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2G Alternator not charging on my 1986 F150 5.0

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Socnarftrucks

2G Alternator not charging on my 1986 F150 5.0

Accidentally dropped my OEM alternator and smashed the regulator. Went to Oreilly's and purchased a remanufactured one (60 A) which included one of the pigtails . I ensured the connections were done correctly and checked the path of the wires all the way to the starter relay; no damaged or frayed wires.

I have a brand new battery and it will invariably die after a couple of hours of use. Any help would be appreciated, switching to a 3G is beyond my electrical comfort level..... TIA.

Gary Lewis

Re: 2G Alternator not charging on my 1986 F150 5.0

Administrator

Do you know the alternator isn't charging? In other words, are you charging the battery at home and then the truck dies after driving?

Do you have a volt meter?

Can you show us a pic of the back of the alternator showing how it is wired?

Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

Socnarftrucks

Re: 2G Alternator not charging on my 1986 F150 5.0

Yes, I don’t believe it’s charging. The trucks battery dies even after fully charged will die after a couple of days and/or a few cranks. If we jump it, it will run but dies after we disconnect the battery. I have swapped batteries with my brothers truck which is an identical 86 and the same thing happens. Pic of alternator coming up….

Socnarftrucks

Re: 2G Alternator not charging on my 1986 F150 5.0

In reply to this post by Gary Lewis

The two black wires were connected to the black and orange from the harness. The other connector is a yellow/white and green/red from the harness.

Socnarftrucks

Re: 2G Alternator not charging on my 1986 F150 5.0

In reply to this post by Gary Lewis

Forgot to mention that the small white/black wire goes to what I believe it’s the choke connector which is not connected to anything….

ArdWrknTrk

Re: 2G Alternator not charging on my 1986 F150 5.0

Administrator

In reply to this post by Socnarftrucks

"New" (rebuilt) doesn't necessarily mean good!
Was the alternator tested in the store when you bought it?

Gary has sworn off O'Reilly's alternators after the church car came back... twice.

Do you have a multimeter?
Do you have power at the lt gr/red wire with the key in run?

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

Gary Lewis

Re: 2G Alternator not charging on my 1986 F150 5.0

Administrator

Yes, I'm not going to buy another alternator from O'Reilly's!!!! Two out of four were bad, and one was bad out of the box.

Gary, AKA "Gary fellow": Profile

Socnarftrucks

Re: 2G Alternator not charging on my 1986 F150 5.0

No, it wasn’t tested. Yes, there is power to the green/red with the key on. And power to the black/orange without. I’m on my way to the store to have it bench tested (assuming the kid will know how) and/or get my money back.

Gary Lewis

Re: 2G Alternator not charging on my 1986 F150 5.0

Administrator

The testing machine in our O'Reilly's has been down for months.

Gary, AKA "Gary fellow": Profile

ArdWrknTrk

Re: 2G Alternator not charging on my 1986 F150 5.0

Administrator

In reply to this post by Socnarftrucks

The twin bk/or wires are connected to battery + through a fusible link.
So you have proven the fuse link is still good.

With a meter in hand I think I would have tried to force the alternator to charge @ full field (ground here to test)

I've got nothing to say about O'Reilly's, (because there isn't one local to me) but my 2G was nothing but trouble and I'm glad I finally got rid of it.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

Socnarftrucks

Re: 2G Alternator not charging on my 1986 F150 5.0

In reply to this post by Gary Lewis

2 for 2 …..

ArdWrknTrk

Re: 2G Alternator not charging on my 1986 F150 5.0

Administrator

At least they had a tester that works.
Gary had to get them home and installed to know they were garbage.

Honestly, I'd just buy a new alternator from DB or someone.
It's got to be better than crappy rebuilds from a chain store.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

Gary Lewis

Re: 2G Alternator not charging on my 1986 F150 5.0

Administrator

In reply to this post by Socnarftrucks

Are you saying that not only was yours bad but the next one they pulled out of a box was bad????

Gary, AKA "Gary fellow": Profile

Socnarftrucks

Re: 2G Alternator not charging on my 1986 F150 5.0

The first one I bought was never tested at the store, so when the issue started, we concluded we had a bad one. The store manager agreed with our assessment and replaced it. The replacement behaved the same way, and I thought the odds of having two bad ones back to back were not good, hence my post on BNF. I guess my reluctance to believe those replacements were garbage bit me in the derrière. Going in a different direction, probable DB this time. Or maybe a 3G but I need to sit down and read Gary’s instructions. Many thanks!!!!

Socnarftrucks

Re: 2G Alternator not charging on my 1986 F150 5.0

In reply to this post by Gary Lewis

All this happened within a week mind you!!

ArdWrknTrk

Re: 2G Alternator not charging on my 1986 F150 5.0

Administrator

In reply to this post by Socnarftrucks

Does your 1986 5.0 have efi and a serpentine belt? (I see a V-belt pulley in your photo)

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

Gary Lewis

Re: 2G Alternator not charging on my 1986 F150 5.0

Administrator

In reply to this post by Socnarftrucks

Wow! This is unbelievable! I'm going to post Don't Buy An O'Reilly's Alternator in the main section.

Gary, AKA "Gary fellow": Profile

Socnarftrucks

Re: 2G Alternator not charging on my 1986 F150 5.0

In reply to this post by ArdWrknTrk

The truck is a 5.0 EFI and does not have a serpentine belt. I had to swap the pulley.

ArdWrknTrk

Re: 2G Alternator not charging on my 1986 F150 5.0

Administrator

The DB 400-14149 is said to be for your application but the rear is clocked 120° further than what you show.

Amazon would have it to me tomorrow for $104 outright if I order within the next 2:21

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

Socnarftrucks

Re: 2G Alternator not charging on my 1986 F150 5.0

I’m done with Oreilly, I’ll be ordering the DB. Thanks