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Any tips for fuel pump replacement

  • Thread starter Thread starter russ1979
  • Start date Start date Apr 2, 2009

russ1979

Member
Oct 6, 2006
152
0
16
albuquerque, new mexico
Apr 2, 2009
#1
  • Apr 2, 2009
  • #1
i'm going to be swaping out my stock fual pump today for the bbk 255lph pump.

does anybody have any tips or tricks or things i might need to know?
thanks guys
 

kpack5982

Yeah, it was pretty stiff, but eventually a buddy
Jul 13, 2005
325
1
19
Granger, IA
Apr 2, 2009
#2
  • Apr 2, 2009
  • #2
ah boy are you in luck, I just did mine 2 weeks ago. It took me and a buddy like 4 hours to do it. Neither of us had done it before.

Take out the fuel filter.

Take out the bolts inside the gas fill and there are also 4 on the backside of that underneath the car.

Loosen the bolts to the straps holding the tank up.

Jack up a 2x4 under the tank to help balance it.

Take out the bolts for the straps and slowly lower the tank, slowly pulling the filler neck out of the tank as you drop it, you may have to work it a little.

Continue lowering tank all the way to the ground, (don't worry about the fuel lines, there is plenty of leeway there for teh lines)

Once on the ground disconnect the fuel lines from the 90degree lines coming from the tank, one is a clip like the fuel filter lines and the other requires a disconnect tool or small screwdriver to push the tabs out.

Use a punch to hit the outter ring counter clockwise to release the locking ring.

Then pull the bastard out! That may take some finessing too.
 

jrichker

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#3
  • Apr 2, 2009
  • #3
Here are some useful tips...

I have done the tank removal three times, and the main issues are getting the car up on jack stands and getting the gas
out of the tank. DO NOT try to do this job without jack stands. Becoming a pancake is not part of the repair process.

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.



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.

Remove the filler neck bolts and put them in a zip bag. Disconnect the supply & return lines by removing the plastic clips
from the metal tubing. If you damage the clips, you can get new ones form the auto part store for just a few dollars.
I have used tie-wraps, but that is not the best choice. Then you remove the two 9/16" nuts that hold the T bolts to the
straps. Put the nuts in the zip bag with the filler bolts. Pull the plastic shield down and away from the tank.
Once the tank drops a little bit you can disconnect the wiring for the pump & fuel quantity sender.

The pump and fuel gauge sender assemblies comes out by removing a large metal ring that unscrews from the tank.
There is a separate mounting/access plate for the fuel pump and fuel gage. You are supposed to use a brass punch to tap
on the ring so that you don't make sparks. Look closely at the rubber O ring gasket when you remove the fuel pump or
sender. The pump assembly requires some twisting and turning to get it out the hole.

Look very closely at the electrical wiring. The stock fuel pump wiring can overheat and melt the insulation. Mine had some
really crummy plastic tubing slid over the quick disconnects. If the wires ever got together, there would be sparks inside the
fuel tank and no more Mustang. I eliminated the splice in the middle of the wiring and went straight from the pump to the
feed through connectors for the wiring. It required some soldering and crimping of new tabs on the wires, but it made a
neater job.

Inspect the pump mount to metal tubing bracket. Mine broke and I couldn't get it to solder back together. I drilled a small
hole for a machine screw & self locking nut to hold the clamp and bracket together.

The pump is easy to get off the mount but is somewhat difficult to get back it the tank without damaging the sock filter or
tearing it on the tank baffle. When you install the metal ring that holds the pump in place, watch out for the gasket O ring.
Some RTV may be helpful if the ring is not in excellent condition.

The tank to filler pipe seal is a large rubber grommet. Inspect it for hardening, tears and damage. At $20 from the Ford
dealer, it might be a good idea to replace it.

I used a floor jack to help lift the tank back in place. You may find that it is the only time you really can make good use of a helper.
 

85_SS_302_Coupe

it sucks (I know) to be on the receiving end
15 Year Member
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Northern KY
Apr 2, 2009
#4
  • Apr 2, 2009
  • #4
You know, this is sort of ghetto, but a buddy of mine just cut a hole in the floor of his trunk to get to the pump. Then he took the metal "flap" he cut out and cut it completely off and cleaned up the hole and made a door that covered the hole with a hinge and a rubber seal.
 

2000xp8

SN Certified Technician
Aug 8, 2003
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Apr 2, 2009
#5
  • Apr 2, 2009
  • #5
85_SS_302_Coupe said:
You know, this is sort of ghetto, but a buddy of mine just cut a hole in the floor of his trunk to get to the pump. Then he took the metal "flap" he cut out and cut it completely off and cleaned up the hole and made a door that covered the hole with a hinge and a rubber seal.
Click to expand...

Not really a ghetto idea.
I believe there is actually a kit to do in car pump changes.


Honestly, a fuel pump change shouldn't take more than an hour.
2 bolts on the straps
I have always taken the intake tube bolts so it hangs, may not be necessary, but only takes a minute.
Drop the tank, replace pump, then reverse the process.

Most important thing, is to run the car nearly out of gas. Makes life much much easier.
 

ShortThrow50

Member
Oct 22, 2006
923
2
16
Pa
Apr 3, 2009
#6
  • Apr 3, 2009
  • #6
Yeah I agree. My first and second time took no more than an hour. It's only a couple bolts that are easily accesible
 
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