EDIT: Has anyone put a truck alternator on their F body down in the stock location? Does the exciter wire plug ( the small plug ) plug right in and operate the alternator properly? In this link below it says it will bolt right up and that they make a heavy duty version but im thinking the truck one would already be heavier duty than the F body alt.

http://www.alternatorparts.com/ad_al...order_page.htm



My car is eating alternators like there is not friggin tomorrow, the last one went out yesterday, lasted two and a half weeks... This is I believe alternator number 7 or 8 since late 2008.

I have a system, but only one 200 watt amp, nothing major, the tune is set to where the fans run at operating temp at low speed.

It runs a constant 22 amp out of the alternator when the car is running at idle with fans on at low speed. With the a/c on high and lights on it runs at 55 or so amps at idle. The stereo system max amp draw is around 30-35 amps but that is in surges and only at max volume and hard hitting songs.. It has spiked to 40 but not normally. So with everything running a/c on high headlights foglights and stereo all the way up it was at 80 amps out of the alternator. And this is on a 105 amp alt

All the replacement alternators except the last one struggled at idle with the headlights on and especially with headlights and a/c on, above idle was ok.

The last alternator handled the system, a/c, headlights well just didn't last long.

I do NOT have underdrive pulley etc, idle is 700 RPM and alternators have came from 4 different places so im stumped.

My only conclusion is that replacement alternators for these cars just plain suck.

My buddy said my 6700 RPM revlimit is most likely what is knocking out the alternator, he said he fried a bunch of them when revving to 7500, said he put a larger pulley on the alternator to slow it down and didnt have any more problems..

Anyone else have frequent or repeat alternator failures?? Anyone notice RPM related failures??

( does this belong in general maintenance? figured I would get better responses here )

 

I had the same problem with mine. I had it upgraded at a alt repair shop made it into a one wire alt.

 

What brand alternator are you using? Duralast and most all of the repops suck. If you are regularly touching 6500rpms+, that can kill them for sure. Is your power steering leaking on the damn thing? Also a common problem.

Your best solution is a quality one, HO or standard, rebuilt locally. I'd do a HO unit with a bigger pulley to slow it down. That way, you get good current at your lower alternator RPMs.

Good luck!

 

Thanks guys, I would say it semi regularly touches 6500+ jmil... It popped at the track yesterday and everyonce in a while it gets a lil romp here and there. I have used autozone, oreilly, a private distributor that offers a different brand and NAPA so far. I was thinking of using OEM but I would really be pissed if I burnt up a 400 dollar one that I know would be hell to warranty. Besides they are cheaper to order online OEM and that would be hell sending it off etc.. So I buy them at the parts house so I can just take it and swap it.

Ok so now I guess I need to find an alternator man.. I work in Dallas and live just east of Dallas in Rowlett, its between Garland and Rockwall, any suggestions?


OH and the P/S pump WAS leaking thats what happened to the original alt, its dry as can be now.. The alternators dont even have a chance to get dirt on them before im taking them back much less any fluid, but I have resealed the engine and P/S on my car so there aren't any leaks anyway.

 

So now im thinking of just putting an underdrive on it, more power less alternator RPM's may kill two birds with one stone

 

I have an under drive crank pulley & Alt overdrive pulley(on stock idle) with a 350rms amp & sub(2ohms). My volt gauge will drop near the red whenever I'm blasting the music on a red light. I"m sure raising the idle would help me, so if you go with an under drive I would highly recommend you to raise the idle.

 

So basically you made the alternator stay spinning near stock speed and it drops to red, mine did that with all alternators except the last one, and I dont remember about the OE one that went out.... But they do that for a while and then just quit...


Yesterday it was just fine and I actually took the system out, drove to the track, and the radio was left off and it took a crap during a pass at the track, I came up the return lane and it was at 12 volts.

 

i spoke with a alternator guy......he suggested getting the AD244 to replace the CS130.....as soon as i get some funds.......doing the swap

 

Where are you getting your alternator from? if it's NAPA, that's the problem right there. NAPA alts and starters aren't that great. I went thru a couple of them quick with my firebird.

 

Is that the truck alternator?? I dont know what the AD244 is.. Any more details on that?

