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1964.5 Wiring Help Needed...

  • Thread starter Thread starter Midnight Express66
  • Start date Start date Aug 6, 2014

Midnight Express66

New Member
Jul 8, 2012
7
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1
Hastings, Minnesota
Aug 6, 2014
#1
  • Aug 6, 2014
  • #1
Hoping someone with a 1964.5 or a better schematic than I can find can help me.
I'm putting in new underhood harnesses in my pops 64.5/early 65 Mustang as most of the wiring in the car has been hacked together.

On the regulator side of the generator harness there is a yellow smaller wire and larger black wire with a yellow stripe on the same terminal clip. The terminal looks like the fork type on the other wires that attach to the voltage regulator. This fork terminal with the two wires (yellow and larger black with yellow stripe) was wrapped and electrical taped around a larger black wire with C-4ZB-15A669-A SX FOMOCO that runs up to and through the firewall up and over from where the gauge feed harness plugs into the firewall.
I'm wondering where the proper location for these wires are or their function. I doubt Ford would be jimmying up electrical connections like that.
I've been battling electrical gremlins for sometime now, moving forward with all new harnesses.
Don't know if it helps but the engine is a 289, the car is an early 65/64.5 convertible generator car with the exposed terminal voltage regulator. Previous owner also hacked in what appears to be a '66 five dial gauge cluster.

Installing new underdash harness and possibly return to the sweep speedo if I can find one is the next headache, I mean project.
 
B

barnett468

Active Member
Aug 1, 2014
179
24
28
Aug 7, 2014
#2
  • Aug 7, 2014
  • #2
Midnight Express66 said:
Hoping someone with a 1964.5 or a better schematic than I can find can help me.
I'm putting in new underhood harnesses in my pops 64.5/early 65 Mustang as most of the wiring in the car has been hacked together.

On the regulator side of the generator harness there is a yellow smaller wire and larger black wire with a yellow stripe on the same terminal clip. The terminal looks like the fork type on the other wires that attach to the voltage regulator. This fork terminal with the two wires (yellow and larger black with yellow stripe) was wrapped and electrical taped around a larger black wire with C-4ZB-15A669-A SX FOMOCO that runs up to and through the firewall up and over from where the gauge feed harness plugs into the firewall.
I'm wondering where the proper location for these wires are or their function. I doubt Ford would be jimmying up electrical connections like that.
I've been battling electrical gremlins for sometime now, moving forward with all new harnesses.
Don't know if it helps but the engine is a 289, the car is an early 65/64.5 convertible generator car with the exposed terminal voltage regulator. Previous owner also hacked in what appears to be a '66 five dial gauge cluster.

Installing new underdash harness and possibly return to the sweep speedo if I can find one is the next headache, I mean project.
Click to expand...


the fork goes on the end of the regulator

the big yellow/black wire goes to the generator

the thin yellow/black goes to the connector at the firewall and into the car to the generator indicator lite

http://www.midlife66.com/wiring/wiring.html
 

Midnight Express66

New Member
Jul 8, 2012
7
0
1
Hastings, Minnesota
Aug 8, 2014
#3
  • Aug 8, 2014
  • #3
barnett468 said:
the fork goes on the end of the regulator

the big yellow/black wire goes to the generator

the thin yellow/black goes to the connector at the firewall and into the car to the generator indicator lite

http://www.midlife66.com/wiring/wiring.html
Click to expand...

Okay, so after looking at that diagram I think its home is the BAT terminal on the volt regulator. Hopefully there's an early Mustang or Falcon at tomorrows cruise in that I can snoop around and see.

Before I hook it up and put the battery back in I'm hoping to see another car in person, I'd hate to fry the expensive reproduction regulator I put in. It must not be too important because the car has been running fine for the 30 years my fathers owned it with it taped to whatever that big black wire is.
Pops guessed maybe convertible top power since my '66 coupe doesn't have that wire but the wiring between my '66 and his '64 is very different.

Anybody have a way to run the part number on the mystery black wire? printed 4ZB-15A669-A SX FOMOCO I'm going to attempting tracing it behind the dash after work tomorrow. Thank you for your help so far!
 
B

barnett468

Active Member
Aug 1, 2014
179
24
28
Aug 9, 2014
#4
  • Aug 9, 2014
  • #4
Midnight Express66 said:
Okay, so after looking at that diagram I think its home is the BAT terminal on the volt regulator. Hopefully there's an early Mustang or Falcon at tomorrows cruise in that I can snoop around and see.

Before I hook it up and put the battery back in I'm hoping to see another car in person, I'd hate to fry the expensive reproduction regulator I put in. It must not be too important because the car has been running fine for the 30 years my fathers owned it with it taped to whatever that big black wire is.
Pops guessed maybe convertible top power since my '66 coupe doesn't have that wire but the wiring between my '66 and his '64 is very different.

Anybody have a way to run the part number on the mystery black wire? printed 4ZB-15A669-A SX FOMOCO I'm going to attempting tracing it behind the dash after work tomorrow. Thank you for your help so far!
Click to expand...
hello;

ok i have no idea what you are talking about. the wiring diagram is correct. do NOT add any wires to the regulator.

if it has a power top the wire goes from the front power post on the solenoid to a relay by the solenoid then to the top.
.
 

Midnight Express66

New Member
Jul 8, 2012
7
0
1
Hastings, Minnesota
Aug 10, 2014
#5
  • Aug 10, 2014
  • #5
barnett468 said:
hello;

ok i have no idea what you are talking about. the wiring diagram is correct. do NOT add any wires to the regulator.

if it has a power top the wire goes from the front power post on the solenoid to a relay by the solenoid then to the top.
.
Click to expand...


Last night I found an unrestored 64.5 Mustang coupe 260 3spd that was in great shape. I didn't catch the owners name but he was nice enough to let me comb it over closely and even snap some reminder pictures.

The yellow and black/yellow stripe wire in question on the new harness goes to the BAT terminal on the voltage regulator. The mystery black wire I think is the power top, and is supposed to go to a relay/resistor thing on the ignition solenoid as you had mentioned. I'm missing the square two post relay/resistor thing and the clip that attaches it to the solenoid and the wire.

I'm going to trace the black wire under the dash to make sure it is for the power top like I think. The car I looked at was a coupe and there was a dimple where that wire goes through the firewall on my pops car so I think it must be a convertible thing.

Also found out there is a nifty plastic gaurd clip that covers the voltage regulator terminals. Found a NOS one on Ebay. It was very helpful to look at a very nice original.
 

Midnight Express66

New Member
Jul 8, 2012
7
0
1
Hastings, Minnesota
Aug 13, 2014
#6
  • Aug 13, 2014
  • #6
The mystery black wire is indeed the power feed for the power top, I've ordered a new underhood power feed wire because the wire was cut and missing the terminal. Also ordered a new circuit breaker and the clip to attach the circuit breaker to the positive side of the ignition solenoid. On to the next project! Thanks for your help!

I'm still on the look out for an early '65/64.5 D code 289 (5 Bolt bell housing, oil fill on the timing cover, 4V,) its the motor code in the cars vin number, a later model 289 is in the car now. I would like to find the earlier motor and bell housing, not overly concerned with the date, but a fairly complete early 289 D code is what I'm after.

Pops car was the 417th Mustang built in the San Jose plant. D code 289, four speed, 9" rear, convertible, originally Dynasty Green, its currently Wimbledon White.
 
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