This is an Odd one.....

[89FerrariShelby]

So I parked my car saturday (power steering disappeared, though upon inspection the pump is dry, so i'm guessing that's it...though its not whining...but oh well).

Walked out Wednesday to this....





HUH????? what could this possibly be? Noise appears to be coming from the alternator...

[RoadWarrior222]

There's a rectifier in teh alt that can die, leaving coils shorted, "normally" when this fails the car either seems dead when battery volts are applied and won't turn on a fresh batt. or it drains the batt over night... but clock the alt in the right position and it doesn't do it. What I suspect might be happening here, is that that has happened but that a brush on the commutator is only a fraction of a milimeter away from the shorted pad and it's arcing in pulses.

That's my theory anyway... stops if you move the alt?

[89FerrariShelby]

Well...i barely understood your paragraph...but despite my stupidity i went out to reconnect the battery and test if it would stop moving the alternator.

after reconnecting the battery it made the noise for a split second and then stopped.

so i'm guessing i need a new alternator? (sucks because this one is only a year old =(.....)

[RoadWarrior222]

"Sounds" like it... badoom tish

Or you can get that one rebuilt. Guy on here used to do it. Lugert.

Don't think it's too hard to replace the bit that has likely gone south, but there might be other spark/heat damage now, and something else could be out of spec too, because they don't do it that way very often. But anyway, can't direct you in that because I haven't done it myself.

[89FerrariShelby]

yeah....i got this alternator from lugert 2 years ago i think =(

oh well, just another reason to put her down for the year....thanks for the help!

[cordes]

It almost sounds like your horn is stuck on. Pull the horn relay and see if it goes away. Of course this assumes that you have a horn.

[black86glhs]

I was thinking the same thing, sounds like your horn and not the alt.

[trbowgn]

That has to be a horn!

[RoadWarrior222]

yet, the essential internal parts of a bleeper or buzzer, being a coil and a sprung contact, are present in an alt, they are just not normally wired up that way. (Or have the contacts set just so, the gap is kinda finicky).... but it will be hard to prove that, as soon as the shaft moves a fraction of a degree it will probably stop.

[89FerrariShelby]

SON OF A.... i think you guys might be right...ever since i switched to the shelby wheel it has gotten stuck a couple of times....

though how it triggered on when the car wasn't touched for 3 days is a good question...

i guess maybe i'll hook it up and drive it...see what happens...

the axle feels on its way out...so i'm already driving a car about to die...if the alternator kicks that's nothing lol...



edit...

hooked up the car and held the horn, sounds identical to me. RW222 i certainly appreciate the intelligent input, and it may very well be that...but if my alternator is shot it will just kill the car, and its a ticking time bomb anyways lol...so i guess i'll give it a shot....should it end up being the alternator i'm guessing i'll hear that noise again before too long, and i'll know what to do.

thanks for the input all! For some reason i thought my horn sounded different than that...it's really annoying!!!

[cordes]

That's how they always sound when they stick on like that. I agree that the sound a little different when they're normal.

[RoadWarrior222]

I was relying heavily on your assertion that it was coming from near the alt. Ooops I had one fart at me once, which was what gave me the idea they can do that.

Horns change pitch a bit when they have a bad connection and the horn button/clockspring deally has been known to be an issue methinks... they get a bit e-ee-ee when they have a bad ground too, rather than a fuller throated baaaarp.

Honestly, I doubt you'd hear the noise again even if it was the alt, it would be too sensitive to exact position of one of the brushes and one of the contact pads... what would happen next time is that it might seem completely dead 5 mins after turning it off, because the alt is a dead short, but manually turning the alt will let you start teh car, or it lands on that coil when you park for the day or several hours and actually flattens the battery. Way to check if the alt is acting up is to start the car, and measure voltage across the battery terminals with it running. If it's over 16V and particularly if it's jumping around over 16V then there's a rectifier fried, it's running on 2 out of 3 coils because the other is messed up, and whacking the voltage too high on that one. So if you see also your ----pit gauge hanging rather too far to the right and quivering, then that's a likely sign also. It might not go as far as teh 18V red zone, but anything much away from the middle on that gauge should be investigated.

[89FerrariShelby]

haha, that was your first mistake!!!

though in my defense it was a really annoying sound and i just wanted it off....

and the horn is right in front of the alternator lol