charging problems

[betteranger]

Ill start off by saying I was driving down the freeway when my whining alternator gave it up and became a smoking alternator and while it quit charging, it did continue spinning. I limped it home and the next day I was off to the auto parts store for, u guessed it, an alternator. New alternator installed, I thought that was it but alas, not charging. Back to the parts store to have it tested and its fine, still no charging. Checked fuses and wires for continuity and all seem fine. Obviously Im missing something, anybody here encounter this or similar situation? In a pinch and need to get to work in the am
thanks, Ken

 

[koda2000]

did you check the mega-fuse on the back of the power distribution box?

 

[pbnj22]

What continuity did you check?

 

[betteranger]

I did check the mega fuse across the terminals and continuity from alt. lead to mega fuse terminal

 

[betteranger]

and I also checked the fuses under the hood and all checked ok. I was wondering if there is a fusible link in any of the smaller wires that plug into the alt? I found that the minifuse in position #14 under the hood is for the voltage regulator and was good so back to go, do not collect 200 dollars and penalized 2 or 3 more rolls

 

[jremington59]

Do you have power at the red wire on the back of the alt?

 

[pbnj22]

maybe your batt wont hold a charge? iyou said the auto parts store said the new alt was good.. did they check the batt too?

 

[imp]

maybe your batt wont hold a charge? iyou said the auto parts store said the new alt was good.. did they check the batt too?

If the alternator has output, the battery becomes a boat anchor, so to speak.

I know of no fusing used in the voltage regulator side of the alternator (stator) connection. imp

 

[bill06447]

If the alternator has output, the battery becomes a boat anchor, so to speak.

I know of no fusing used in the voltage regulator side of the alternator (stator) connection. imp

Definitely check your battery. A short in one of the battery cells will smoke the alternator real quick.

Bill

 

[koda2000]

do you have a BATTERY light ON on the instrument cluster? this light must be working (during the bulb check) or your battery will not be charged.

 

[betteranger]

JR 59, when u say "red wire" are you referring to the heavy charging wire or one of the smaller wires in the pigtail?

 

[betteranger]

The battery light in the cluster is lit, I've tried switching out batteries. To Imp, The fuse I listed earlier, #14, was identified on motorcraft site under the owners manual for my vehicle so thats all I have to go on. The only other piece of info I can think of is when this all started, the batt. light went brite and the volt meter spiked just for a split second

 

[koda2000]

you might want to have your new alternator checked. the voltage gauge spiking and the light getting bright might indicate a voltage regulator problem.

 

[pbnj22]

you might want to have your new alternator checked. the voltage gauge spiking and the light getting bright might indicate a voltage regulator problem.

Are these internal regulators or external? if its internal and it goes bad is the entire alt pretty much a boat anchor? and if its external can you bypass it and see if car runs normally?

 

[koda2000]

Are these internal regulators or external? if its internal and it goes bad is the entire alt pretty much a boat anchor? and if its external can you bypass it and see if car runs normally?

well, they're kinda external in that they're mounted on the back of the alternator case, but if you bought a new or reman alternator it would have come with the alternator. it's not like a GM where the regulator is inside the case, but it's not like it's a separate part mounted on the firewall or radiator core. you didn't buy one of the AutoZone Valuecrap remans did you? do you have/own a voltage meter?

 

[penske2584]

If you replace alternator but not battery, then run it and it fails; then replace battery with a now used alternator; then fail again... could it not be failed wiring or ground?

Replace alternator and battery. I hear replacing one and not the other will cause continual failure. I have not had that issue before but maybe you are having it.

Best thing to do is check the fuse rating for the regulator. Too high amps=failure.

Seems to be an issue with jostled ground, cut wiring or arching wires. Clean ground connections.

Check a newer manual for your vehicle for updated issues and recalls.

 

[betteranger]

The truck runs fine, 2 alternators and 2 batteries later and still no charging. the pigtail has 3 wires in it, green, black and yellow, right to left and a single black that connects to a separate pin. What readings should i get from these leads? I also have a '93 f-250 with the same alternator and when I put it on that truck, everything works fine.

 

[koda2000]

replacing a perfectly good battery (tests and load tests GOOD) is a complete waste of money. although a BAD battery can ruin a perfectly good alternator by overworking it. anyway, the OP's problem seems to be that either the alternator is not getting switched ON or the charge is not making it's way to the battery. without a VOM it is not possible to test for this...

1. check for 14'ish volts at the large lug on the back of the alternator w/engine running. if you not seeing charging voltage here, the alternator is not ON. check for battery voltage at the green & red wire at the alternator plug with the key on. power flows through the BATT light to this wire. when the engine starts the ground for the BATT light is disconnected by the voltage regulator. if your BATT light doesn't work, your alternator will not charge. also, if necessary use a jumper cable to ground the alternator case to the engine block to make sure you don't have a ground problem.

2. assuming you had 14'ish volts at the alternator, next check the voltage at BOTH sides of the mega-fuse. if you don't have the same voltage at both sides of the mega-fuse, replace it.

3. if you have 14'ish voltage at both sides of the mega fuse, start checking wires back to the battery including battery cables and clamps.

 

[imp]

Alternator diagram

Assuming your working on a '99 Ranger? Below is the Ford Shop Manual Charging System schematic for '96 F-Series trucks. The wire colors may not be identical, but at least you can see what-the-hell is being talked about. imp

 

[jremington59]

Does your alternator have the built in voltage regulator? As Koda stated, the voltage spike seems like a regulator problem. Have you actually checked the voltage at the battery with the vehicle running?