280zx alternator charging issue
 

i thought my battery was dead so i baught a new one and it turned out it was the alternator because when i started the car, it only read 12.3v. I replaced the alternator and the only issue im having now is I have to kick the rpms to 3500 to get the alternator to kick on and start charging after that it reads 14v+.

when i start it up it reads 12.8-13.6v but when i drive at night and forget to kick the alternator on, the lights drain out the battery, everything is fine if i rev it past 3500 rpm and let it go, the voltage will stay at 14+.
could it be the alternator belt, i haven't had the chance to replace it and sometimes it squeels even though its tight

If it squeals, it's not tight.

Where did you get your alternator from? Used? New? Reman?

it doesnt squeel always, just once in awhile
it was remanufactured from autozone

Take your car (or alternator) back to "AutoClone" and have them run a load test on it. AZ reman's aren't all that reliable.

Your new alternator is junk. Mine had a fresh alternator on it when I got it, it did the same thing.(cheap rebuilt junk)
I knew it was going to go, but didn't wanna spend the $, so I just wound it up a little and it worked for 3 yrs. That's less than 3k miles for me.Finally last year I had to breaak down and spend 20$ at the wrecking yard to get one that worked right. I've got another engine scheduled for mine, and I'd hoped to have it in before my alt went out...:) It has a better alt....something like 200amp...:)
Far as the squealing goes, that belt system works fine when eveything's up to snuff, but let the battery get low, and alternator not kick in until 3500, and a NEW well adjusted belt will squeal too.
OH, mine kicked in about 12-1400, yours is much worse off. I had an alt do this on my 70 datsun pu, and as time went by, I kept having to turn it faster to get it to kick in. I gave up on it when it took 15,750RPM to make it work.(before everybody says I can't/didn't,yes, I did turn it 16k, I had 2 su carbs, turned 7k engine, and drive ratio was 2.25)

One other thing, an AZ load test has little chance of finding it, it works fine at speed, and that's the only way they test.

Same here about the belts. Although i have the issue of the alt not staying tight. i pound those three bolts as tight as i can, and it just gets loose again. and i never hear the belt squeal, i have had elect problems in the past with it, so i always keep an eye on my gauges, with these cars. you should.

There is a little problem that could be causing that. In earlier years they had a alternator mount bracket made of welded plate, which developed myriad problems. It was replaced with a cast bracket, which my 79 has, and that put an end to most of the bracket problems. You might want to check that you do indeed have the cast bracket, they're interchangeable.

i bought one of those Adjustable custom brackets like MSA sells. but i found it somewhere else for 20$ cheaper. Part of that 2K parts spendin spree i went on. Just got to get home to install all the parts now.

i've had the same problem although with a VG alternator, they burn out fast to begin with but i got a reman and it was dead off the bat, it does have a lifetime warranty though and i did pull it and install it in my 280zx since the factory alternator wasnt able to produce the juice it used to any more.

it was a well worth swap

It won't be long at all till i have to upgrade. my next swap will be no less them 80amps

80? what cars has an alternator that makes 80 amps?

MANY cars have 80amp+ alternators... GM 1-wire alts go from 70-150amp... there's also the Maxima upgrade...

Fubar is probably doing something crazy custom though. :D

There are a few Lincoln's around with an ice melting option for the windshield that have a ~200 amp alternator, although I can't see any reasonable use for one.l

lol who knows. this new SHO motor i just got for free might find it's way to use. hell dude gave me entire car. and no, not custom on the alt, maybe a mount, but thats a givin

oooh!!! I love those SHO motors... the criss-cross intake runners look so pretty!!! :unibrow:

Yep!:) Yamaha knows how to make an intake. Sure was a crappy place to put it..:) I'd almost think about trying to make an intake like that for my v8...:)