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How to change your fuel pump.

92896 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 have had fuel pump troubles for a long time, so there is a hole cut in the floor. I'm about to change my pump, as soon as it gets here, should be here tomorrow or Wednesday. Until then, I sit here and eat fudge. :thumbup:
I can cut a hole, no problem. Probably not as nice as some i have seen on here. Their are a lot of real crafstman on here. The problem is where to start the hole. The close up shots are nice but what are the measurements for the hole? I guess I will just do a few polit holes first, check and see if my van has the steel plate over the tank...
Drilled a small pilot hole over the pump. I hit that steel plate. I thought for a second of really laying into the floor and plate but dropped the tank instead. It was a pain, mostly because of all the rust and debris that falls into my eyes, and the smell of gas.
this is my parts van. took the fuel pump out today and put in into my next van, which fixed the problem on this thread = viewtopic.php?f=43&t=15928" onclick=";return false;

i didn't expect the second cover under the floor, that wasn't there on my 2003 astro.








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That second cover just sits there; it protects the top of the pump and the fuel line connections.
HAHAHA I just saw the change too! :rofl:
Found Coinage...

:rofl: :rofl: :rofl: :rofl: :rofl:

That has to be enough money there for a new fuel pump! :rockon:
OK I flubbed. Dropping my tank I REMOVED (not just loosened) the strap hanger bolts on the driver side. They came out fine. I did what I had to do. Now re-installing them, the front one went in just fine. But the rear one seems like it's spinning the nut that's up in the frame member. I assume there's some kind of welded nut up there. Mine has apparently broken loose and now free spins with the bolt.

I'm thinkin' a solution might be to hacksaw off the bolt head, then use a nut in it's place to cinch up the strap. Not looking forward to hacksawing the darn thing under there, upside down etc. Don't want to risk an electric cutoff wheel for the sparks+gas proximity thing.

Any brilliant ideas from you brilliant idea-meisters?

Can I somehow get that nut up in the frame to sit still while I tighten up the bolt?

RECox286 has a solution here: and replace with square nut? That is if you can get the old one out and new one in.

Similar to this video

The bolts came out fine on mine (lots of penetrating spray) but one going back in was really tight and was worried about the nut breaking loose. It wasn't cross-threaded so I just kept spraying it with penetrating oil and working it in slowly. I could have chased the threads with a tap but didn't have my set onsite.
I resolved it with no grief. Just tightened up that "middle nut" to lock up the upper half. The strap was apparently tight enough to hold things.

Drove to the smog station for the FOURTH time in two days, and...passed.

An 8 inch piece of hose ABOVE the fuel tank was cracked enough to not pass the vapor pressure test. So I learned how to drop a tank. My fuel pump is new (year old Delphi) so I'm sure I've got some time left before that needs replacing again.

Not to highjack, but is the fuel pump damper a required piece during new pump installs? It seems like a weak link pron to leaks and would be better being replaced with a slice of fuel line..

Whats its purpose anyways?

I'm seriously thinking about doing the cut out so I can access from within the van..

I think it is to stable the fuel. I don't think it is necessary. Some people just put a line in instead.
This is great info. I wish I had found it BEFORE I paid $400 to have my FP replaced at a shop.

On that, ever since my pump, etc., was replaced, my fuel gauge has been whacked. It acts really sensitive for the upper end or the range, but then takes forever (I am guessing) for the lower range. The reason I say I am guessing is because I don't have the nerve to see how far I can go before running out. After I noticed this, I took my van back to the shop and had them check to ensure that the correct pump had been installed. They assured me that it had (like they would say otherwise!) and sent me on my way. Has anyone else seen this? What causes it? I believe I have a 27 gallon tank. Is there another pump/sending unit that fits these vans?

I like the idea of cutting a hole in the floor to access the pump. Where should the hole be cut? Thanks!
what a great thread - thanx for the pics - have downloaded them - all one needs to do is see the ribs of the floor in the pics and where others have cut. I use a saw zaw often as an electrician and I thought, after cutting the hole, I could line the sides of the hole with some strong thick sheet metal strips. Then just 4 - half inch self tapper screws to hold the access plate, so cut all four sides to your access hole, then screw it down to the strips.... this way, you're not fighting any 3 sided metal access plate by trying to bend it down and out of shape - you also have almost as strong of a floor as before with no part of the 3 sided access plate hang ups - when time comes to need access again, just unscrew your access plate.
You could also seal it with some silicone for water/air proffing it.... :D

JUST MAKE SURE you cut just 3 sides of your carpet, so you can just role it over the access when you're one - duh, ok
So here is the start of cutting it open. I just took some pics from above and went by the floor lips for the right place to mark and cut.




here is where I had to be super careful not to cut intothe lines or wires..... gotta be really good with a sawzaw, otherwise, you'll make a big oops - I used a screw driver to pry up on the metal to avoid cutting at the vunerble places


it was nice to get her good n clean.
Notice below, the two metal strips for the hatch plate support - cost a buck each at home depot (in the lumber fittings section) and some 1/2" self tapper screws to hold the metal sides pieces. they we the 12 long pieces


after dropping the cover back on, those 2 side supports were very strong. no need to screw the cover plate on, just fold the rug back and walla, piece of mind for when the fuel pump needs replaced.

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Well, it paid off! After 2 years from posting the pics above, my fuel pump Kick the bucket and I had to replace it just yesterday. :D
I did mine the old fashioned way and would never do it again...about lit myself on fire. My autozone pump is working fine and the fuel gauge is just a bit finicky when totally full.

Dropping the tank is for the birds!
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