I recently rebuilt my 2.8L in an attempt to help it pass local emission standards. Just before the rebuild I replaced the alternator with one from AutoZone. Seemed to work fine, but I didn't drive it a lot after the replacement. Maybe 35 more miles. I am now tuning everything from after the rebuild. At about 110 miles on the new motor the alternator completely failed, and I got a warranty replacement from AutoZone, which I installed last night. This morning I drive into work and when I get here instead of a nice 16 on the volt meter in the car I am at 14. I will check again at lunch or something, when the car cools down, but has anyone else had this with burning through alternators?
My previous 86 GT didn't ever have an alternator issue, and always got great power.
Maybe part of the issue is that I don't know the gauge. 13 Volts is straight up and down. At the far left, beyond the, red is 8. The far right, beyond the red, is 18. There is a line just before the red on the right and that is where it normally rides (in my 86 GT and this morning in my 87 GT). Am I way off here?
The stock fiero volt gauge is know for its inaccuracy. The only thing I use my stock volt gauge is for is a reference. You should check the actual voltage with a good multi-meter. The voltage at idle with no electrical accessories running should be between 14.1-14.4 Have you had your battery load tested? If your battery is no good that will kill a alternator quick. The alternator is not designed to be the sole source of power for the car. Its only meant to top off the battery and keep it charged.
Yep, I definitely don't have that heat shield. I would have remembered it on the old alternator too. I bet the guy that sold it to me just didn't have it. Having never replaced the alternator in the 86 GT I had I had never seen it (or paid attention to it). Now, the better question, where can I get one of these?
Just did an inventory check at local wreckers. Not seeing anything. Let me ask you this, it seems like the only difference for the 88 motor is that GM moved the heat shield from the alternator to the manifold itself. I can find that part number and could order that heat shield. Any reason that wouldn't work?
Info received. Will send this out on Saturday with some other things I have going out. Don't know shipping costs but don't worry about it, I like to help other fiero owners whenever I can.... and lately I havent been much help just full of questions. I'll get you the tracking number this weekend. Take care and stop burning alternators up, we have enough other quirks with our cars :P
Anytime. I've had people show me the same kindness here in the past while I had my last Fiero and was still in High School 12 years ago. Although I dont assume thats your situation, lol... I am glad to help.
Edit to add... did you receive my texts?
[This message has been edited by EvilSqueezles (edited 08-01-2013).]
Alternator output should be in the 13 to 14 volt range depending on temperature. Get a voltmeter that plugs into the cigarette lighter socket, it is usually accurate enough, and better than the Fiero voltmeter. With the engine not running the voltage will be 12 volts +/- a volt depending on how long it has sat.
Also make sure the fan in the trunk is working. It comes on whenever the rad fan comes on and its purpose is to supply a constant stream of air for cooling purposes of the alt. Mine used to do the same thing with everything working in order. My solution was to replace it with a different design with a bunch of amps, 220 to be exact! I don't need that much but that alt has also other upgrades that for what I use my car for it is just perfect.