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Electrical Glowing alternator wires

  • Thread starter Thread starter jstang209
  • Start date Start date Apr 7, 2023
J

jstang209

20+ Year Stangneter
Jun 3, 2004
640
2
18
Stockton 209
Apr 7, 2023
#1
  • Apr 7, 2023
  • #1
I didn’t get a pic with them super hot but can anyone advise on what I have going on here?
 

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Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,218
17,901
224
Massachusetts
Apr 7, 2023
#2
  • Apr 7, 2023
  • #2
High amperage going through the wires, or a high resistance connection.

With the 130A alt, the #10 wires should not be used at all. Cut them back and tape into the harness. The #4 wire should all that is connected to the power lug and connected to the distribution block inside the fender (i assume).

As to why it's getting hot? You either have a TON of amps going through that wire and terminal, or the connection itself is really poor/loose. I've seen crimped style connectors like that done so poorly they barely squeeze the wire and/or make minimal contact with the copper or even corrode internally. Loose/poor connection causes high resistance and creates heat.

Do you have a fuse on the alt wire? If so, what size? #4 wire, depending on lenght of run, ambient temp, and if 90*C or 60*C wire is used, is really only rated around 100amps. I often see folks assume 130A alt means fuse at 130A, and that may be entirely too big for the wire size.
 

AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
Oct 28, 2001
5,826
3,960
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Claremore, OK
Apr 7, 2023
#3
  • Apr 7, 2023
  • #3
My guess would be that the connection on the back of the alternator was not tight. The arcing going on there to eat away at the stud pretty much indicates that and this will produce a lot of heat. I would suggest you take a look a this thread and start from scratch.

1989 5.0 3g Alternator Conversion.

Im fairly certain i have all the information i need but have a question unique to my circumstances. ive always had a charging issue with this car and its been in the shop years ago because i wasnt confident enough to get at it myself. either way the issue i had was fixed for a little while but...
stangnet.com
 
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J

jstang209

20+ Year Stangneter
Jun 3, 2004
640
2
18
Stockton 209
Apr 7, 2023
#4
  • Apr 7, 2023
  • #4
Mustang5L5 said:
High amperage going through the wires, or a high resistance connection.

With the 130A alt, the #10 wires should not be used at all. Cut them back and tape into the harness. The #4 wire should all that is connected to the power lug and connected to the distribution block inside the fender (i assume).

As to why it's getting hot? You either have a TON of amps going through that wire and terminal, or the connection itself is really poor/loose. I've seen crimped style connectors like that done so poorly they barely squeeze the wire and/or make minimal contact with the copper or even corrode internally. Loose/poor connection causes high resistance and creates heat.

Do you have a fuse on the alt wire? If so, what size? #4 wire, depending on lenght of run, ambient temp, and if 90*C or 60*C wire is used, is really only rated around 100amps. I often see folks assume 130A alt means fuse at 130A, and that may be entirely too big for the wire size.
Click to expand...
When you say the #10 wires are you referring to the blue and yellow ring terminals? Those are def not 10g maybe 18. The red one goes directly to the starter solenoid with a 200amp in line fuse. Are you saying I only need the red one connected to the alternator? Those other two I can tape into the harness?
 

AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
Oct 28, 2001
5,826
3,960
183
Claremore, OK
Apr 7, 2023
#5
  • Apr 7, 2023
  • #5
All of that is answered by jrichker in the thread I posted above.
 
Reactions: jstang209

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,218
17,901
224
Massachusetts
Apr 7, 2023
#6
  • Apr 7, 2023
  • #6
Yes, the Orange w/black stripe wires. Do not hook those up. They are not sized appropriately to handle the increased potential load when going from 75a to a 130A alt. It's entirely possible that it is these 2 wires that are heating up from load. One of them is also broken, which isn't helping the situation.

They must remain hooked up at the starter solenoid however, as the voltage regulator is powered off one of them halfway between the alt and the starter solenoid connection.

200A fuse is too big for #4 wire. You can probably get away with a 120/125A fuse on #4
 
Reactions: jstang209

AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
Oct 28, 2001
5,826
3,960
183
Claremore, OK
Apr 7, 2023
#7
  • Apr 7, 2023
  • #7
Wafer fuse holders:

02981001ZXT Littelfuse MEGA® Fuse Holder, 500A/32V

Littelfuse 02981001ZXT MEGA® fuse holder with cover, black, 500A/32V.
www.waytekwire.com

125A wafer fuse (get two so you have a spare):

Littelfuse 0298125.ZXEH Riveted MEGA® Fuse | Waytek

Littelfuse 0298125.ZXEH Riveted MEGA® Fuse 32V, 125A is in stock and ready to ship. Purchase today!
www.waytekwire.com
 
Reactions: jstang209

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,218
17,901
224
Massachusetts
Apr 7, 2023
#8
  • Apr 7, 2023
  • #8
That's the exact same fuse I run on my 130A alt setup with 4G wire. Bought a spare and keep it in the glovebox.

I've actually measured current draw on my car. Stockish setup electrically with a contour dual fan. Lights on, heat on, wipers, hazards, reverse lights, etc and fan on full....85-90amps.

Realistically, most folks arent going to drive around with EVERY single electrical accessory on.
 
Reactions: AeroCoupe

AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
Oct 28, 2001
5,826
3,960
183
Claremore, OK
Apr 7, 2023
#9
  • Apr 7, 2023
  • #9
It’s what I run on the Coupe, T-Bird and on the stereo in the F150.
 

85GTStangGuy

5 Year Member
May 19, 2021
998
625
113
Jax, Florida
Apr 7, 2023
#10
  • Apr 7, 2023
  • #10
Also, I definitely see corrosion on some of those wires/terminals. That'll increase resistance..... certainly not good for any connection. Either clean them up good, or it may be necessary to trim the wire(s) back a bit and put on new terminal(s). That may a good idea to do anyway.
 

AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
Oct 28, 2001
5,826
3,960
183
Claremore, OK
Apr 7, 2023
#11
  • Apr 7, 2023
  • #11
I’d just start over so you know it’s 100%. Wire is cheap but a fire isn’t.

Make sure your grounds are good and that you have a 4 ga from the block to the frame and frame to the battery.
 
Reactions: 85GTStangGuy, JAA, limp and 1 other person
J

Jarhead67

5 Year Member
Nov 24, 2018
171
63
38
Windsor Locks, Connecticut
Apr 8, 2023
#12
  • Apr 8, 2023
  • #12
jstang209 said:
When you say the #10 wires are you referring to the blue and yellow ring terminals? Those are def not 10g maybe 18. The red one goes directly to the starter solenoid with a 200amp in line fuse. Are you saying I only need the red one connected to the alternator? Those other two I can tape into the harness?
Click to expand...
The two you cut are 10g black with orange stripe.
 
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