280zx internally regulated alternator

[Ranman72]

so I have a 280zx alternator conversion on my 68 510 and something weird happened the other day

I was passing a car spinning about 4700 rpm when the alternator light came on I checked the gauges and the temp was up also my temp gauge is an auto meter electric gauge so we pulled over thinking I lost a belt. belt looked good and tight. I proceeded to drive to the nearest town thinking the belt was slipping got a belt and still had the same problem the temp seemed to stay down if I kept it about 2000 rpm or less so we babied it home and got to work

 

I found some odd color splatter in the engine bay turned out to be battery acid so I checked the charging system and my 400 mile old Napa Gold alternator was putting out 15 volts at idle and 19.5 volts at 4000 rpm and climbing (this is not good ) I checked all the wiring and everything looked good so I returned the alternator for another one and let them know what damage it had done to the engine bay paint which they apologized for

 

so new alternator installed charging at 15 volts temp is good everything is good so

 

what I figured out was the alternator was putting out such high voltage that it was making the temp read hot when it wasn't hot at all so I learned something new to much voltage can make your electric gauges read high and the alternator light will come on if the car is not charging or if the car is charging to much

[banzai510(hainz)]

the regulator went bad in it . Otherwise they alwasy put out a higher but unregulated voltage.

 

key is run a volt meter so you can catch this right away and alway monitor it.

 

if one has good coltage at idle then puts lights and heater on and it doents lower the volatge soemthing is starting to happen, Gareentee it

[Ranman72]

good to know about the lights 

I think I am going to run a volt gauge just because the problems I have had 

I thought if the charge light was on the alternator wasn't charging  which I found out is not the case

[datzenmike]

The charge light is wired to the battery on one side and the charge on the other. As long as you have about 12-15 volts on each side the bulb can't light. If the alternator quits, power can flow from battery into the alt. and it lights. If alt over charges power flows from alt into battery and it lights.

[banzai510(hainz)]

this was my favorite until it broke

I think they only worth 10$ myself but I like it.

http://www.equus.com/Product/3721/Battery-Monitor

 

plug in cig lighter

[Ranman72]

thanks for the heads up banzia my friend has a home made plug in one its an easy way to check the voltage

 

thanks Mike for the explanation of how the dummy light works I thought they only came on when not charging

but now from experiance I can tell you it is super bright when over charging

[banzai510(hainz)]

I run a diode volt meter light the cig light.

I have contance proplem with my alt bolts comming loose  from the engine. threads wore out.

 

I have run in the huge water puddles and bolts falling out loosening the alt belt and I can see when Im not charging right away.

AND NEVER HAS THE IDIOT LIGHT EVER COME ON. By the time it does its mostly already to late to make it home

 

 

I persoanlly light the diode type as you can see the instantly when soemthing happens

[Just Joel]

When running accessories such as headlights or heater fan and blinkers at the same time, I can see the alt light (280zx 60amp btw) faintly pulsing with the blinkers (at idle). while this is happening, I can see that the voltage at idle with the lights or heater on is around 12.5 v and the blinker will cause it to drop to about 12 v-11.5 v (momentarily while blinking) so it seems my light comes on pretty early.