I have that same problem (promotes quite a bit of staring)! :D

Radio shack diode works. But it sure sounds like you need to get the alt rebuilt.

Hey guys, I'm having an charging issue also, I'm on my 4th alternator and regulator , can someone take a pic of the diode and where it's located , thanks

Pull out your temp/oil pressure gauge. Pull on the wire that goes to the battery light, top middle. Follow wire back to the the plastic connector. Diode is in that connector.

My other question is, can welding on the chassis mess up the alternator ?

http://forums.pelicanparts.com/uploa...1391661143.jpg
I got a little creative with a 3 amp ratshack diode. I haven't tried it yet but when I hooked the 2 leads together the alternator light came right on.

What makes you say that? The chared diode? My car only has 30 k miles so the brushes should be OK. Maybe a new voltage reg would be a worthwhile safety precaution?

What makes me say that is your description of item 2 & 3 in your original post.
An alt rebuild will also include going through and/or replacing your VR.
Plus any quality rebuild guy will test it before tearing it apart and if it's all fine shouldn't cost you more than your time to pull the alt and make sure your don't have a fire hazard of wiring under your shroud.
You still haven't said the year of your car.

OK thanks. My car is an 84. I thought 2 and 3 where caused by the exciter diode. I'm surprised it charged at all from what I read. I'll look into having the alt tested

Aschen,

This is the article I always refer to: http://forums.pelicanparts.com/porsche-911-technical-forum/667753-alternator-light-doesnt-go-out-after-startup.html

I installed my new diode and the light operates as it is supposed to now it turns off the instant the motor fires. It also starts charging with out a throttle blip.

The only issue I see is the voltage hovers at 14.04 v. At idle. Does that seem a bit high to anybody?

Good job ,perseverance paid off!

Does it ever go above 14, like when you rev it up to 3-4 grand? I think the spec on the VR is right around 14. You don't want much higher than that or you will start ruining expensive electronics.

Just a follow up in case any body is searching the site in the future. I used diodes marked 3 amp epoxy rectifier diodes from radio shack. They are not marked with a specific type however. I got one of those cigarette lighter volt meters and it shows around 14v consistently while driving and about 13.5 if the headlights are on. I checked this against my modern commuter car and it was about the same. All signs point to positive for this 59 cent solution.

Thanks for the follow up

Can you be a little more specific. I'm looking on Radio Shack's website, and see quite a few 3A Rectifier Diodes. Which was it? See link: Search Result

Thanks, Shannon

I think your charge voltages are fine. Most 12v lead acid batteries charge at around 13.8. Stone cold and fully charged, a 'full' battery should read around 12.8.

Just for reference, when my regulator gave up the ghost, it was charging at around 17v and my tip-off was the smell of hydrogen sulfide gas as the battery boiled away. Didn't hurt any of my electronics, but did cause my AFR meter to read way low...as in really rich. It was the AFR that first weirded me out, then the smell, then I hooked up a volt meter to see what was going on. It happened only after shutting the car down fully warm and letting her sit for a few minutes. My guess is that it then heat soaked the regulator and cause the over charging to surface.

Ratshack part number 276-1141

Thanks mark I figured the voltage would be erratic and higher if the vr was gone

Pretty well the same story as Mark.

Happen during a Porsche coffee run and since I was following someone with a brand new muffler, I dismiss the smell as that.

Bolled the battery, but no harm to the electronic. The VR would be good for 5 minutes than put out 17 Volt as soon as it got warm. Changing a VR in a Cab is a real PITA.

Its a good reason to either installed a permanent voltmeter or a plug in the cigarette socket type