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Alternator problems on 1994-5 Windstar 3.8

Hi - Thanks for those who have created this group. Being a Windstar owner, this should be a great help for a limited DIY repair attempter who used to work on his own vehicles that were made prior to

1970 but now is completely baffled by the complexity and sometimes insane non-access for troubleshooting or the construction being such that one needs to drop the engine in order to dump the ashtray type of difficulty of new "modern" made cars. %-!)

The problem I'm having is not being able to get an alternator to work. The one with the van originally was charging but not completely, then it stopped charging altogether. So I installed a rebuilt one from Autozone. Took a reading and was getting 14 volts at the battery and thought alright, back to driving again. The next day however, I couldn't start the van. Took a reading on the battery and it was only

9 volts. Got a replacement, put that in after charging the battery and it only put out 12 volts and not the specified 14. Went to a junkyard and only got 12 volts out of that one too!

Can't really afford a brand new one from the dealership which would most likely work like a charm, but here's the issue: I can't believe I'm having that much bad luck with 3 different alternators. But having looked at the manual and having tested continuity for fuses and fusable links, I see no other thing that could keep any alternator from putting out 14 volts. The belt is tight, the fluids like oil and power steering are a bit low, but I'm in south Louisiana so the motor oil is not sludge, there is no ammeter or voltmeter in the dash and the idiot light doesn't come on but this was bought from a used car dealer in northern Florida so there is no telling if the bulb is missing or not and it shouldn't prevent the alternator from charging if blown, right? Or am I wrong about that?

So, do any of you have *any* ideas as to what my problem is if it's simply not a matter of bad luck?

ANY and ALL assistance will be GREATLY appreciated!

KBG

Reply to
Elvis Kabong
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I assumed you cleaned the battery cables. and checked the battery hot and ground where they connect to the engine.

Assuming an alternator with a built in voltage regulator, it should be

14/14.5 volts charging or so.

The battery should be 12.6 or so static when charged.

What i think you have is a parasitic drain on the van. Meaning something is draining the battery overnight. maybe even a under hood or glove box light.

You need someone to measure current draw with the van off and not running. you could try unhooking the battery overnight, then re connecting it and see if the van starts. If it does, something is draining it.

Bob

Reply to
Bob Urz

Thanks for replying Bob, but I'm telling you, I took readings at the output of each of the 3 different alternators while the engine was running on each occasion it was not reading 14-14.5 volts except for the very first replacement right after it was installed. But the next day, the battery only read 9 volts. So, I charged up the battery then installed another alternator and it only read

12 volts while running and same with the third alternator. However, I really need to perform the test you recommend. Time to pull out the ol' ammeter.

Thanks again,

KBG

Reply to
Elvis Kabong

"Elvis Kabong" wrote: (1994-5 Windstar 3.8)

The original alternator was charging but not completely, then it stopped charging altogether.

I installed an Autozone rebuilt and it put out 14 volts at the battery. The next day the van wouldn't start, and the battery was at 9 volts. I recharged the battery and installed a second alternator but it only put out 12 volts. I installed a third alternator from the junkyard and only got 12 volts out of that one.

I see nothing that could keep any alternator from putting out 14 volts. Any ideas as to what is the problem? _______________________________________________

A good battery will maintain 12 volts even if it is almost completely discharged. A bad battery with a shorted cell will maintain 9 volts until an alternator tries to charge it to 14 volts. The battery's huge internal power drain will prevent the voltage from fully developing, and the overload will damage the alternator trying to charge it. If this is the case, the battery needs replacement.

If the battery is good (12 volts) and the alternator output reads only 12 volts, the alternator is not putting out anything. If it's a good alternator, the problem is in the wiring - possibly the field energizing wires are broken or are not being energized by the ignition.

Good luck.

Rodan.

Reply to
Rodan

i havent had luck with autozone starters and alternaters. you might try napa .. a new voltage regulator usually goes in when i replace lt.

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Reply to
ds549

Must be a 95 Windstar since they didn't _make_ a 94 Windstar...

Me either. More likely a wiring problem that you have yet to identify and solve.

The warning bulb circuit -HAS- to be functional for the alternator to work. The warning bulb circuit is the only alternator circuit that is switched by the ignition switch, thus, it is necessary that it functions so that the field circuit is excited and the voltage regulator be switched on.

Lots of ideas. Test the black/orange output wire to make certain there is battery voltage available. The black/orange is protected by two fusible links. Test at the yellow wire for battery voltage, this is the sensing circuit, it is protected by fuse "T" in the underhood fuse block. With the key on, test for 12 volts at the lt green/red wire, this is the warning lamp circuit, it is protected by fuse "14" in the IP fuse block. Not a very complicated or sophisticated charging system, only three critical circuits that need to be checked.

As mentioned by someone else, check for parasitic draw, there's no sense in hanging alternators if something is dragging the battery down overnight and then overloading the alternator trying to bring the battery back up.

Look at the back of the alternator, there are two screws that fasten the voltage regulator and brush holder to the case, one screw is marked "F" one screw is marked "A". Jumpering the "F" screw to ground will full field the alternator bypassing the voltage regulator. If you have voltage everywhere you should, jumpering the "F" terminal should produce 14 volts from the alternator.

Reply to
aarcuda69062

In 1985 when I worked at Western Auto, Every alternator I sold included a new voltage regulator built in. Rebuilding one without replacing the rectifier unit is not rebuilding .

Reply to
Shawn

Thanks to all of you for the excellent informative answers. Will be installing a 4th alternator tomorrow and applying some of these test procedures.

BTW aarcuda69062, the van is a 95 but was made on 04/94.

Autozone - never again for major car parts. Fluids, lamps, fuses etc., yes, but no mo parts for now on!

Happy muffler bearings everyone!

Reply to
Elvis Kabong

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