FUEL PUMP ACCESS HOLE
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From: Bertram (outside Austin), TX
Car: 87 GTA
Engine: L98
Transmission: 700R4
Axle/Gears: Dana M78 3.27 posi
Re: FUEL PUMP ACCESS HOLE
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From: La Grange Park, IL
Car: 1987 Iroc Z28/ 1982 Z28
Engine: 355 TPI IP/ 305 CFI
Transmission: T-56/ 300C
Axle/Gears: 3.42 Open/ 3.73 Posi
Re: FUEL PUMP ACCESS HOLE
you know it will be
in a few days.. maybe even hours
in a few days.. maybe even hours
Joined: Aug 2006
Posts: 12,806
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From: Central NJ
Car: 86 Trans Am
Engine: 408 stroker sbc
Transmission: TKO600
Axle/Gears: Moser full floater m9, 3:70 trutrac
Re: FUEL PUMP ACCESS HOLE
there is always hope, have to think positively.
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Joined: Sep 2008
Posts: 15
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From: Garrochales, PR
Car: 84 Berlinetta
Engine: 305
Transmission: 700R4 TransGo Kit
Axle/Gears: Lock-Right
Re: FUEL PUMP ACCESS HOLE
The pics are pretty self explanatory. First cut the lines by hand using a hacksaw, then another inch on the lose lines with a mini pipe cuter to get some room. DON,T EVEN THINK ABOUT USING AN ELECTRIC TOOL ON THE LINES, YOU DON,T WANT ANY SPARKS FLYING AT TIS POINT. Cut the wires and splice with blade connectors. I use hi quality fuel injection hose because it stays flexible, cheap fuel hose tend to get hard as a pipe and have to break it each time you disassemble the thing.
Last edited by pihun; Oct 28, 2009 at 05:15 PM.
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From: Garrochales, PR
Car: 84 Berlinetta
Engine: 305
Transmission: 700R4 TransGo Kit
Axle/Gears: Lock-Right
Re: FUEL PUMP ACCESS HOLE
Here used an industrial coating over the scratches and edges.
The strainer was in bad shape so removed and put a 3/8 hose, a little longer and angled so the tip seat horizontal in the bottom.
I happen to have a nice aluminum plate with some sort of "noise dampening material". Fixed with a small line of window silicone around the edge, just enough to leave the fumes outside and the next repair it just pry of easily. Don't want to drill screws because cutting over the tank was scary enough. Unless you are planing to carry a stove in the rear there is no need for screws, the carpet is so thick that it is not going anywhere.
The strainer was in bad shape so removed and put a 3/8 hose, a little longer and angled so the tip seat horizontal in the bottom.
I happen to have a nice aluminum plate with some sort of "noise dampening material". Fixed with a small line of window silicone around the edge, just enough to leave the fumes outside and the next repair it just pry of easily. Don't want to drill screws because cutting over the tank was scary enough. Unless you are planing to carry a stove in the rear there is no need for screws, the carpet is so thick that it is not going anywhere.
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Joined: Sep 2008
Posts: 15
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From: Garrochales, PR
Car: 84 Berlinetta
Engine: 305
Transmission: 700R4 TransGo Kit
Axle/Gears: Lock-Right
Re: FUEL PUMP ACCESS HOLE
The perfect crime...
And my needle is happy again...
!!! Puerto Rico lo hace mejor !!!
And my needle is happy again...
!!! Puerto Rico lo hace mejor !!!
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Joined: Sep 2008
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From: Garrochales, PR
Car: 84 Berlinetta
Engine: 305
Transmission: 700R4 TransGo Kit
Axle/Gears: Lock-Right
Re: FUEL PUMP ACCESS HOLE

Is that trazodone on the pic...
I think it read at the bottom "Don't operate hevy machinery or cut over fuel tanks wile using this medication"...
Just joking, don't take me bad, I have aripiprazole on mine.
Last edited by pihun; Oct 28, 2009 at 05:22 PM. Reason: orthographic mistake
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From: Upland Pa
Car: Camaro Vert
Engine: 355 HSR
Transmission: A4
Axle/Gears: 3.73 S60
Re: FUEL PUMP ACCESS HOLE
I agree with arrow it takes me 2-3 hours to change a pump out in a thridgen. Buddy of mine and I have the record in about an hour with using air tools and hour 30 on the ground. With little tools and a dying flashlght. The bolts consist of mostly 7mm, 10mm, 13,mm 14mm, 15mm and 18mm. Granted that time frame doesn't take into acount for cars that have never been torn apart rusted to crap suspension parts. Even at that, it would be a good time tto upgrade that stuff also. Being as it is prolly shot also.
