELL ABOUT IT!

- Eric

also, sometimes you can get a few miles out of one that's doing this (like when you're stuck somewhere) by striking the case sharply with a big screwdriver or wrench while it's running.

 

Lol I was using a computer at work

 

Yeah - I tend to do better on my Mac at home - work computer always seems unnatural.

 

Maybe your meter is a little off. Over 14 volt while not running seems a little high to me as well.

 

If the battery was overcharged, it would be way over 12.7V after the engine was recently shut down.
Turn on the headlights and check again - it should drop back to its natural 12.7V after a short time.

 

What Rob said - you can have a high surface charge that dissipates as soon as you put a load on it.

- Eric

 

Its at 12v now, I did put the meter on it as soon as I shut it down. Got a new volt reg coming from napa. Thanks guys.

 

go for an internal regulator...unless you're a purist or this is a show car.

 

Yeah, that's the best fix overall, but then he's got to change the alternator and mess with the wiring.

Just changing the regulator will get him back on the road with two or three screws and a plug to push in.
He doen't even need to get his mitts dirty.

- Eric

 

But how is this?
An external one works just as well, especially if it is an electronic variety...

 

If you are getting 14.6 volts with the engine NOT running, the problem is likely your voltmeter. The battery is designed for 12.8 or so, and the alternator puts out 13.8. Double check your voltmeter accuracy on another car that's known to be good before spending money on replacing parts.

 

check all ground connections. also a bad battery or a battery low on electrolite can cause overcharging. If it has been overcharging for some time the battery may be low on electrolite now. Good idea to check it too.

 

Once you get this all sorted out, I'd still make the switch to an internal regulator...it is the best fix overall as Eric mentioned.The wiring is super simple and it's one less hassle once the job is done..

 

What is an internal regulator? Where do I get one? How do I install it? Thanks!

 

An internal reg is one that is mounted inside the alternator instead of on the firewall. It is a small electronic device. Many people want them as it cleans up some some of the wiring in the engine bay.
Modern high current (over 75A) alternators usually use internal regs and people need higher current when they run electric fans or super high power radios.

The disadvantage on an internal regulator is that it is a lot harder to change being in the alternator. Many of the newer alts cannot even be disassembled easily. When the internal reg fails, you are supposed to replce the whole alt for a lot of time and $.

If you can get an electronic one that mounts on the firewall, I would keep it external for simple's sake. Of course this only applies if the current alt output is adequate for your power needs. If the car is all stock, then it is adequate.

 

1. What on Earth is a "a tm-701l 7 inch screen," and how does it relate to Oldsmobiles?

2. Why would you want to play video games in an old car? Wouldn't rather be enjoying the ride?

3. A running car's alternator produces somewhere between about 13.7 and 14.4 volts (specifications vary). A quiescent charged "12 volt" lead-acid battery is somewhere around 12.5 volts. If you want to have a 12.00 volt DC power source, you will need to get or construct a high-accuracy electronic voltage regulator, of the sort that is usually INSIDE of audio and computer equipment. In order to buy or build a regulator, you need to know how much power your anticipated load will draw. A quick check, assuming a load of at least 10 watts, shows DC to DC regulators in the appropriate range here, from about $25 to $55. You would have to research the voltage tolerances of the regulators and of your proposed equipment.

- Eric
(should I start signing my name, "Norm?")

 

[quote=Lady72nRob71;280806]
The disadvantage on an internal regulator is that..... When the internal reg fails, you are supposed to replce the whole alt for a lot of time and $.
quote]

Not true. The best external voltage regulator offered by O'Reilly Auto Parts (has lifetime warranty) costs more than the internally regulated alternator (also has a lifetime warranty), which only takes 20 minutes to install. So $ and time are no worry.

 

i bought the electronic one from autozone its half the size in thickness compared to the original but seemed to work fine. maybe you could charge a hybrid with all that extra juice!

 

That would be like hooking Chernobyl up to the Energizer bunny...