Is my alternator dying?

[IIA]

My 1970 IIA has no heater fan, charge light stays on, turn signals don't work, and headlights seem a little dim. Does all this mean I have an alternator problem? Or could it be something else?

And if the alternator, is it worth trying to get it fixed or should I just junk it?

[SafeAirOne]

Put a voltmeter on the inspection sockets after the alternator comes on line. If it reads less than thirteen and a half volts, you need to investigate why your electrical system isn't receiving the necessary voltage. Maybe alternator, maybe voltage regulator (if you haven't converted to an integrated alternator yet, that is), maybe a broken wire terminal or bad connection, maybe the alternator isn't being excited (depending on which alternator you have installed).

Either way, don't drive too far from home--after a while there won't be enough voltage available for the primary circuit of the coil to generate enough electricity in the secondary coil to spark across the gap of the spark plugs.

[IIA]

Put a voltmeter on the inspection sockets

So I have to replace the missing inspection socket first? Is there any other place I can test the voltage? Also, how do I tell if I still have a voltage regulator?

[SafeAirOne]

So I have to replace the missing inspection socket first? Is there any other place I can test the voltage? Also, how do I tell if I still have a voltage regulator?

You can just test it at the battery.

Is your voltage regulator internal to the alternator or external?

As for the voltage regulator...I don't know if they were still using external voltage regulators in 1970 or integrated ones, but if it's an EXTERNAL regulator, you could always test the alternator's output by putting your voltmeter's red lead on the terminal where the fat wire comes into the regulator from the alternator and the black lead on a good grounding point and see what sort of voltage reading you get with the alternator on line.

If you are getting more than 13 volts there, but not-so-sufficient voltage at the battery, then the regulator is suspect. If you have an INTERNALLY-regulated alternator, there are a different set of steps you could use to see where the problem is, but we'll worry about that if you say that you have an internally-regulated alternator.

[IIA]

I think I'm making some progress. I'm pretty sure I have an external regulator, because there's a black box labeled "voltage regulator." I'm assuming the prior owner didn't have an evil sense of humor. Also, I suspect that the reason my alternator isn't working properly is that I don't have one. After some research, I think I have a generator instead.

So I tested the battery and got 13.2 volts. But after the engine had been running for a while it was down to 12.75v. The charge light wasn't on (for the first time in days) but I'm not sure that matters. I tested the voltage regulator as you suggested and got about 12.9v

Does that mean anything useful?

[SafeAirOne]

Well, you'd have to figure out what you have, alternator or generator, to start.

[Cutter]

Make sure your belt is tight. I had some wonkiness going on a few years ago and the belt was slipping. It was fine at idle so when I was testing things everything was great, but would slip when driving leading to the same symptoms you are having.

[IIA]

Well, you'd have to figure out what you have, alternator or generator, to start.

Generator.

[SafeAirOne]

Hmm. I'm afraid I won't be much help in the generator department. I have no idea what's normal with those.

At one time, somebody (Les, possibly) posted a manufacturer's document detailing theory of operation, testing, troubleshooting and repair of the external voltage regulators used in the series rovers. I come across it every now and then but of course I can't find it now that I'm actually looking for it...

[NC_Mule]

I just went through all this before switching to a alternator. The Green bible has a simple test to check for volts coming out of the generator. Then two more tests one to check the voltage side of the regulator and one to check the amp side of the regulator. One of those tests requires special equipment can't remember which one right now. It has a funny comment like "take to mechanic" if you want to test this......think it's the amp side of the regulator.

Another thing to check are the contacts at the voltage regulator, pop the cap off to see them. Make sure they are in good shape.

pb

[LaneRover]

So I guess the alternator is not dying though the jury is still out on the generator . . .