"Aspire" alternator in festiva not charging

[robotrob]

ive put a fuel injected 1.5 out of a 98 festiva into my 88 121 but the alternator isn't charging

The charge light on the dash stayed on, I tried a few different ways to hook it up and I think I blew the diode in the instrument cluster because it's not coming on at all now so I rewired my own charge lamp/excitor with a spare T5 bulb I had.. Still not charging

So I figured it must be the voltage sense wire (maybe) it's a red wire that goes to the "head" main fuse.. Connected it to the battery and still not charging.

I've swapped the alternator and still same thing..

Any ideas? I'm getting 8.3v with the engine running

Cheers,
Rob

[robotrob]

Ok so the light is slowly pulsing, 2 or three seconds on then it goes out for half a second, battery (needs charge) 11.5 not running, 8.1 with running with lamp on jumping up to 8.8 when lamp goes out...


Bulb is 5w, I tried 2 in series and it made no difference alternator "makes a noise" when the light goes out..

Really stumped

[Advancedynamix]

After 1996 the alternators are controlled by the ECM. At least that's how it is here in the U.S.

[FestYboy]

Use the 88 alt??? Swap pulleys?

[robotrob]

The 88 B3 is small nose and the 98 B5 is big nose so crank pulleys don't swap over..

I feel kind of silly now but I've fixed it, first alternator was cactus, and by the time I swapped in the second alternator it was dark and I was tired and I'd been messing around with it for a few hours, the belt was old and glazed and I didn't tension it up enough so it started slipping every time it started charging Lol. Even now the slide bracket is at the end of its travel so I'll have to look for a shorter belt

[Advancedynamix]

You can also change the pulleys on the alternator itself. There are a couple different shaft styles though, so that may not work without making custom bushings and shims. It's worth a try though. The later alternators don't operate the same way as the early ones.

[FestYboy]

That's what I was referring to, swapping the alternator pulleys.