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Fuel pump and pic of "hinged door" and measurements

sandiego21

Full Member
Joined
Feb 22, 2011
Messages
178
Location
Carol Stream, Illinois
I am planning on creating that access door to my fuel pump. I have been able to locate the pics of cutting the floor under the passender driverside seat. However, I remember seeing the pic of someone who installed hinges on the cut piece but can't seem to find it. Any help would be appreciative.

Also, not sure if the measurements are different, I have a 2003 Z71, does anyone have the measurements of where the pump actually is so when I cut the opening I won't be way off....this is definitley my anal side of trying to be "exact"

Thanks again for any help on these two issues!!! 
 
Why in the world would you cut a hole in the floor to get to the pump? How often do you plan to replace the pump?
 
Not often...however, in some vehicles that access door is created by the manufacture for convenience vs. dropping the gas tank. I am all for convenience, so that couple hours of cutting is well worth the expense of having the dealer or garage drop the tank...or for that matter me dropping the tank. I'm also for being proactive.

 
I too would like to make this mod to our 2002 Z71 since we have broken the 100K mark and are still running the original fuel pump.

From what I have read it seems as though I can change the pump myself, with the addition of this access port, and save some hard earned money.
 
I did the hole under the back drivers side seat in my 2002 2500 4x4 and the 2500 is not positioned quite the same as the 1500, so if anyone is going to do thier 2500 look back in the post last year for the pics I posted or hit me up and I'll find them or take more.
It's easy
David Deponty
 
Dropping the fuel tank is really very easy.  Im shocked people think cutting a hole in the floor is a good idea.
 
Bluez71 - I'm with you on that one. Just the thought of cutting the carpet makes me cringe. Maybe, and only maybe, if there were a kit that was produced that included a perfectly molded watertight hatch in a factory color with a trim ring for the carpet that looked OEM, I would consider it. Cutting into my AVY :badidea: Just my opinion, and I hope nobody takes offense.
 
You don't cut the carpet at all. The carpet is removed then the sheet metal is cut to gain access to the pump. Once the carpet is laid back down you would never know an access panel was cut.
 
TXSZ66AVLANCHE said:
Cutting the floor makes me sick, would drop the tank a thousand times before cutting the floor.

We seem to never have the choice when the fuel pump fails.  :E:
Say 25 + gallons of highly flammable liquid. You have no help just one floor jack I?m a man I can do this.
Ask my co-worker 8 months in a burn center countless gaffs.  Scared for live nearly lost his sons and home, lost three cars.
No how stupid is the hole in the floor, like it should have been engineered in.
Do I  :9: or burn!
JV
 
Changed pump before with full tank and only a floor jack, took serious precautions to ensure no heat source was in the area that may cause a fire. Its all about precaution.
 
In the future for AV 2500 owners who want to do the fuel pump access panel mod here are a few tips to make it a little easier..

1. Remove the back seat and roll back the carpet and pad.

2. Reach up between the frame and floor pan and using a tape measure and locate the approximate center of the pump housing.

3. Transfer the measurement to the inside floor and drill a 1? hole in the floor pan with a hole saw.

4. Layout an access hole approximately 5? x 7? (It does not need to be very large).

5. Using the 1? hole saw drill the four corners of the access hole you laid out and then using sheet metal snips or jigsaw connect the four holes.. Be careful the fuel line and wiring are about 2 to 3 inches below that is why I only used sheet metal snips..

6. Take a water hose and wash off the top of the tank and housing to remove any road debris and then blow it off with air to dry.

7. R & R fuel pump?. You will need fuel line disconnect tools or a small flat blade screwdriver and patience? Good time to upgrade, I installed a 255lph Walbro.

8. Fabricate new access cover out of sheet metal or do what I did and find an AV at the junk yard and cut out a large piece of the floor pan above the pump to be trimmed to fit and will match the floor contour perfectly. (Find this part before you need to change your fuel pump as I did)

9. Put down sound deadener. (Good time to do so but optional)

10. Roll back the carpet and pad, reinstall the back seat.

11. Cut two slits in the carpet and pad above the access panel from the back to the front for future access to the panel.

