An alternator swap story

[Fat Daddy]

Truth of the matter is, I installed an internally regulated alternator off of an 83' l28et onto my 75'280 with no idea I now had two voltage regulators in the system...until, I fired up the car and the amp meter went haywire. This led me to research the following links:

 

http://www.zcarcreations.com/howto/voltreg.htm

 

I matched the yellow and white/blue stripe as instructed as the voltage regulator harness matched the info provided, but after realizing the system wasn't charging, I searched further:

 

http://forums.hybridz.org/topic/108455-75-280z-alternator-upgrade-to-zx/

 

http://atlanticz.ca/zclub/techtips/alternatorswap/index.html

 

All three agree that the white/red and the white/black are joined. Two out of three state the yellow and white wire should in fact be joined. So I did. Still not producing 14.4 volts. To make matters worse, my digital meter was lying to me saying it was overcharging, until the battery died minutes later. After installing a new 9 volt, it actually showed 10.5v proving it wasn't charging at all. Even after giving some rpm still no change.

 

Neither combination seem to yeild a positive result which leads me to believe that either I've damaged the internal regulator or it didn't work to begin with...I'm leaning towards the latter.

 

Times are tough in Alberta right now, blew my budget on a pallnet fuel rail and arp head studs for the l28et. I'd like to use this alternator for the time being until i can afford a larger amp version. Can I solder the original voltage regulator back in the system, or any other low budget option would be greatly appreciated.

 

Thanks in advance,

 

Jason

[NewZed]

Give a better description of what you have connected to what.

 

The internally regulated alternators are pretty simple, they just need battery power to the :"L" wire, usually supplied by the charge "L"amp, and the S wire needs to be connected to the battery and/or other loads to sense voltage.  No L and the alternator won't charge, no S and it won't regulate.

 

There are other issues to deal with related to the car wiring, but that's all that the alternator needs.

 

The atlanticz diagram works well.  You might be looking at too many things.  The atlanticz doesn't have white/red and white/black joined.  Try it, then use a meter or test light to verify power at the alternator plug.

[Fat Daddy]

I have it wired exactly as you have it shown. I should have supplied that pic in my post, as it was my reference, unfortunately it's still not giving me 14.2V. Just wondered if I damaged it when I wired it wrong?

[NewZed]

Sometimes it's best to stop thinking/guessing and just take a measurement, so you know something.  Measure voltage at the alternator T plug with the key on.  S and L terminals at the wire harness ends.  No voltage, no function.

[Fat Daddy]

Here's a pic of the original mod. Also, I forgot to mention that I've noticed some kind of condenser attached to the alternator on the 83' as shown in the pic, mine came without. There is one attached near the external regulator however. Just wondering if it's an issue?

[Fat Daddy]

Condenser shown in the lower left,any 75' owners run into this?

[NewZed]

That's the lower right.  Condensers are typically only problems if they short to ground.  Meter it.

[Fat Daddy]

My mistake, lower right. Turns out the battery in my voltage meter was dying and started climbing when testing whether the alternator was charging or not. Eventually it died, one problem solved.

 

After tracing the two wires in the T plug on my alternator by testing for continuity (which I had never done before, and hadn't realized my meter even offered that function). After reviewing http://forums.hybrid...-upgrade-to-zx/ again it put things in perspective, by determining which needs keyed 12v and which requires constant 12v. I have a new appreciation for my meter and not relying on colour coding.