That was funny has hell that night at the car show. Being heckled by a bunch of e-list I signed every paycheck over to have my car built for me ******. While having the complete pump changed out in 1.5 hours start to finish.
BTW Uncle Tom I do know what huck bolts are and use many of them a day. They aren't rivets. Rivets are shot with an impact/rivet gun and huck bolts are pulled.
That was funny has hell that night at the car show. Being heckled by a bunch of e-list I signed every paycheck over to have my car built for me ******. While having the complete pump changed out in 1.5 hours start to finish.
BTW Uncle Tom I do know what huck bolts are and use many of them a day. They aren't rivets. Rivets are shot with an impact/rivet gun and huck bolts are pulled.
Last edited by Kat; Oct 28, 2009 at 06:03 PM.
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From: Bessemer City NC
Car: 89 RS, 93 Z28
Engine: Vortec 350 TBI, Lt1 6 Speed
Transmission: 700R4
Re: FUEL PUMP ACCESS HOLE
I was thinking about doing this but would like to use compression fittings on the lines so I could unhook them easily, does anyone know what size the fuel lines are so I can get the correct fittings? Or does anyone know a easier way of doing it except for using rubber hose and clamps because if I am not mistaken one of those lines are high pressure
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Joined: Jan 2006
Posts: 726
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From: League City, TX
Car: 90 Formula -- tot resto in progress
Engine: 350
Transmission: 700R4 w/ 2500 stall, by Owen @ ARD
Axle/Gears: 3.23 posi disc
Re: FUEL PUMP ACCESS HOLE
Main supply => 3/8"
Return side => 5/16"
Vapor Canister line => 1/4"
The fourth line appears to be some kind of pressure vent.
For better or worse, I just plugged this one.
Lowe's/H-D don't have a very good selection of 5/16 fittings.
Probably have better luck at an independent Ace Hardware store.
Good luck
Return side => 5/16"
Vapor Canister line => 1/4"
The fourth line appears to be some kind of pressure vent.
For better or worse, I just plugged this one.
Lowe's/H-D don't have a very good selection of 5/16 fittings.
Probably have better luck at an independent Ace Hardware store.
Good luck
Junior Member
Joined: Apr 2009
Posts: 73
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From: KS
Car: 84 Monte
Engine: 355 Chevy HSR
Transmission: T56
Axle/Gears: 3.90 Ford 9"
Re: FUEL PUMP ACCESS HOLE
This is always a funny subject. Half the people yell "No!" the other half yell "Yes!"
Personally I admit I did do this to my 92 RS. However I had just converted from TBI to HSR, built the motor from scratch, ran into a TON of problems, and in the end I still had to swap the pump.
After all that work, dropping the tank was the last thing I wanted to do. So I cut the famous hole.
Now I am a mechanic, and No I would not do this to other people's vehicles. Unless it was a close friend with consent to do so. That was not the case though. After 30 minutes the pump was in and ready to go. Total life saver IMO.
Personally I admit I did do this to my 92 RS. However I had just converted from TBI to HSR, built the motor from scratch, ran into a TON of problems, and in the end I still had to swap the pump.
After all that work, dropping the tank was the last thing I wanted to do. So I cut the famous hole.
Now I am a mechanic, and No I would not do this to other people's vehicles. Unless it was a close friend with consent to do so. That was not the case though. After 30 minutes the pump was in and ready to go. Total life saver IMO.
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Joined: Dec 2003
Posts: 279
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From: Pennsyltucky
Car: '91 Firebird (blown apart)
Engine: *cough*BOAT ANCHOR*cough*
Transmission: Slushbox
Re: FUEL PUMP ACCESS HOLE
Originally Posted by Vice04
This is always a funny subject. Half the people yell "No!" the other half yell "Yes!"
https://www.thirdgen.org/forums/body...tall-easy.html
Last edited by Derth Deboblo; Nov 14, 2009 at 02:35 PM.
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Joined: May 2003
Posts: 86
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From: Riverdale, GA
Car: 86 Trans Am
Engine: 350 Roch-4bbl
Transmission: 700R4
Axle/Gears: Normal
Re: FUEL PUMP ACCESS HOLE
I blew out the original 305 (nice motor but when you have to power merge on to a highway from a stand still and car are going over 70mph and after 15 minutes you have to get on the highway somewhere down Georgia, loaded with your honey and luggage for your trip to the Fl Keys. 0 to 70 just takes a long time.) could not find another 305, so I seen a junk yard in NJ with a 350 TBI off a 92 RoadMaster(cool name, lots of torque)) estate wagon, Converted it back to a Carb Setup for my pretty little Quadrajet. Now I have this noise in the rear of my car when fuel is low and I make a sharp turn. "CLANK, CLANK, CLANK, CLANK, CLANK, CLANK".
