[Jay Z]

Hello everyone, this is my very first post, from a new z car owner. Well here is a wierd problem. My 1980 280zx has a newer alternator from the previous owner. I first noticed the problem when driving down the interstate with just about everything electrical on when my car stalled. I was able to get it restarted with hardly any battery charge left. Well, the car ran well when I turned everything off. Now the tricky part. The battery will run down when the car is running unless I rev the engine to about 3500 RPMs when strangely the voltage gage jumps to about 14 volts from about 12 and stays there. When this happens I can run everything without a problem. If I do not rev the engine to get this severe voltage jump the battery will eventually die and the car will stall. This voltage jump causes the lights, the windsheild wipers, basically everything to become brighter and work the way they should. I suspect the voltage regulator (which is internal right?) but the alternator is less than a year old?? Any ideas? Besides that the car runs fantastic. Thanks in advance for any help.

James

 

[yurmohill]

some of the zxs have a blub and a gauge if it has a blub it must work. if not turn the key to the run positin and release the park with the engine not running the brack light should stay on. if not check the blub check relay (sorry i can't remember it's location).

 

[79-280-ZX]

Please read:

http://www.zcar.com/forums/read.php?f=1&i=228418&t=228418

It may help you out.

Wayne Monteath
Masham, Quebec.

 

[PA31]

Haad the exact same prob with my 83...Turns out it was the diode plate in the alternator and you'll need a new one, 200 bucks OZ...If it was the regulator you would be getting more than 14 volts...When its runing normally you will get 14.4 volts or if you turn everything on 14 V...Good luck...Ps If you decide to replace it yourself and you have power steering , the only way to get it out is to disconnect one of the hoses and hope you don't lose to much fliud then bleed the rack when your done...Matt

 

[Madeline Michele]

First thing to be aware that a fresh rebuilt is bad all to often.
Age is not something to gauge alternators with.
This could be many thing all looking at that alternator.
When you get a new one go to a long known parts store that has a lifetime warrantee.
Keep the receipt and change it as needed.
Lasts a lifetime, like a Snap-On or Craftsman.
As for it being wierd, they are all that way.

Madeline Michele
Is that Hollywood Cali forn I A?
Ere is it Flarada?

 

[Jay Z]

Thanks for all you're help, I was wondering, does anyone know if you can remove the diode plate and repair it with new components? Once again, thank you for all the assistance, hopefully I still have the receipt for this puppy and bring it back under warranty.

James