Installed new alternator. SMOKE

[GBODY_]

Installed new bosch alternator and the battedy terms were sparking like crazy when i was trying to reconnect them. Then smoke billowed out of my alternator. Turns out the large brown ground wire from motor to alt came loose from its clamp on motor side. And grounded itself.... hoping i didnt just fry brand new VR..does anyone know the part number for that ground wire.

[pete3799]

A ground wire grounding itself won't cause that.
You sure the reds are on B+ and the browns are on neg.? Or you hooked the battery up backwards?

[GBODY_]

Battery is correct orientation. I installed everything before, and didnt install fan extension, people on another forum suggested i install the fan extension. So i pulled everything part, and dinit all again installing the fan extension fin cone. And then this happens. Im kinda at a loss.

[GBODY_]

Also the post i put the 2 brown wires on was labeled BR by rebuilder.

[Tom_in_NH]

BR doesn't designate BROWN. It usually designates the main output terminal of the alternator.

[GBODY_]

Wait so what does that mean

[GBODY_]

I just double checked, and the wires were run correctly

[E Sully]

Here's the ground wire. Part number #911 612 233 00
If it helps here's a picture of my '86 alternator wiring, although from what I can see yous seems correct. It doesn't make sense though for it to short out by grounding the ground wire. Did it touch one of the Red 12V wires?

[GBODY_]

Originally Posted by E Sully

Here's the ground wire. Part number #911 612 233 00
If it helps here's a picture of my '86 alternator wiring, although from what I can see yous seems correct. It doesn't make sense though for it to short out by grounding the ground wire. Did it touch one of the Red 12V wires?

The ground strap wire that melted and smoked out because disconnected from the eyelet thats attached to motor. Cause a loose haphazard connection. Im 90% certain that breached connection is what did it. After removing the rotten ground wire i touched pos lead of battery back to post and there was no sparking or smells or smoke.

I ordered a replacement wire from pelican... now i wait, really really really hope i didnt damage new alt or VR.

Car is a '87 911

[pmax]

B+ Positive (Red)

[pmax]

Where's the nut and washer securing the wires to the terminal ?

[HarryD]

Hope you had no damage.

However, letting the magic smoke out is almost always a bad. If you had a British Car you could use this to restore the system.

[grb008]

@harryD That is classic. I have bottles of those for my MG.

[john walker's workshop]

The housing grounds the alternator body and the fat brown ground wire to the engine case is just to make sure. If there's a ton of corrosion on or in the housing or on the engine case where the housing contacts, the ground is compromised and the extra wire becomes more important, so you might want to clean things up if needed.

[pmax]

Originally Posted by GBODY_

Im 90% certain that breached connection is what did it. After removing the rotten ground wire i touched pos lead of battery back to post and there was no sparking or smells or smoke.

I ordered a replacement wire from pelican... now i wait, really really really hope i didnt damage new alt or VR.

Car is a '87 911

Tread carefully before trying more "what if I do this" experiments. Don't assume there's no other damage to the harness waiting to short out.