It goes on till I get more gas in the car. I have an external fuel pump by the tank. I wanted to get a internal one for the tank but I was intimidated into dropping the tank and puting a new one in. I read a thread that said one member drooped his tank for time in one year with pumps from autozone and advance autoparts. so I didn't wanna go thru that.
This is a great Idea you got, thanks for turning on unused brain cells. My interstate transportation capsule will be even more easier to service and that is one less thing to worry about when your going on 4000 to 5000 mile round trips, a couple of times a year
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From: ocklawaha FL.
Car: 81z-28,89gta,91z-28 03 1500
Engine: 355,L98vette tpi,327
Transmission: TH350/700R4/700r4/4l80E
Axle/Gears: 3;73/3;27/2;73/3;73
Re: FUEL PUMP ACCESS HOLE
Heck yeah!I love this mod!!I did mine on my 91-z before tony posted this.Got my info from that tta thread.If you ask me,this is the (right)way!
But all you purists out there including the ones that said I was doing a hack job back then and just love the idea now..haha!!
Next time I need shocks,maybe I should drop the fuel tank first.That would make the upper bolts easier to gain access with an open end wrench...
But all you purists out there including the ones that said I was doing a hack job back then and just love the idea now..haha!!

Next time I need shocks,maybe I should drop the fuel tank first.That would make the upper bolts easier to gain access with an open end wrench...
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Joined: Apr 2008
Posts: 30
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From: SUNNY FLORIDA
Car: 91 R/S - IROC-Z SUSPENSION
Engine: 1970 350 LT1 BORED 30 OVER -355/
Transmission: 5 SPEED
Axle/Gears: 3.73 12 BOLT POSI
Re: FUEL PUMP ACCESS HOLE
What would be (clanking)? Your fuel pump is external you stated.WHY PUT A INTANK BACK IN?????
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Joined: May 2003
Posts: 86
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From: Riverdale, GA
Car: 86 Trans Am
Engine: 350 Roch-4bbl
Transmission: 700R4
Axle/Gears: Normal
Re: FUEL PUMP ACCESS HOLE
when fuel gets low real low, external electric pump mounted by gas tank, pump gets an air pocket. the sounds is not clank clank clack. it's more like a rapid pulsating sound. that a little embbarassing.
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Joined: Apr 2008
Posts: 30
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From: SUNNY FLORIDA
Car: 91 R/S - IROC-Z SUSPENSION
Engine: 1970 350 LT1 BORED 30 OVER -355/
Transmission: 5 SPEED
Axle/Gears: 3.73 12 BOLT POSI
Re: FUEL PUMP ACCESS HOLE
I can understand that..Did you put a long enough piece of fuel line in the tank ..I am going to use a carb style fuel sender pickup from a carbed camaro 1985.....
Member
Joined: Oct 2006
Posts: 167
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Car: 1991 Chevrolet Camaro RS Red
Engine: 305 V8 TBI
Transmission: TH-700R4
Re: FUEL PUMP ACCESS HOLE
im sorry to say it but my access hole is just like yours when my fuel pump pukes on side of the highway on dont have to leave my baby long for someone to bust the windows out i throw in a pump and im back on the highway within the hour and i dont even get my clothes dirty, i cut out an access hole covered it with a section cut from a semi mudflap and covered it with the carpet, i cant tell its there nor can anyone else.
Member
Joined: Sep 2002
Posts: 153
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From: Texas
Car: 1985 Pontiac Trans Am
Engine: 305TPI
Transmission: 700R4
Re: FUEL PUMP ACCESS HOLE
All I've got to say is that this looks way better than the hack job done on my car. The idiot that had mine cut it with a torch on three sides and bent the flap up. Then he hammered it back down and went bondo crazy. So I'm going to have the body shop fix this when the car gets stripped for paint.
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From: MN
Car: 1982 Camaro
Engine: 555 BBC
Transmission: TSI Glide
Axle/Gears: Aluminum Moser 3.89
Re: FUEL PUMP ACCESS HOLE
All I've got to say is that this looks way better than the hack job done on my car. The idiot that had mine cut it with a torch on three sides and bent the flap up. Then he hammered it back down and went bondo crazy. So I'm going to have the body shop fix this when the car gets stripped for paint.
