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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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I need to do this now too on my 89, and id like to 2nd or 3rd the request for pump access hole pics! We need pics!
I just had my FPump changed by a certified mechanic, Delphi pump and strainer.
Cost was $305 parts and labor. Worth it to me for the hassle and work involved
dropping the tank or cutting the floor.

tinworm said:
I need to do this now too on my 89, and id like to 2nd or 3rd the request for pump access hole pics! We need pics!
Ok, for those of you who have shorty vans, if they are like my 89, the exact center of the fuel pump is located 10 and 1/4 inches to the passenger side of the second driver side middle seat bracket on the floor, and 3 inches back. If you measure that far over, and that far back, mark, and then cut around you should be right above the pump. I just opened a HUGE hole in the floor of my van, leaving nothing to chance :mrgreen: In for a penny, in for a pound

EDIT- Done. Less than an hour to complete the job going with the hole in the floor method. IMO, having changed a lot of fuel pumps, this is the way to go. Now to come up with a nice looking hatch.
Okay, over the weekend the wife and I where GOING o take the grand daughter home from our place in Oklahoma City to meet her mother in Denver Colorado, we got as far as Hays Kansas, stopped for dinner and when we returned to the van after dinner, it cranked nice and strong but no fire. I took the dog house off, removed the air filter and cranked again, NO FUEL showing at the injectors, so I sprayed some starter fluid in the throttle body and it started right up and ran as long as I was spraying starter fluid. This told me it was more than likely a fuel pump. We got the grand daughter home to Denver by calling my sister to come get her, and called my best friend to drive up from Dallas with tow dolly to get us home. I have read this post a few times, to get a good idea what to do, and am ready to go start the process of replacing my FP. I purchased a BOSCH pump, as it was all I could afford, does any one know if these are good pumps ? I know as a general rule, BOSCH is a good brand, but how are the FPs?

Thanks and wish me luck ! :bow:

EDIT: My van is a 1992 CS with a Z Code (TBI motor), does this change anything ?
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My '95 Astro died yesterday.
The sound of the pump, initiating when you turn on the ignition, has changed over a few days, from a lite humming, to a darker growl. And yesterday, the engine just stopped.
I managed to crank it up again, and somehow got to where I was going. And with a few stops today, we got home again in one piece.
So I will have to change the fuel pump as well.
Thanks to all on the tread. Would be nice with some pics, yes. I changed FP on a Taurus I had once. Maybe the same? Don't think I'm gonna make hole in floor.( carpet and all)
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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nu85 said:
Uh oh...I bought an autozone fuel pump. Whats wrong with them?
The off brands, non ACDelco or Delphi, just don't seem to last from what we've seen here. Don't let your tank get below 1/4, the fuel cools the pump so that helps the life of any in tank pump.
Thanks for input, Leeann. will check out your pics. Lowering the tank, you can se the shape of the underbody it's covering.
Hey nu85, is your van fuel injected or carb'd?

The FI uses the in tank pump.
It looks like the carb engine has an engine block mount, cam or crank driven pump.
At least that's what I think I see when I try and look up the part for an 85.

I made a hatch. see pics on" what have you done.. thread
astroknut said:
I made a hatch. see pics on" what have you done.. thread
Just checked out the pics in this thread. Very nice, they are a big help. I plan on going this route to change my pump tomorrow, however i will be using a sawsall to cut the hatch door. I'd imagine from the look of the pics i will need a shiv of some sort to keep from cutting too deep. How deep can i go without cutting through the wiring, etc.?
Here's some more info regarding cutting a hole in the floor to get access to the fuel pump

My van is a '94 with two single seats in the second row, which places a seat anchor close to the area to be cut. See maroon photo. There is no such issue with the single bench seat configuration, see blue photo.

A word of caution to those contemplating using a powered saw to open the hole: the fuel lines are close to the floor! As you can note from the maroon photo, I knicked one of lines even though I was using an air chisel that didn't extend very far down. In any case, it is better to make just three cuts and fold the piece up on the fuel line side (right side looking forward).

The best tool to use would be a pneumatic air nibbler. I had too much air pressure on the chisel and made a messy job.

This project started out as a "get ready" precaution for the day my fuel pump quits(present milage 194K). However, as is obvious, there was considerable corrosion that needed to be dealt with in any case.


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I am seriously considering doing this cut now before the inevitable happens so that I am prepared.

And the only reason why I am reluctant to just change the pump the "normal" way is because even new pumps can fail while the OE unit runs indefinitely. I am kind of torn between leaving well enough alone and doing the preventative work.
Couple pics of my fuel pump hole:

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cut a hole in the floor ! it's the easiest and fastest thing to do !
Hello, I'm in the process of changing out the pump on my 99 Astro, in general I've followed the steps outlined in this thread ... which has been helpful.

Here are some pictures, my 99 differs a little bit from the pictures posted so far.

A metal plate covers the assembly, which will make it harder for someone wanting to cut through the floor for access:

Three lines attach to the assembly with push on plastic lines and connectors:

There isn't a lock ring to tap out. It's held in place with a inner snap ring. The plastic lines are different so I marked them to keep the order straight. Shown is the OEM Delco pump which lasted 13 years:

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The tip about the hanger straps was very helpful. I had an Airtex pump on hand so I put that one in. So far so good. We will see what happens. Thinking about getting an ACDELCO or Delphi to keep on hand.
Too much info is never a bad thing... here's a pic of my recent fuel pump replacement - GenIII 27 gallon plastic tank with new Delphi pump assembly installed. You can see the evap canister, hoses and solenoid which need to be disconnected as well.

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How long should this job take?
Dropping the tank............set aside a Saturday or Sunday to do it.

Cutting the floor and doing it....2 hours. :rockon:
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