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I spoke too soon in another post - the 94 FWB wasn't as well sorted as we thought. The fuel pump has died and the car's in a parking lot. Here's the question - is it possible to drop the tank and swap the pump with all four wheels on the ground and not elevated?
 

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I spoke too soon in another post - the 94 FWB wasn't as well sorted as we thought. The fuel pump has died and the car's in a parking lot. Here's the question - is it possible to drop the tank and swap the pump with all four wheels on the ground and not elevated?
no....unless you cut (carefully) a trap door to access pump from up top

you can try smacking the forward DS of the tank with a BFH to see if it "wakes up" the fuel pump to get the car somewhere you can work on it
 

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no....unless you cut (carefully) a trap door to access pump from up top

you can try smacking the forward DS of the tank with a BFH to see if it "wakes up" the fuel pump to get the car somewhere you can work on it
Hm. Okay, thanks. By the way, does this design have a hose between the pump and a pickup point like some designs do? It had been acting like it was running out of gas at 1/8th tank a couple times on recent journeys, though it did 200 mile runs just fine reportedly.
 

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The pump has a small rectangle filter that attaches to bottom of pump. Both sit right off the bottom of the tank within a baffled area...not a pump up high with a hose/tube running to the lowest point in tank

The pump sits inside the whole sending/float assembly. You remove that and then remove the pump from within the assembly...or just buy a whole new assembly

Have to drop tank and ideally you siphon out the gas first to make tank removal "less" painful to remove
 

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The pump has a small rectangle filter that attaches to bottom of pump. Both sit right off the bottom of the tank within a baffled area...not a pump up high with a hose/tube running to the lowest point in tank

The pump sits inside the whole sending/float assembly. You remove that and then remove the pump from within the assembly...or just buy a whole new assembly

Have to drop tank and ideally you siphon out the gas first to make tank removal "less" painful to remove
We already have a new pump on hand from a Rock Auto sale, so we'll be swapping that in. Is there any consensus on the advisability of creating a fuel pump access port in the floor of the trunk? There currently is a junked Fleetwood in a local junkyard that could be used to create an appropriate cover for it.
 

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Is there any consensus on the advisability of creating a fuel pump access port in the floor of the trunk? There currently is a junked Fleetwood in a local junkyard that could be used to create an appropriate cover for it.
Having a "access hole" would make the swap way easier. IDK off hand where the hole would wind up in the trunk. The B-body tank the pump is forward on DS. IDK where it is on FWB

F-body guys do this often. Some just hack it with a saw and peel it back...some do a more "finished" type of cover

You could cut a larger donor section out from a junkyard car and then trim it down to be slightly larger than your access hole and use sheet metal screws to hold it on

The hole would need to be at least a 6" hole, maybe larger...assuming you cut the hole dead nuts over the pump. IDK how close the top of tank is to trunk bottom so you would have to drill a small hole first and probe through it to determine how much space you have. Maybe using a cut off wheel type of tool vs a sabre saw

Maybe someone has done this and can offer some tips...although IDK if that is a direct reference to FWB

IDK why every car with a in tank fuel pump does not have a access hole...my old Toyota did
 

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A

As Ballss suggested, hit the bottom of the tank and see if you can get the pump to wake up and at least get you home. In my experience, I found I had to have someone key the car on and hit the tank at the same time. This will only apply power to the pump for about 2 seconds. If you time it right, it helps to have power there as you hit the tank. You need someone in the car to turn the key as you hit the tank. Another option would be to use the prime override (test) wire to keep power applied to the pump while smacking the tank.

I've done my share of tank drops before but don't think it would be easy without at least jacking up the rear so you can get access to the hose connections and strap bolts. I prefer to remove the 2 15mm bolts at the front of the tank and let the straps swing down. Honestly, I would not recommend cutting the floor since it's really not that difficult to drop the tank. Not to mention you need to seal things well and any exhaust leaks could find their way into the cabin. Just something to consider.

I believe that a LOT of the pump failures we see are more of an issue with the intank wiring and/or the sending unit. Inspect connections carefully and refer to the rebuild your sending unit thread for more details. Highly recommend a new intank harness and be sure to get a new filter sock/strainer for the bottom of the pump. GL.
 

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IDK why every car with a in tank fuel pump does not have a access hole...my old Toyota did

It seems to be a nigh-unique oversight of American makers. Every import I’ve ever had to replace an in-tank pump on had an access panel, every post-1980 domestic didn’t. It’s needless and stupid ‘cost savings.’

My Bronco is of course the same way. The universal attitude of people that don’t have truly concours class Broncos is to cut an access hole (plans/templates readily available in their forums) then find a derelict F-150 bed and cut a panel out of it the appropriate size as a cover. Some people take it a step further and clean it up so much that you can’t tell it wasn’t factory.

As for this FWB, we’re still figuring out how to get it back to somewhere I can work on it. I went by it after work to see if just sitting and cooling off had helped. It hadn’t, nothing changed. The pump is audibly running during priming but the engine doesn’t even try to start. A rainstorm prevented me from popping the hood to check fuel pressure, though.
 

