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  • Fox 5.0 Mustang Tech

DASH WIRING AND FUEL PUMP

  • Thread starter Thread starter SCORPIO72
  • Start date Start date Sep 15, 2009

SCORPIO72

New Member
Aug 29, 2009
16
0
0
ILLINOIS
Sep 15, 2009
#1
  • Sep 15, 2009
  • #1
Have two questions here.....


First off i am going carb on my 5.0. I have took out all the EFI wiring. Just for knowledge. what is the wires for on the 8 pin green connector located by where the ecm used to be? and will i have to utilize any of these for my carb conversion? i have read many wiring diagrams and cant figure them out. Thers is...

on one side
red
br/g
empty
big gy/y

other side
br
r/lg
bk/w
o/bl


My other question is. I know i have to use low pressure fuel pump, but can do so and leave the existing one in the tank(cutting all power to it of course)? I was told i could by one and told no by another, little confused here.
 

liljoe07

5 Year Member
Feb 18, 2009
1,622
363
124
Cartersville,Ga
Sep 16, 2009
#2
  • Sep 16, 2009
  • #2
Green connector 39 contains the PINs for the VSS, HEGO power, the Fuel Pump Monitor and Power, CEL, Low oil level sender, and AC on power coming from the dash.
 

jrichker

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Mar 10, 2000
27,512
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Dublin GA
Sep 16, 2009
#3
  • Sep 16, 2009
  • #3
If you try to use your current tank, you will need to pull the fuel pump out and fabricate a pickup tube & strainer sock to replace the fuel pump. The external pump will not suck enough fuel through the EFI pump to provide good performance.

Or you can have a sump fabricated and welded onto you existing tank. Many welding shops will not weld fuel tanks because of the dangers involved if the tank isn't purged properly.

You will need an external electric fuel pump unless you change the timing cover for one with the mechanical fuel pump mount on it. Rip all the EFI wiring out, and the computer controlled fuel pump won't work. You will need to add a relay & switch and wire in the existing inertia switch for an external low pressure electric fuel pump. Do not try to wire the fuel pump without the relay. The 15-20 amps the pump pulls will overload the circuit. This will take power away from other items on the same circuit or cause the fuse or fuse link to blow.



You will need to run some new fuel feed lines or braided hose. The 3/8" aluminum tubing works well, but you will need a flaring tool and bending springs to fabricate the lines. Braided hose is easy to run and route, but is much more expensive. It is about $3.50-$4.00 a foot plus the end fittings, which are $3-$4 each. Fabricating hose assembles can be difficult, but anyplace that makes hydraulic hoses can do it for you for an extra charge. See Amazon Hose - Rubber, Hydraulic and Industrial Hose - since 1919 for more information.

For stainless steel braided hose and fittings for automotive use:

See Search Results for stainless - SummitRacing.com

stainless steel hose - JEGS High Performance

See Eaton's Aeroquip Products for more information on High performance automotive hose products

The fancy red & blue AN fittings require a 37 degree flaring tool. A standard automotive or household plumbing tool is 45 degrees and cannot be used with AN flare fittings. If you do, the flare is subjected to too much stress when the fitting is tightened, and is likely to fail or leak.

See Industrial Supply Equipment from MSC Industrial Supply , McMaster-Carr or for the flaring tool you will need . Prices start at $81 and go up

Browse the MSC Big Book


McMaster-Carr




Chilton's wiring diagrams

Gale Cengage Product Failure
How to solder like a pro - Ford Fuel Injection How To Solder Like a Pro a must read for any automotive wiring job.

Soldering pigtails onto existing pins is road kill quality work as far as I am concerned. Take some time to study the way the Ford connectors are assembled and you will find that a small jeweler’s screwdriver will release the pins from the connector shell. New pins and a crimping tool are available from the Standard Motor Parts or Bendix Electrical parts line that the NAPA & Bumper to Bumper Auto Parts stores carry. Ask any auto parts store about Standard Motor Products or Bendix Electrical wiring parts. Those that carry them will be able to get the parts you need. AutoZone has a cheap kit with 10 pins for about $5. Just enough pins to leave you short when assembling a connector.
 

86turbo

Member
Apr 8, 2006
183
0
17
Sep 17, 2009
#4
  • Sep 17, 2009
  • #4
just go find a tank from some old carbed 4 banger fox and save yourself the headache
 
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