Boiling Battery

[ChromiumAge]

Today while driving around, my batter started boiling.... I'm lead to believe this is the alternator overcharging. Also, it could be a bad voltage regulator. What's the best way to go about fixing this? Any advice is greatly appreciated.

[rvercoe218]

Test the alternator by touching the positive multi-meter probe to the positive terminal on your battery and likewise the negative probe to the negative terminal on your battery. If the alternator is working, your multi-meter should read somewhere in the vicinity of 14 volts (typically 13.8v-14.2v). If it is reading excessively higher than 14 volts (greater than 15 volts) it is most likely that the voltage regulator is faulty or going bad.

[CollinsCougar]

A couple weeks ago, my battery boiled over, but that was because I had filled it too full and when current started to move it had no where for the water (now acid) to boil...so it boiled over a little bit...

[ChromiumAge]

Where can I find the voltage regulator on a 67?

[rvercoe218]

I am not 100% sure but I believe it's either mounted beside the radiator support or on the drivers side inner fender beside the solenoid. It looks like this.... or close to it... http://www.drivewire.com/includes/se...Qgd2FycmFudHku

[ChromiumAge]

Thanks! As a precaution, should I change out the battery too?

[rvercoe218]

If it were me I would charge the battery fully and load test it If you don't own a battery tester, take it to a parts store and have it load tested, It will rule out a shorted cell or weak battery.

[ChromiumAge]

Do you think the voltage regulator they sell at Autozone is solid state or mechanical?

[rvercoe218]

Call them and ask....

[Bad69cat]

Most likely solid state now - and they are known to be problematic if they are made in China....try to get a USA made one. These guyscan rebuild it or sell you a good one, or tell you how to convert it to a 1G type using your existing alt....http://www.qualitypowerauto.com/pages/AboutUs.php

[ChromiumAge]

Okay, I changed out the voltage regulator and the battery. The old regulator was clearing 15 volts when I put the multimeter on it. The new one is giving me readings around 14.6 volts. Is this within tolerated levels, or am I going to have to dive it around and see if my new batter boils?

[rvercoe218]

Did you throughly clean the battery terminals before installing thr new battery... both on the battery and cable ends? I would put a charger on 2amps and slow charge the new battery first then test it. 14.6v the max I would like to see going to the battery. Check it with the vehicle running no accessories on then with lights and heater.... then let us know the readings.

[ChromiumAge]

I drove my Cougar around a good bit today, and after I finished, I tested the battery. It's holding steady at about 12.7 volts (car not running), so I don't think it's over charging any more. I think the new regulator was what I needed. Also, I opened up the old regulator and saw one of the wires was burnt up, so it's really no surprise it needed a new one. Thanks for all the great advice guys!

[Bad69cat]

Keep an eye on it for awhile but it sounds like you got it fixed.