Hello all,

I have a 1979 E150 van that I've been working on for about two years.
Engine rebuilt, almost every part in engine compartment is new.
Been running well, until my last road trip.

The Alternator gauge, which is usually dead center between D and C, right on the middle line, started to move to the right, towards the C.
Then, my headlights went out on the highway.
Then several little electrical glitches started happening.
Then a sulfuric odor started to happen in the engine compartment, coming from the battery.

I was advised to change my Voltage regulator, the ONE part that I hadn't replaced, I honestly never even noticed it, it's tucked in a hidden place.

So I just changed it, had battery tested, its ok.

But the ALT gauge is still moving to the right, towards the C, and further and further the higher the engine revs.

Any Ideas? I'm learning all this on the go, but can't figure out what this could be!

 

congrats on getting your ride back on the road! i'm still trying to get mine there.

so it sounds like your gauge is an ammeter meaning it is showing whether your alternator is charging the system or not and how much it is or isn't charging. C is for Charge and D is for Discharge.

*so something occurred to cause the alternator to start charging while you were driving. then you lost your headlights. what did you do to fix them? or are they back working?
*then you had some electrical glitches. ok, but what were they? are they gone?
*then you smelled stinky stuff... ie the battery.
*now the ammeter shows the alternator charging.

if you find the headlights are no good - as in they don't light up, and as you smelled battery acid, i'm going to guess the alternator was overcharging the system and raised the voltage to the point where the bulbs couldn't handle the voltage and blew out.
i would first suspect a battery problem, but you had it tested. so we will assume it is ok for now.
assuming you have an alternator on the car and a regulator separate mounted on the firewall or something, here is what i would do.
1 i would make sure i had a lit IGN lite on my dashboard when i turn the key to run w/ the motor not running.
2 i would make sure i had switched IGN +12v at the regulator I terminal. and i would also check to see that the wire going to I was not shorted to ground (do test with the key off and the regulator connector unplugged) with your meter set to OHMs, it should read more than 500. (there should be a resistor that parallels the IGN litebulb - usually it is in the 500 ohm range that way if the bulb blows, voltage is still going across the resistor to the I terminal and the charging system will continue to work correctly)
3 i would also check continuity of the two wires going to the alt from the regulator - F and S for Field and Stator - unplug both ends before testing. i would also test the same two wires and make sure they are not shorted to ground - esp the Field wire.
NOW RECONNECT EVERYTHING
4 then start the motor and check voltage. (anything above 14.7V and i would immediately turn it off) i would check all my ground leads with a multimeter - battery to frame, battery to engine, battery to body - while the engine is running. set the voltmeter to VOLTS, hold one lead on the battery post and the other at the other end of the cable and read the voltage - it should be no more than 0.02V. (if the alternator does not have a good ground then it does not know at what point to stop charging)

check this stuff out and post what you find. let's see if we can get you all happy again.

neil