DartThis74
Well-Known Member
I was driving my ‘74 dart yesterday and realized the needle isn’t reading in the middle. What is this needle position on the gauge telling me? What are the other marks supposed to mean as well?
The Way your gage reads, it is over charging.
How long was it running when you took the pic. Should go to center after 5 or so min's, on good battery.
Or you might have high resistance some where in the circuit.
It could be lots of common things, in the wiring, specially in the bulk head connections.
Is the batt good, how old is it. ??
Check all your connections, use dielectric grease on batt connections
Dave
That means charging is increasing with rpm.Currently... I pretty much have been driving the car about 1-2 times a month on a weekend. When I first start the car it sits in the middle roughly but if I push the gas it bounces all the way to the right until I let of the accelerator.
Sounds like the battery could use a good charge on a charger.After 15 minutes maybe it will finally settled and stay fixed.
it will cook off the water (acid), or occassionally worse.If it is truly overcharging that would just make the battery wear out faster I assume?
Yes. That or load tester.To really know the state of the battery, you'd need a hydrometer if you can check the specific gravity of the cells, that is, not a sealed battery.
The VERY FIRST thing you need to do is get the car running and clip a voltmeter direct to the battery. Increase RPM to simulate cruising speed and see what the meter reads. If it's very much above 14, or an absolute limit of "above 15.5" (and that is somewhat high) then the regulator is not properly controlling the voltage.
If the voltage is 14 or lower the battery is "down" (somewhat discharged) or bad. IE defective battery.
If you drive your car occasionally and a few weeks between drives, put a trickle charger on it one day a week or buy a battery maintainer. It looks like it's charging about 20 amps. Pretty normal for a battery that is low on charge. Yes you could test it or have it tested but it needs to be fully charged to get an accurate test.
The 'alternator' gage is an ammeter showing current to or from the battery.
Normally it sits at zero after the battery has recharged.
That means charging is increasing with rpm.
Possible reasons for this include
1. Voltage regulator not working.
2. Battery low combined with alternator that's producing at reduced capability. An alternator producing normally should be charging the battery at fast idle.
Sounds like the battery could use a good charge on a charger.
it will cook off the water (acid), or occassionally worse.
If the regulator isn't working, then the whole system is running at higher than 15 Volts whenever the engine rpms are increased. Every electric device given power at higher voltage will suck more current, so lots of things can get damaged.
In my opinion, the first check would be to take a handhand multimeter and measure voltage at the battery, engine running at idle rpm (650?) and then at 1250 rpm, or fast idle (1600ish). If it goes up a little, but stays under 15 V, increase rpms more just be sure.
If that checks out ok, then check voltage at idle and 1250 or 1600 at the at the alternator output (if accessible - some are covered in a boot), and at the nearest junction to the voltage regulator sense wire (back probe at ballast resistor or the blue wire conencted to the alternator).
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You're lucky. Full charging like that can trash a amp meter and Then no chargo' in battery-o.I drained my battery, 3 years old, till it would not start the car. Jumpered and all was fine but ammeter was in the same position. I drove it for 45 minutes and it was still there.
Had battery tested came back good but low on charge put it on barttery charger all night. Next day charge indicator in the center to just right of center.
Shocked me
No alternator likes being maxed out for long periods of time.Mopar charging systems aren't designed for and don't like full alternator output.
Does he have a bunch of thing pulling power at the battery????
That would show an overcharge condition when in fact it was just providing energy to those accessories.
Very good point