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

carbed fuel problem

  • Thread starter Thread starter slystang
  • Start date Start date Jan 5, 2004

slystang

Founding Member
Jul 3, 1999
759
0
0
horseheads, Ny usa
Jan 5, 2004
#1
  • Jan 5, 2004
  • #1
I've got a summit racing electric pump and spring type regulator. My fuel pressure won't stay consistent. right now I've got the line from the pump running into the bottom of the regulator, and a line running into my carb from one of the side ports on the regulator. The other side outlet is plugged. My pressure will stay around 7 pounds but occasionally spikes to about 25 psi. then gas usually ends up spilling out of the top of my carb and all over my engine. So as you can probably see I have a problem. Do I have a problem with how my regulators set up? Do I need to run a return line?
 

slystang

Founding Member
Jul 3, 1999
759
0
0
horseheads, Ny usa
Jan 5, 2004
#2
  • Jan 5, 2004
  • #2
who else out there has a fuel setup like mine. I've been told that every fuel system needs a return. I was gonna buy the Aeromotive fuel pump controller that adjusts voltage to the pump based on RPM. But I don't know if that would actually solve my problem.
 

slystang

Founding Member
Jul 3, 1999
759
0
0
horseheads, Ny usa
Jan 6, 2004
#3
  • Jan 6, 2004
  • #3
I can see I'll get no help from here. Guess I'll just run a return line and see how it works.
 
J

jerry beach

Founding Member
May 20, 2002
2,671
0
46
Ocala,FL
Jan 6, 2004
#4
  • Jan 6, 2004
  • #4
All fuel systems dont have return lines. I dont know if you need one or not, but I dont see it solving your trouble. I would return the regulator. It is not working properly. If you get a reg that works, you should be ok.
 
W

wildstang347

New Member
Jan 2, 2004
83
0
0
Jan 8, 2004
#5
  • Jan 8, 2004
  • #5
hey sly if the electric in tank fuel pump was used, u do need a return style regulator to bleed of fuel pressure. fuel injected motors run at much higher fuel pressures requireing a return line, if not u will definitely experience what you are! i made a similar swap as you did but scrapped the in tank pump for and external pump do to my setup demands. but you can run an intake pump and order the correct regulator from jegs or summit. i was gonna go that route but went the external way replaceing pump assembly with the 3/8 diameter kit deleteing the pump in the tank in order to feed my motor more fuel for produceing in excess of 400hp
 

thegabrielles

Member
Feb 26, 2003
516
1
16
Atlanta Georgia
Jan 8, 2004
#6
  • Jan 8, 2004
  • #6
I have the same set up on my 82, with no return line. It will cause the fuel pump to run a little noisier but will be fine. I am running 7.5lbs to my carb and have had no problems. I have a second line coming off the regulator going for a gauge. I am running a Mallory Pump and a Holley regulator, I had a Holley Blue Pump but had problems with it right out of the box.
 

slystang

Founding Member
Jul 3, 1999
759
0
0
horseheads, Ny usa
Jan 8, 2004
#7
  • Jan 8, 2004
  • #7
Ive got a summit racing high volume external pump. The kind summit sells with a complete fuel system kit. I think the regulator alone costs like $13 from summit. Should I just get a new regulator? Maybe an Aeromotive one? Thanks for the input guys. It's good to hear some opinions aside from my own. It's good not to blow money on unnescesary parts too.
 

ashford

Member
Dec 19, 2003
485
0
16
fargo ND
Jan 8, 2004
#8
  • Jan 8, 2004
  • #8
that pump has too much power to be dead headed into an inline spring regulator. you can "t" off the output of the pump back into the inlet side through an orfice, but may have some delivery problems at high demand. id rather just get the recomended regulator
 

12sec67

Active Member
Oct 6, 2003
1,301
1
36
San Diego, Ca
Jan 8, 2004
#9
  • Jan 8, 2004
  • #9
what psi does the fuel pump push. a regular regulator will not hold back alot of psi.
 

thegabrielles

Member
Feb 26, 2003
516
1
16
Atlanta Georgia
Jan 9, 2004
#10
  • Jan 9, 2004
  • #10
My Pump is a 14psi pump regulated down to 7.5 with no problems. The regulator should not have to much problem with that drop. Seems like you have a regulator problem, maybe it just is not good enough for the pump pressure you have. Make sure your regulator will support your pump. With the spikes you are getting it sounds like the spring is just not handling the pressure.
 
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