Napa alternator failures.

Rambro

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Bought a nappa alt with lifetime warranty. It had been going along strong for about a year and this morning it sounded like the bearings took a dump. Get the replacement on and its showing low 13's at start up and its dipping into the high twelves after about a 20 minute drive. Might be time to pony up and get a fancy alt.
 

barstowpo

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All the new rebuilt stuff seems to be terrible. I got 12 starts out of my warranty replaced O'Reilly's starter.
 

Recon

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I don’t buy any electrical parts from any of my local auto parts stores. We’ve had too many issues with reliability. Current out of town parts supplier’s parts are holding up nicely in my opinion. Although they seem to be getting greedy with their sales quota as of late. Or OEM parts are bought but then again I’ve received too many defective dealer parts for my liking. Mainly my GM dealer.


Pick your poison.
 

me32

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All the rebuilt alt for the fords have been just junk. Look into nations and mechman alts
 

01yellercobra

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It's a crap shoot with any of that stuff anymore. I had a refurbished Ford alternator go out after about a year. Probably 7,000ish miles. I bought the parts to rebuild/upgrade a spare I had. The voltage regulator in that kit was bad out of the box. They did replace it under warranty at least. I'm currently running that alternator and it's doing ok (knock on wood), but when it dies I'll probably get a Nations. I like the idea of the regulator being separate from the alternator.
 

ccq8le

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I don't know if you're still using the factory wiring or not but it could be the wires from the Alternator to the Batt fuse box.

I had a similar issue where I thought my alternator was bad again So I ordered and installed a premium Alternator and I would see the battery light come on and go the first week after install (especially after just starting the car). So I went and ordered a new batt (odyssey). Same issue kept happening. I swapped the pulley thinking that was the issue. However it turned out it was that the stock wires were corroded and had what looked like a white powder development to them. The stock wire also has a smaller gauge section to it that was brittle. (I believe is to act as a fuse for it). It has been a while since I changed it though so I don't quite remember.

Worth looking into
 

Rambro

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This first nappa alt was strong. It was always in the mid to high 13's.
 

hotcobra03

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I been using oriellys,,

I have them bench test alt,but a couple times vs just 1..

starters the same..

with mine..I had noticed volts different from battery to inside of car.

was seeing 14+ at battery..12.8 to 13 in car..

I only upgraded ground from battery to radiator.

this put 14 in car now

I had also found..the stud on engine mount was broken..I moved main ground to oil pan..till I get to fix stud.
 

Rambro

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Im getting my readings from a predator. Today it was 13.5 then after about 15 minutes it was jumping around from low 13's to 12.6 at some points. Its about 85 degrees and humid. I didn't have A/C or radio on.
 

jrgoffin

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You can buy brand new V-6 alternators that are a higher quality: just swap the pulley & cable post and you have an instant Terminator version. Otherwise, a custom shop or a 3G conversion is easy.

Plenty on the subject: Electrical
 

Rambro

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Really liking the idea of the nations setup. About how much is that set up with wiring upgrade?
 
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lOOKnGO

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The Napa alts I get are not rebuilt but new repo. I have had problems too. I believe it has more to do with shaft bearing not holding up to tension and spin of blown dohc 4.6


Sent from my iPhone using Tapatalk
 

hotcobra03

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Im getting my readings from a predator. Today it was 13.5 then after about 15 minutes it was jumping around from low 13's to 12.6 at some points. Its about 85 degrees and humid. I didn't have A/C or radio on.
it could be just a ground wire thing.

this is a reading from dlc,which grounds to body of car..not grounded to actual battery..

during tests on mine..I had used jumper cables.and when I clamped ground of battery to car.is when I seen a change..

I found the ground wire was burned inside.


I have used my predator also..
than I use my escort radar detector in volt setting..

after adding a ground I see 14.4 cold,than after warm 13.8 with everything on..

here is a thought..I had worked on a friend's bmw,
his has a v8 with altinator,in the same area,
his has a plastic cover around the back with a cooling shoot to front bumper.they must have the same problem with cooling
 

perry2k12

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When my original alternator failed I installed a lifetime warranty Napa unit and it has been trouble free for about 5 years now. You don't have a different crank pulley that is overspinning the alternator do you?
 

SVTDice

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I'm on my 3rd Napa alt. But honestly, heat kills these things far more than anything else.
 

Rambro

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I have factory lower. The first one was nice and lasted a bit. I dont expect them to last long but this recent one was a bust from the start lol. I'll also look into upgrading those grounds.
 

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