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Alternator batt post red hot

  • Thread starter Thread starter JD1964
  • Start date Start date Jul 4, 2018
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jrichker

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#41
  • Jul 12, 2018
  • #41
http://www.stangnet.com/mustang-forums/threads/3g-alternator-install-a-how-to.646825/#post-6673702
Alternator wiring.

Alternator wiring diagram for 87-93 Mustangs.






Starter solenoid wiring 86-91 model cars.

Connect the fused 4 gauge wire to the alternator and the battery side of the starter solenoid.


Starter solenoid wiring 92-93 model cars.
 

RangerJoe

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Jul 13, 2018
#42
  • Jul 13, 2018
  • #42
Late to the party. I do not like the audio cable for this application. I had a similar issue where my charging cable met my mega fuse. If the crimp is not perfect, or the wire is asked to make a sharp turn, the fine strands are easy to break. After some time these small strands break until you are left with a substantially smaller wire connection and it melts. Happened to me. Good call on the regular automotive cable.

Joe
 
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JD1964

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Jul 14, 2018
#43
  • Jul 14, 2018
  • #43
Put the alt in and rough wired it to do some performance tests. Tests were done at idle 700 with headlights on, AC on max (which makes elec rad fan run) and at different blower speeds.

From low to high blower speeds with AC on max and headlights on at idle here are the numbers. 13.9v, 13.2v, 12.7v, 12.4v.

At idle with AC off and headlights on - 14.3v

Everything on, I mean everything!!!, 2000rpm - 14.1v

No overheating of wiring observed. I'm happy and finalizing cable lengths and connections.
 
Last edited: Jul 14, 2018
Reactions: RangerJoe, RaggedGT, 90sickfox and 1 other person

JD1964

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Jul 15, 2018
#44
  • Jul 15, 2018
  • #44
The alternator is a DB Electrical unit. Got it on Amazon for $78. We’ll see how it holds up. It came with a spec sheet.

https://www.dbelectrical.com/alternators/automotive/ford/mustang/5-0-liter/

 

Blown88GT

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Jul 15, 2018
#45
  • Jul 15, 2018
  • #45
John Dirks Jr said:
...From low to high blower speeds with AC on max and headlights on at idle here are the numbers. 13.9v, 13.2v, 12.7v, 12.4v....
Click to expand...
Looks like the pulley is too big. Pretty common for aftermarket 3G's.
It probably has the 2-1/2" pulley, instead of a 1-7/8"mm pulley.
This one will spin the alternator faster at idle: ASP520004
Scroll to bottom of linked page; http://autospecialties.com/ford.html
 

JD1964

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#46
  • Jul 15, 2018
  • #46
Blown88GT said:
Looks like the pulley is too big. Pretty common for aftermarket 3G's.
It probably has the 2-1/2" pulley, instead of a 1-7/8"mm pulley.
This one will spin the alternator faster at idle: ASP520004
Scroll to bottom of linked page; http://autospecialties.com/ford.html
Click to expand...

The pulley on the old alt was 2 3/4". The pulley on the new alt is 2 3/8". So it's an improvement from before at least. If I'm idling while using AC I'll just turn the blower speed to low. The crank it up when driving again. All good in my opinion. (note > opinion)
 

JD1964

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#47
  • Jul 15, 2018
  • #47
5 pics limit per post so see multiple posts... sorry about sideways pics

I've got it wrapped up I think. Made the cable and trimmed other wiring. Enclosed everything in conduit, taped ends, zip ties. The usual backyard tactics. Its reliable but not gonna win any show car trophy. I wasn't trying anyway. Anyway, pics are everything so here's a few with captions.


Saw this done on YouTube. Made a crimper by cutting a nut in half....here it is



Put the cable in and clamp down with vice


Heres the result. Pretty good huh?


Sweated some solder in for good measure. It sucked up a good amount



Here's the finished cable wrapped in conduit and marked with red electrical tape.
 
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JD1964

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#48
  • Jul 15, 2018
  • #48
Continued from above. There's a third post with more pics too

Here's the cable installed. Its secured to other conduit that runs under the front of the oil pan.


Here's the connection at the alternator


Here's the connections at the fuse holder (125 amp fuse) located on frame near power steering pump.


The original double #10 wires were cut off to reduce excess bundling. I'll keep this section in case its needed in future. The remaining single #10 was capped with a shrink wrap connector so it's available for future use if needed.




Here's the regulator and field wiring wrapped up in conduit.
 
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JD1964

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#49
  • Jul 15, 2018
  • #49

Made another ground cable



Connected ground cable from alternator bracket to passenger side frame




AC gets really cold on medium fan setting. Holds good voltage at idle with AC on, Burrrrrr.......




I love this cig lighter voltage reader. I have several of them and order more to give to friends, I highly recommend you get one. It gives real time running numbers. It's amazing how much movement you get from factory gauges on the foxbody mustangs. I can see how people think they have a problem when looking at the factory gauges. In reality, they are accurate but difficult to get comfortable with. The factory gauges fluctuate substantially, still be in the normal range and give you no clue where you actually are. That goes for voltage, water temp and oil pressure.

Amazon product ASIN B000EVWDU0View: https://www.amazon.com/Innova-3721-Battery-Charging-Monitor/dp/B000EVWDU0/ref=sr_1_2?ie=UTF8&qid=1531714274&sr=8-2&keywords=innova+voltage+tester


 
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Blown88GT

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Jul 16, 2018
#50
  • Jul 16, 2018
  • #50
My voltmeter
 
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