'79 B200 overcharge overcharging

[Dennis/Ohio]

I replaced the voltage regulator and voltage at the battery is reduced but still high 14.7 volts. Temperature near regulator is 130 degrees.
Any resistance in charge circuit would cause undercharge not overcharge?
For testing I connected a wire from alternator BAT connection to battery positive post. Also a wire form Alternator case to regulator case and to battery negitive post. Voltage unchanged, still 14.7 volts.
Thanks, Dennis...

[alloro]

Yes 14.7v is on the high side, but it is not too high of a charging voltage. If it makes you a bit uncomfortable, verify your engine to body grounds to make sure that no voltage is being lost across them.

[landyacht318]

I have a solar panel and battery monitoring system installed on/in my van, which will show battery voltage and Alternator amperage with the engine running.

Whenever my batteries are in the 80% to 95% full mark, the voltage will almost always be in the 14.4 to 14.8 range at idle and climb over these numbers at higher rpms. The amps during these readings are usually on the +3 to +9 amps range, which are enough, over time, to overcharge the 2 batteries, but that amperage drops the closer they get to 100% full.

When my batteries read less than 80% full, the voltages only climb upto 14.2 under accelleration, but the amps will read 30 to 60 whatever the rpm above 1200. Idle speed amperage always will read lower unless the batteries are full.

When my Batteries read 100% on the monitor, the voltage rarely reads above 13.5( +.2 to +2.0 amps) , whether under full noon sun or at night or high rpm's. I have the settings on the solar charge controller set for very high voltages (14.8 acceptance and float). The alternator and the engine ECM overrule those voltage settings somewhat to my irritation.

So go for a long drive, or put your battery on a trickle charge overnight, and see if the alternator charging voltages drop.

It is also possible your battery is old and sulfated, causing the regulator to make the alternator try harder to bring it up to it's full original capacity, which it cant.

Thats why some will say a weak/old/sulfated battery can hurt fuel economy.

A healthy fully charged, rested battery (6 hours of no charge or load) should read above 12.65 volts and preferably 12.8. If after fully charging it and the resting voltage drops down below 12.4, it will still have enough juice to start the engine, but start saving for a new battery and keep the jumpers handy, because it's on it's last legs.

Also, starting batteries cannot handle being discharged deeply, and will almost certainly fail shortly after having to be jumped numerous times due to a undercharging or multiple deep discharge situation.

If your really worried about an overcharging situation, see if the battery is warming up, and listen for excessive gas bubbing out from the caps after shutting off the engine, or hook an HD amp meter in between the battery and alternator and get worried if that number is over 10 amps when your are sure the battery is already full.

One other thing I remember reading on this forum is how the external voltage regulators have to be grounded before rehooking up the battery and starting the vehicle, or they fail and will overcharge the battery.