Would my lights dimming at idle be indication of a faulty alternator? Usually once the revs go up, the lights settle down, but it is pretty visible. I'm not running much of a stereo, just a little Aiwa deck and some pioneer speakers.

 

Seeing how the weather just got colder, I would check the belts to see how much slack there is before you glaze the undersides from slippage. Do this before you do the alternator bit...

 

So just check the tension on the belts? How much play should they have?

 

1/2 an inch, no more

 

Coming from someone who just went through this. Take a voltmeter and check the voltage between the negative post of the battery and the battery lead of the alternator. It should read between 14 and 15 volts. If it is not, a 79 has and adjustable regulator. It is easy to do. Hope this helps.

 

my car suffers from the same problem, its a 79. so how hard is it to change the regulator?? i didnt know it was ajustable. Id rather be told from someone with experience as opposed to frying my car

thanx in advance

James

 

Assuming it's not between 14 or 15, how do I adjust the regulator? Man, this is a lot of good help thanks.

 

First off, the regulator is held on by two screws. It has two three plugs that go to it. It is probably good though, you just need to adjust it. First, disconnect the battery. If you dont when you remove the cover you will most likely pop the fuse under the dash. (I did the first time). You will see two separate regualtors underneath. The one towards the front of the car is the one you want. It has two sets of point like objects and a lever on top. The bottom set is the points, the top is the back gap. You check them with feeler guages just like points. Point gap should be .012-.018, back gap should be .028-.059. The air gap is adjusted by the lever on top, it should be .028-.015. If you bend the little tab that the lever rides on so there is more air gap, there will be more voltage. Just do the adjustments, re-attach the battery and recheck your voltage.