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How to change your fuel pump.

92894 Views 131 Replies 69 Participants Last post by  JesusOnSkates
This write up was done while I removed and installed my new fuel pump.

Step 1. Disconnect the negative (-) battery cable.

Step 2. Raise and SAFELY support your van with either jack stands or ramps. The higher the better, also note that it does help to raise both the front and the rear of the van.

Step 3. I reccomend that you drain the fuel from the tank unless you have a quarter or less. This can be accomplished with a hand siphon or pump.

Step 4. Remove the splash gaurd from the driveshaft side of the fuel tank. It is installed with four press in clips and multiple slip on clips. It looks like this.
Step 5. You will need to loosen the fill hose attached on the drivers side of the tank. There are two clamps on this hose. It looks like this.
Step 6. It makes it easier to disconnect the fill hose if you remove the retaining screws that hold the fill hose in place inside the fuel door.
Step 7. Break loose but DO NOT remove the drivers side retaining strap bolts, on most vans the bolts do not need to be loosened as they are set from the factory to allow the strap to rotate freely once the bolts on the opposite side are removed, mine were over tightened by the previous owner or their mechanic. There is a hidden 15 mm nut on top of the strap where it attaches to the chassis. I have a needle nose vise grip on it in this pic to show where it is. I used a 12" extension and 15mm socket and a 15mm wrench to loosen these.
Step 8. Break loose the driveshaft side retaining strap bolts but dont remove them yet.
Step 9. Now is the time to support the fuel tank. I reccomend the use of either a transmission jack or a atv/motorcycle jack for this as it greatly eases the process.

Step 10. The fuel lines and the vent lines should now be removed from the hard lines. the two fuel lines require the use of a 5/8 line wrench and a 3/4 line wrench. the two vents are simple pinch clamps that can be removed with a pliers. Removing the rubber lines for the vents is a bit easier if the tank is lowered a few inches.

Step 11. Now it's time to remove the wiring harness. The wires run across the top of the tank and over to the drivers side they then follow the "frame" rail forwards and are attached to the body near the transmission. Unplug the harness and remove it from its retaining clips. Once it is free from the clips feed it through the hole in the "frame" and set it off to the side.

Step 12. Remove only the driveshaft side strap retaining bolts and then turn the straps 180 degrees out of the way.

Step 13. Now slowly lower the fuel tank being careful to make sure nothing gets caught and causes the tank to fall.

Step 14. Now it is time to remove the fuel pump / sending unit assembly. I accomplished this with a brass drift punch. Use the punch and a hammer to rotate the lock ring counter clock wise until it lines up with the notches in the top of the tank.

Step 15. Next you will need to remove the assembly from the tank be careful with this so the strainer does not fall off in the tank and the float arm does not get damaged.

Step 16. To remove the fuel pump from the sending unit you will need to remove the wiring harness and then push the pump up towards the top of the unit and when you have clearance tilt the fuel pump outwards and then pull down on it to remove it.

Step 17. Replace the o-ring seal on the top of the tank with a new one.
Step 18. Installation is the reverse of removal.

I hope this helps someone out there with there fuel pump job. Feel free to make comments on this post so I can make sure my details are as accurate as possible.
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More evidence that the only pump to put in is AC Delco/Delphi.
It's not that hard. The bolts one side of the straps just need to be loosened slightly, then the bolts on the other side removed. I have a floor jack I put underneath with a 2 foot 4x4 chunk of wood to balance the tank on while I slowly let it down enough to get my hands in there to disconnect the fuel lines (which is easiest through the driver's side rear wheel well on my Bravada, but I'm not sure on the Astro) and the filler hose. Then you can let it down all the way.

You'll need a brass drift or sacrificial screwdriver to get the lock ring loose. I'd spray it with PB Blaster first, then pound gently on one end, then the other to break it loose, then drive it to where you can remove it.

Pull the old pump out carefully, getting the float out with it, then put in the new pump just as gently. Reinstallation is the reverse of removal.

I have a couple pics of when I lowered mine a couple inches to check the fuel tank pressure sensor somewhere in my Pics of the New '99 Safari thread in the General forum.

Don't forget to replace the fuel filter at the same time.
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That second cover just sits there; it protects the top of the pump and the fuel line connections.
Some vans have a cover over the fuel pump, hoses and tank. My '99 does, my '02 does not. Haven't looked at the '00s tank yet.

It seems to be hit or miss, so you have to see for yourself.
You'll be fine with 4 gals.

Just please disconnect the battery.
I honestly don't understand why anyone cuts a hole. It takes so little time to drop the tank and you haven't opened a hole in the floor of your van that will allow exhaust into the van and create a potential rust spot on your van, I just don't get it.

Plus, while you've got the tank down, you can get to the brake and fuel lines next to the tank to clean 'em up, put rust reformer stuff on them of needed and paint if they don't and on the van around the tank, hopefully making that stuff last a little longer.
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