[Firaga]

I'm driving to work last night and I notice my lights seemed a bit dim, and as I got to work I noticed my voltage gauge was at about half of where it normally is so I'm figuring the battery is dying. Looks like I'd see about a new one when I get home in the morning.
I'm driving up my hill and all of a sudden my cluster shuts off for a second then dims back on and my volt gauge gets to normal for about 2 seconds. I get to my house and all of a sudden my car is smoking, so I park it and open my hood real quick.

My alternator was a-blaze! So I ran and grabbed a fire extinguisher put it out. Looks like the fire started on the rectifier plug. It was melted into the alternator. I had to pry it out with a screwdriver. Ughh.

Apparently Kragen doesn't sell them so I'll have to order one online because I'd rather not get a junkyard one.

Anybody have any advice on how to make this new one NOT catch fire?

[Mr_Will]

do you have a 3g upgrade
if not, that is how you make it not catch fire

[flyin ryan]

pretty common with stockers from what i've read on the corral although i've had four foxes and never had a melt down like that of a stock alt myself.

[Firaga]

I'm not sure how to tell if it's a 3g or not. Kragen sold me some Autolite one. I dont have the box anymore because I gave it back to them for the core.

[flyin ryan]

Originally Posted by Firaga I'm not sure how to tell if it's a 3g or not. Kragen sold me some Autolite one. I dont have the box anymore because I gave it back to them for the core.

stock 2g type has the fan on the out side of the front of the case where as the 3g has it internally.

here's a pic... the left one is the 3g

[nolife]

Mine did the same but the burning was a little further up the cable. I saw a fox parked in a lot with no one around burning once on a cop show. my guess it was that pigtial. That design with the 2 1/4 connectors inside that plug that merges to a single 8/10 gauge wire that runs to the solenoid is a fucking joke. That plug should ALWAYS be replaced and with new dielectric grease when a new alt is installed and everyone should inspect that thing or replace it every few years. Most auto stores have them even though some say they don't, I've found them on the shelf with the other electrical plugs and crap. Even with replacing that connector though, some of the replacement pigtails are crimp style which are a hazard as well and develop a resistance from corrosion too. Like I said, the whole setup is a fucking rig job Ford should never have used. The better route is the 3g that has a terminal lug instead of that connector and you can use a new 4 gauge wire directly to a fusable link or a AGU fuse at the solenoid.

In fact, now that you brought this up again. I think I'm done risking it with both of my 2g's in my foxes. I'm switching...

[Firaga]

Looks like I got another 2g... :-/

[Firaga]

UPDATE:
Installed Alt, so far it seems okay, but then I realized my negative battery cable was messed up and way loose off of the battery.

Would I be correct in assuming that when I gave it a hard accel up the hill, to make up for the loss in power coming from the battery due to a loose connection it overpowered the alternator, thus setting the fire?

Either way, getting 2 new battery cables today.

[nolife]

Originally Posted by Firaga UPDATE: Installed Alt, so far it seems okay, but then I realized my negative battery cable was messed up and way loose off of the battery. Would I be correct in assuming that when I gave it a hard accel up the hill, to make up for the loss in power coming from the battery due to a loose connection it overpowered the alternator, thus setting the fire?

No. It might have triggered some weird event but regardless, an alternator putting out its max current should NEVER burn up the connector. Those connectors are a faulty design and they corrode over time. Just like the faulty headlight switch failure common in a lot of Fords including some year Fox mustangs.

[Firaga]

Alright, finding a slew of problems now.

Water pump leaks from some hole in the bottom...

Also, at an idle the car stays at about 12 volts. However with the headlights on, it drops to about 11.20 and sometimes lower.

It never did this before, I don't know the exact voltage, but the nedle was about halfway in the gauge. However, I'm thinking the gauge was faulty, since the tach was messed up and kept a "high idle"


What's the normal running voltage for this car at idle? And is there a reason it's dipping so low?
And do I need a new water pump?

[McMustang5.0]

you need a new water pump! At idle my 84 has around 13V's.