1990 2.3 alternators

[AFricks88]

What alternator is everyone using on a 1990 2.3 ranger? My uncles finally puked yesterday and no parts store had one in stock but was able to get a reman from oreillys. It comes with 3 wires coming out of it that requires cutting off your factory plug and spicing and crimping those wires to new alternator wires. What happened to just unplug and plug back up? Can anyone explain this to me? Because if the alternator is bad gonna have to cut wires and re splice!

 

[sgtsandman]

I can’t explain the why but I wouldn’t splice the wires. I would install a waterproof plug on both sides instead. It will take a little more time and add to the cost but it will be a “one and done” for the harness side of things and gives you the ability to disconnect for troubleshooting, if it’s ever needed.

 

[RonD]

Where do you live?

Most cities will have a starter and alternator rebuild shop
Some times they will have OEM ready to go and just swap with you or it will be a few days to get yours cleaned and rebuilt

All alternators will have a B+ terminal, larger wire(or 2 wires) can be a plug or a stud/nut terminal, this wire has 12volt all the time so make sure not to short it or better yet unhook battery cable before starting

Then there will be Voltage Regulator plug, can be 2 or 3 wire, 3rd wire is short jumper for stator connection, plugs into single terminal on alternator, usually a white wire
2 wire version has internal stator connection

One of the remaining 2 wires is for Monitor circuit, usually yellow wire, will have 12volts all the time, hooked to a fuse in engine fuse box

Next wire, usually green, is Battery Light wire, and the ON/OFF switch for alternator, only has 12v with key on, 12v comes from ignition switch in the cab, THRU the Battery Light bulb

Test these wires with volt meter with battery connected before starting the swap, it can be just a blown fuse when alternator stops working

 

[tomw]

Doing most repairs on alternators is relatively simple. The exception is damaged windings in the stator or rotor.
Failing parts that are available, and likely more than is replaced in 're-man' alternators are:
front and rear bearings
diode array
brushes
regulator
The diode array is likely soldered, so you must have a LARGE soldering iron to disconnect/re-solder.
All else is normal 'stuff'.
People seem afraid to look inside. They shouldn't be.
If *I* do the repairs, I know what was replaced vs what was bad. I have replaced brushes and added
grease to bearings before they got dried out and ruined. Still have the factory in the two I have done,
on an 87 Vulcan with 250,000 and the other an 85 with a 2.3. The latter god 'sudzed' and the grease
erased from the bearings... but works now.
Newer systems have computer (ECM) monitoring and output 'setting' in some cases. Not much different except for the regulator involved and you need to get the correct one if you replace.
tom

 

[Shran]

So here's the deal with these alternators, they are internally identical to the V6 & V8 alternators (assuming same amperage) but the mounting ears are in different locations and the pulleys can be different. I have a pile of various alternators on hand and I can almost always swap parts from most late 80's/early 90's Ford trucks & cars to make one that works. 4 cylinder Ranger parts are somewhat hard to come by in general and that is why you are running into problems finding the right one in stock.

I have had mine rebuilt several times by a local shop and the first time, it came with that plug to replace. They said that it absolutely must be done because it melts internally or builds up resistance and pooches the alternator or something like that. Doubt that is 100% true but it won't hurt to replace it.

 

[Josh B]

I got 3 or 4 from the wrecking yard when messing around over there
I'm afraid their prices and policies have changed since, well, you know when

 

[AFricks88]

Thanks for the insight guys. I absolutely hate the idea of cutting a factory plug.

 

[ummduh]

Thanks for the insight guys. I absolutely hate the idea of cutting a factory plug.

If it's the one I am thinking it is, the charge wire is in that plug. What happens is that it makes a poor connection over time, which causes the plug to get hot, which causes a worse connection, which causes more heat... And eventually it starts on fire. This is a very well documented issue back in that era.

When an aftermarket part comes with a replacement pigtail it's almost always in your best interest to replace it.

edit: yea, looked the alt up. REPLACE IT! Those are the fire starters.

edit edit: sounds like you're saying it has leads coming right off the alt without the plug. That's probably to keep from people from going "my plug looks fine, i don't need to replace it this time" and burning their vehicle down. Looking on RA there are plenty that still use the plug though, you could find a different brand if you don't want to go the hardwire route.