Well thats the funny part, the NAPA alternators so far have done the best out of the other brands I have tried. I have gotten them in new and rebuilt versions from 4 different companies. None have held longer than roughly 5 months. One literally lasted less than 10 minutes. I have checked EVERYTHING on my car. There is no excessive amp draw or wiring problems. I ohmed out all the hot wires and ground wires. I made sure the alternator is grounding to the brackets properly. All my wiring and alternator case have .4 ohms or less resistance between the test point and battery post..

I talked to a couple more people today and they say that RPM's are not killing the alternator, one of the guys knows more about F body building and turning high RPM's than just about anyone... So again I am stumped.

I did put on another alternator tonight. At idle with the fans on low the alternator is only putting out 22 amps and 21 of those were going to the fuse box which means the battery is only drawing 1 amp. I have seen funky batterys draw alot of amperage and cause repeat alternator failure but I dont have any of the issues I have seen cause repeat failures and I have been a tech for 12 years.. 20 amps is nothing for the alternator to handle. With everything on high: a/c, fan blower, headlights, system as loud as it can go.. it draws 80 amps, so its getting up there but thats at idle and the alternator is a 105 amp..

I really think its just that I am not getting a quality alternator but after talking to a guy that knows his **** he had 1 other F body do the same thing to OE alternators and aftermarket ones and the owner ended up parting out the car and never found a cure, the owner of the car had replaced all wiring etc..

I have checked all my wiring and replaced the wiring pigtail for the exciter wire that energizes the alternator.

If RPM's are not killing the alternator then its just that they are crap. I was mostly starting this to see if anyone has had failures due to RPM, which a buddy of mine had multiple failures until he put a underdrive alternator pulley on and was revving to 7500 and said ever since the underdrive alternator pulley he has not had an issue

 

its the truck 1..........he says the biggest advantage is that it puts out almost twice the amps at lower RPMs than the CS130....and the rectifier is diff design..........the CS130 rectifier on the back is the reason it craps out........of course dont get a stock 1..........get a built 1.....it is a little bigger.........but it will fit in the bracket.......dont know yet how well it clears the PS lines yet......will know when i finally do it

 

Thank you, keep me updated when you do it man im interested to know.

Anyone else have repeat failures?

 

This may be the solution...?

http://www.alternatorparts.com/ad_al...order_page.htm

 

I wanted it to spin near stock speed, but its not. I need to raise my idle to compensate. I don't want to raise my idle so I will just get me the truck alternator. Guys post an update of the swap

 

I have the AD244 HD-140, http://www.alternatorparts.com/

Yes it fits, but you will not be able to use the rear 3rd bolt & rear bracket.
also no different belt is needed. I am already going to send it back for repairs and upgrade to 200amp brigde rectifier plus a better stator for lower rpm's after 1 weeks of use.

Pros- it fixed the interior lights flickering while driving at night.
Highways speeds it sets at 14 volts all day long.

Cons- As soon as the vehicle gets hot at idle rpm, the voltage falls on its face A/C off, it seems I already lost 1 of the 3 "legs"
it should not fall to 11.80 volts ever, whatever the case its under warranty.

Hope you have better luck than me, I would recommend the 200 amp alt... plus a larger alt... current wire.

 

I have the same problem.

 

i think the stock 244 is 140 amps??? no???........and even the 130 would benefit from a bigger batt wire...0 guage if ya got it

 

I upgraded the big3 with 4gauge and made the wires the shortest possible. Doing the big3 helped, because my gauge would go down to the red even when I was cruising, now it only does it at idle. It only does this when I'm bumping some music. 00pooterSS if you get the alternator post an update of the results. Does our Alt. use the 4pin connector?

 

Me 3, except the last two alternators from NAPA, all the other brands (not from NAPA) went to redline at idle with a/c and headlights on

Curious too

Big 3? the alt to batt, block ground, fuse box wire????

I considered doing that.

If I do do the alt I will definately update this thread

 

ive used a autozone reman and have gone threw 3 alts in one week because the crappy remans had a piece of epoxy that would come loose literally after installing them,ive had one come out of the box and fail. im going to upgrade to a brand new one not a reman and that should hopefully fix my problem.

but if a truck one will work ill use that because ive used just the 2 bolts up front on my last motor without any issues