The good news and the bad news

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MilTownSHO

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The good news = The whining sound that has been persistent for as long as I can remember is gone on the 98 SHO.

The bad news = Alternator is toast! 11.95 volts with the car running.

Stock alternator lasted 82,200 miles on the dot.
 

PrestonsSHO

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Alternator is fun to get out I just did mine 2 weeks ago. break loose the right outer tie rode end from the knuckle and it squeezes out... my arms were scratched up from getting that top bolt.

Hey atleast you know what it is now.... hope it goes well for ya.
 

Izzmo

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If you lower your subframe.. it's wayyyy easier.

Btw.. 11.92V isn't that bad. I would hardly consider that a bad alternator.. yet; going out though, of course.
 

PrestonsSHO

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11.92 is bad. The battery should be at 12.6v. If the alternator doesn't put out more than that it isn't charging it. The alt should be putting out at least 13 volts. More like 13.5-14.5 volts.

that is correct!!! mine was giving the same reading and after a new battery and Alternator the voltage is now 13.6v
 

Izzmo

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If it's staying at 11.95V and not dropping, I really don't see the harm considering everything in the car is rated for 12V, so just 50mV short is, and shouldn't affect too much. Can anyone disprove this?
 

SHOZ123

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Anything under 13.5V with the engine at 1500 rpm and large electrical loads on and it's time to go shopping.
 

IM Buddy8

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Yup.. just went through this with my Elantra but it happened to be the wire going to the alternator was full of water.. But if your not getting AT LEAST 13.2 at idle that's not good.. If you put high beams and blower on max and hit brakes it should stay above 13 at least at idle.. Check your wire from alternator to battery also when u take out old to buy new have the auto store make sure ure old one fails the bench test so you dont' waste money ;)
 

MilTownSHO

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Got a Ford Alternator for cost and it's getting fixed at the Ford dealer as I type this.

I figured I don't want to screw around with it if it goes out again. Seems there seems to be tons that fail shortly after install. So I let them do it for the warranty.
 

MilTownSHO

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UPDATE:

Car is now stuck at a gas station, due to guess what... a dead alternator.

Picked it up from FURD a few hours ago, this is why I wanted the warranty.

They are sending a tow truck.
 

E1 v2

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Excellent thinking ahead there with a known problem area. :)

^ ^ This ^ ^

LMAO - big fun watching Ford play the alternator game for once. Keep us posted on how many before they hit on one that works. Don't forget the 5800 + rpm test for a battery light because you got Windstar diodes.
Do the other tests first to give them a false sense of hope, then run up the rpms and watch their jaws drop if the battery light comes on @ 6000 rpms.
 

E1 v2

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huh?

An oversized pulley would be a speed reduction.
I've played the alternator game for my fair share and when I've gotten the wrong pulleys they've always been larger diameters than the SHO pulley.

I thought the battery light on at high rpms is a diode switching speed issue. There are two different kinds of diodes used depending on which alternator - i.e. SHO = higher switching rate diodes. The Windstar diodes max out their switching rate and just freeze at the higher rpms produced by the SHO motor.
 

SHOZ123

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Huh?? Am I talking to quietly?
Well yes it is a diode switch issue I guess if they are indeed different if you insist, which I doubt.

The SHO pulley slows down the alternator to the normal Windstar alternator rpm which mitigates alternator light issue. I always assumed it was the brushes lifting on the ring at higher rpm that caused the alternator light to come on. This only on rebuilds due to the fact the brush ring is seldom replaced.
 
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MilTownSHO

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Just called and now they are saying the battery is shot.

Funny how it tested fine two days ago...
 

SHOZ123

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Most people couldn't diagnose a bad battery if they tried. They don't take the time. They just hook it up to a tester and go from there. It takes a good 24 hours to prep and test a battery. Unless it is really bad then it only takes an hour or so.
 
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