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you will have to lift the vehicle to drop tank .

if the pump runs and your fuel pressure is zero then the pickup may have fallen off.
pump not running then is there volts at the fuel pump connector with it connected to pump ..

wiring in the trunk and connectors/grounds in trunk .. driver side .

hole cut in trunk is a common process in some vehicles . reason is those vehicles it is a big PITA .... this vehicle is not all that hard to drop unless it is with a lot of fuel in it .

if you do want to put a door in , for access , then drop tank a small amount and locate the pump position use cutoff wheel so you do not damage the trunk floor .. then you can get some metal to place on the cutout edges.. rivet in place .. then use some sealer to seal the seams . the sealer will hold the steel cover in place on the trunk floor .. so if you need to remove it just use a scraper tool to lift up the door .
 

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I cut a hole in the sedan I once had. The tank was full and there was a foot of snow on the ground. Not caring about the car I just went crazy with a cutoff tool. The humped area that the spare sits in was directly over the pump. I cut a large area, replaced pump and put silicone on the cut seams. Couple strips of steel and some screws held it in place. Couldn’t see it once carpet was down and spare was in place.

Getting ready to put a new sender/pump in my current wagon. Thankfully it is a want and not a need. Waited until it was nearly empty before parking it :)
 

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Just look at the design and shape of the sending unit for our cars. The access hole that will need to be cut will be LARGE. I believe this cutting will also take you right thru the Spare Tire mount in the trunk. If none of this bothers you then have at it.

Personally, I think that is much more work than it would be dropping the tank. If you do things correctly and use quality parts, the odds of dropping the tank again are pretty slim. What is done in a Fbody may not equate to what needs to be done on a Bbody.
 

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What is done in a Fbody may not equate to what needs to be done on a Bbody.
Yes I believe the F-body tank drop is considerably more involved than B-body

It does help to have someone helping stabilize the tank while lowering it with a floor jack to remove

It has been several years since I put in a 255 LPH pump and I did it by myself

Yes it would be WAY more service friendly if GM made a access panel in trunk

Looking at the tank pic I see the pump is center/front. This looks to be more where the spare tire hold down is
 

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I've replaced one fuel pump in 20+ years. If anyone's going through them much faster than that. Then something's likely to be getting overlooked. Or,they're buying crappy pumps. Cutting an access hole is far more work than it's worth. The hole will be huge to clear the fuel lines,and spare tire holder will be gone as well. Don't cut trunk,it's a huge mistake...
 

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Don't Hate Me -

- hate my wife. I had forgotten all about the pump I had to replace in my old FWB. It died in a local gas station and I strongly suspected the pump. I called my wife to bring some tools to check things out (mostly a BFH and some jump wires). She says I could just call AAA for a free tow.

Being the mechanical marvel he-man as I am I forgot all about her getting the service for me a year earlier as a gift. Well 45 minutes later it's in the driveway. Yes, the wife felt great I used her B-Day gift after all.

Cliffs: A tow sounds way more better value for overall quality of life compared to slicing and dicing up a car in a parking lot. And figure all the money you already saved compared to poor hapless kids or women left to pay shop rates for that pump replacement.

 

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Yes I believe the F-body tank drop is considerably more involved than B-body

It does help to have someone helping stabilize the tank while lowering it with a floor jack to remove

It has been several years since I put in a 255 LPH pump and I did it by myself

Yes it would be WAY more service friendly if GM made a access panel in trunk

Looking at the tank pic I see the pump is center/front. This looks to be more where the spare tire hold down is
That is exactly where it is at and a big hole has to be cut.

B Body is cake compared to an F that requires exhaust removal, shock removal among other things.
 

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Yikes!! That is one LARGE access hole.

Maybe it's different on a wagon to drop a tank but not something I would want to do on a sedan. To me, it's really not a difficult job to just drop the tank, just a little bit of a PITA.

On a BoF car I guess it wont hurt too much structurally to cut a big ole hole in your floor but certainly would not do that on a unibody car. It still seems like a lot of work to me as opposed to just dropping the tank. Sure a tank drop is no fun, but not like you have to do it that often if done correctly.
 

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Wagon and sedan are about the same for dropping the tank. The first time it is a big chore, but if you ever have to do it again, it pays for itself in labor, and for those without a lift, it makes the job almost friendly. It is suggested that you do not cut the floor with the tank in place. Attachment screws need to be short and have blunt ends, even better is studs like the ones that hold the coolant overflow tank to the wheelhouse.

Cutting a hole in a unibody will probably not harm the structure, especially if a panel is bolted over it. E.g. a sunroof cut in a unibody does not destroy the integrity of the body.
 

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Bumping an older thread here.. Does anyone that has cut an access hole in the TRUNK of a SEDAN have pics or a template?
 

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Really,really bad idea. The hole will end up being huge to allow clearance for lines. You'll also lose mount for spare tire. Far less work to simply drop the tank,unlike F-Body where the access hole makes more sense.
 
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