Now if you ever need to replace the fuel pump again it will be a 30 minute job and no need to drop the tank? Because of this forum I knew my pump would go sooner or later so I had all the parts and pieces before mine went out so I was only down a few days.. By the way mine went at 162,000 miles and I always filled up when I was on dead empty, so I don?t give any credit to some who think that causes fuel pumps to fail early or prematurely?




 

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SanDiego21,

The same applies to the 1500, just reach up between the frame and the floor above the tank and you can feel the top of the tank where the fuel pump is. Take a tape and measure approximate location and drill a 1" hole with a holesaw and then you can look through the hole to see exactly where to layout you access door. I also used a small mirror and flashlight to look at it from the side. You can see it and how much clearance there is.

Like I said you don't need a large access hole. I started with a small and 5" x 7" and that was all I needed to get the fuel pump module out. I had a large piece of floor from a 2500 AV from a junk yard and was ready to make a big access panel but I did not need it all. I just cut the piece about 1" larger all the way around, laid out holes for bolts and used silicon for the seal. The bolts are actually threaded through a piece of aluminum stock 1/8 x 1" wide and held to the floor from below with silicon.

I should have taken more pictures but wasn't thinking about it at the time.. Sorry

Some don't want to cut there floor, that's fine.. I didn't really want to either but the way I did it almost looks like it came from the factory that way. It should have some cars do have fuel pump access panels under a seat or in the trunk. The other reason I did it this way is I could not see having to pay the dealer or shop $500 to a $1,000 dollars to change a fuel pump that I can do for a $150 bucks. If it goes out on a long trip you would have no choice. And to me dropping the tank is a lot more dangerous and time consuming than doing it this way, especially if or should I say when it goes out again.

Good luck

Randy




 
Thanks Randy...didn't even think about looking under the car with a flashlight and mirror. There are other posts with measurements and I also like the idea of cutting a piece of the floor from one in a junk yard. I love the idea due to savings of a quick change versus dropping the tank. Yes, as other cars, this should have been done at the factory..expecially when it is hidden under the passenger seat.  Guess I have a great project to start this weekend. Thanks again for your pics, measurements and feedback!!! I will be sure to post pics of my project for others to see as well!!!!
 
I know its an old thread but look at it this way. You can never estimate when your pump will give, but of course you can always tow it home. I like most people travel alot and if my pump goes out while im on the road, either take a cab to the parts store or nearest dealers and grab a pump, or if I have a spare in my saddlebag all I have to do is pop the panel I previously cut, off, r and r the pumps, and im back on the road in 15 minutes. I love my truck so ill take the time to do the cut perfect, along with re attaching the panel to make it look professional. Its not so much as lazy or not mechanically inclined, but if I ever need it in the future, its there.
 
Here's a drawing (not to scale) of the way I did it..

The best way to me was to go the junk yard and cut a section of floor above the tank, that will look the and seal the best..
 

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Randy said:
Here's a drawing (not to scale) of the way I did it..

The best way to me was to go the junk yard and cut a section of floor above the tank, that will look the and seal the best..

I chose to bolt my plate back in too. The problem is that I slipped when drilling one hole and drilled a hole into the tank.

My plan is to get a SS screw to fit the hole, and screw it in with some sealant.

My question is, what is the best sealant to use?

Thanks.
 
I don't know about the 5200 being compatible with gas, I have a tube of the 4200 and it does not say anything about gas compatibility but I know "Marine -Tex" epoxy is impervious to gasoline and diesel.


Randy
 

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Hey fellas. Im new on this forum and to start of my first post...I need to replace my fuel pump!  :E:
Anyway, I think I can do this access hole deal and was wondering thoughts on using roofing tin to cover the hole?
Joe
 
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