This will be the 2nd time I replace it in probably less than a year. IT has a lifetime warranty so that's not an issue. Same think happened last time. My alternator would peg the neelde at full over charge. I've cheked with another gauge and sure enough 18 volts. It does it sort of intermitantly and when it does I turn on radiator fan (I have an overide switch) and a lot of other things which get it back to 14 volts. So what aside from a bad regulator in the alternator could course this?

mines charged about 16 v for last 8 years with 2 alternators. I also notice a few volt drop when the fan comes on (mines still auto) and when I use my driving lites. I havent worried about it for 100K. I would say that 18 is too much though. Maybe you have a short in your manual wiring somewhere or in the actual fan motor itself.

[This message has been edited by rogergarrison (edited 05-08-2005).]

Over charging at 18 v for long periods I beleive will ruin a battery. When it gets into one it's regulator-crazzy, it can also at times drop the voltage too low. With nothing on but the engine it should not want to stay at 18v. And a fan should cause a voltage drop to some extent. A short or overlaod should cause the voltage to drop not go above max. Something is amise here?

Not necessarily. A short can 'fool' the regulator into thinking it needs to put out more charge to compensate for a loss thru the short.

Sounds like the regulator to me, time for a new alternator. Take it in and have them test it for you.

you need to check the wiring for the alternator. If the wire that goes to the Sense terminal is bad then the alternator will over charge just like a bad regulator.

A bad ground can also do this. If the alternator case isn't getting a good ground to the block or the wiring in the engine bay is bad... You can get overcharging or even blown alternators.

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quote Originally posted by theogre: you need to check the wiring for the alternator. If the wire that goes to the Sense terminal is bad then the alternator will over charge just like a bad regulator. A bad ground can also do this. If the alternator case isn't getting a good ground to the block or the wiring in the engine bay is bad... You can get overcharging or even blown alternators.

Ogre is right on here.

Check the voltage regulator connection on the alternator!!
More then likely its dirty, causing overcharge.

Mine was a bit dirty and my charge was doing the random bounce between 12-17 volts.
Cleaned it, and its working perfect again.

I checked to make sure they the wires tight, I'll undo them and make sure they're clean too. BTW; in addition to the the case being grounded, I also have a cable onder one of the bolts to insure a good ground. With it being bit intermitant, I probably do have some corrosion on the connector. Thanks people, you can find me under the car in the morning. Aside from fixing that problem, I'll ne pulling my springs to put Itracts in. And no, I'm not going to use cheep clamp to get them off the shocks. My son-in-law wiill take them to his shop and do it the safe way. With the car going to shows to represent out manifolds, I'm dropping it some to make look better. If you go to Carlislie, just look for guy with all the jared bones and dissheveled look.