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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

Fuel Purging Fuel System

  • Thread starter Thread starter Window
  • Start date Start date Mar 25, 2018
W

Window

Active Member
Feb 13, 2017
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Mar 25, 2018
#1
  • Mar 25, 2018
  • #1
i want to get the old fuel in my tank out before i run it thru my new injectors, ill attach a pic of my engine how it sits now. i have everything aside from the upper intake and what would attach to it. a few vacuum and coolant lines as well as a couple plugs that would go into the intake and throttle body etc. im wondering if i can just turn the car over so the fuel pump activates for a few seconds like it normally does forcing what fuel is in there thru the lines into a bucket. repeat a couple times with a fresh gallon of gas just to make sure im not running any garbage thru new parts. is this as easy as im making it out to be? any tips would be appreciated.
 
W

Window

Active Member
Feb 13, 2017
111
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Mar 25, 2018
#2
  • Mar 25, 2018
  • #2
i should be more specific. not actually crank the engine just turn the key to the on position so the fuel pump primes.
 

General karthief

wonder how much it would cost to ship you a pair
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#3
  • Mar 25, 2018
  • #3
It will only prime for a few seconds (I think)
@jrichker has a foolproof method using the ole paperclip trick, he will chime in in a little while, I'll look for his writeup in resources
 

jrichker

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#4
  • Mar 25, 2018
  • #4
Pumping out the old gas:

If the old pump still works, you can use it to pump the tank out.

1.) Separate the pressure line (the one with the Schrader valve on it) using the fuel line tools.

Look in the A/C repair section for the fuel line tools. They look like little plastic top hats. You will need the 1/2" & 5/8" ones. The hat shaped section goes on facing the large part of the coupling. Then you press hard on the brim until it forces the sleeve into the coupling and releases the spring. You may need someone to pull on the line while you press on the coupling.







OR








View: https://www.youtube.com/watch?v=vRTjYAxvaCs



Use a piece of garden hose to run from the pressure line to your bucket or gas can. Make sure it is as leak proof as you can make it. Fire and explosion are not part of the repair process...



2.) Jumper the fuel pump test point to ground.







Turn the ignition switch to the Run position. the fuel pump will pump the tank almost dry unless the battery runs down first.



Some 5 gallon paint pails lined with garbage bags are good to hold the gas. The garbage bags provide a clean liner for the pails and keep the loose trash out of the gas so you can reuse it. If you decide to use a siphon, a piece of 1/2" garden hose stuck down the filler neck will siphon all but a gallon or so of the gas.
 

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  • Fuel pump test jumper 86-93 Mustang 60%.gif
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Last edited: Mar 25, 2018
W

Window

Active Member
Feb 13, 2017
111
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Mar 26, 2018
#5
  • Mar 26, 2018
  • #5
Alright will do this. As the car sits now it will be safe to apply power to stimulate the fuel pump?
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,892
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203
polk county florida
Mar 26, 2018
#6
  • Mar 26, 2018
  • #6
Yes
 
W

Window

Active Member
Feb 13, 2017
111
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Mar 26, 2018
#7
  • Mar 26, 2018
  • #7
Awesome thanks for your guys' help once again.
 
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