Member
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Posts: 153
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From: Texas
Car: 1985 Pontiac Trans Am
Engine: 305TPI
Transmission: 700R4
Re: FUEL PUMP ACCESS HOLE
Joined: Jan 2003
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From: New Germany, MN
Car: 1986 Iroc
Engine: 5.3
Transmission: 4L80E
Axle/Gears: 9 Inch w/ 3.55
Junior Member
Joined: May 2003
Posts: 86
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From: Riverdale, GA
Car: 86 Trans Am
Engine: 350 Roch-4bbl
Transmission: 700R4
Axle/Gears: Normal
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Joined: Feb 2009
Posts: 559
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From: Everett, Washington
Car: 2006 GTO
Engine: LS2
Transmission: M6
Axle/Gears: 3.46 LSD
Re: FUEL PUMP ACCESS HOLE
Good job on the details, and the link to the TTA. Going to be using both as references to cut a hole in my Firebird. My Camaro on the other hand, is getting the fuel pump replaced the proper way. I guess I want to experience dropping the tank before I do the access panel in the Firebird.
Member
Joined: Aug 2006
Posts: 234
Likes: 1
From: new york
Car: 89camaro rs
Engine: 350tbi (needs carb!)
Transmission: 700r4
Axle/Gears: 32x in process
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From: Texas
Car: 1992 Formula Firebird
Engine: 305CID (LB9)
Transmission: World Class T5
Axle/Gears: 10-bolt, 4.10 gears
Re: FUEL PUMP ACCESS HOLE
Good job on the details, and the link to the TTA. Going to be using both as references to cut a hole in my Firebird. My Camaro on the other hand, is getting the fuel pump replaced the proper way. I guess I want to experience dropping the tank before I do the access panel in the Firebird.
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From: p'cola FL
Car: 88 iroc-z/28
Engine: 408 lsx
Transmission: 5800 stall
Axle/Gears: 4.71
Re: FUEL PUMP ACCESS HOLE
im for replacing with external, which i have done.
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From: Texas
Car: 1992 Formula Firebird
Engine: 305CID (LB9)
Transmission: World Class T5
Axle/Gears: 10-bolt, 4.10 gears
Re: FUEL PUMP ACCESS HOLE
Making three cuts in the floor with a cutting torch (for a larger hole than is needed) along with bending the flap upwards is the wrong way. Folding it back down leaving a distorted side, then going Bondo crazy to fix it is wrong. That's what the former owner of my car did. Trust me there is a right way and a wrong way to do everything. Now the people who cut clean holes in their floors and made proper fuel pump access covers made a modification to make changing the fuel pump easier. I have no problem with that and wouldn't call it wrong. Dropping the tank and going that route is what's probably in the GM service manual for these cars and in no way compromises the structure of the vehicle. I'd call that the right way to do things.
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Joined: Feb 2009
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From: Everett, Washington
Car: 2006 GTO
Engine: LS2
Transmission: M6
Axle/Gears: 3.46 LSD
Re: FUEL PUMP ACCESS HOLE
I'm dropping the tank to replace the fuel pump. If I have to drop it again any time soon, then I'm making an access hole AFTER I drop the tank to prevent any unnecessary damage to the tank or sending unit.
My first time dropping the tank with my Camaro, over the weekend, took me only two hours and no manual for a reference!
I'm a purist when it comes to my Camaro (first car), but my Firebird, that has future drag strip plans.
My first time dropping the tank with my Camaro, over the weekend, took me only two hours and no manual for a reference!
I'm a purist when it comes to my Camaro (first car), but my Firebird, that has future drag strip plans.
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From: Renton, WA
Car: 1985 Camaro, 1986 Trans Am
Engine: 5.0L carbed and 5.0L TPI
Transmission: TH700R4
Axle/Gears: 3.23 and 3.27 posi
Re: FUEL PUMP ACCESS HOLE
The time my fuel pump died 50 miles from home I was glad I had that access hole (and that there was a Schucks within walking distance)! Took all of 10 minutes to swap the pump and I was on my way home without having to have my car towed.
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Posts: 2,565
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From: Texas
Car: 1992 Formula Firebird
Engine: 305CID (LB9)
Transmission: World Class T5
Axle/Gears: 10-bolt, 4.10 gears
Re: FUEL PUMP ACCESS HOLE
I'm probably going to go with an in-line unit so that I can do things easily without hacking up the car.
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Joined: Mar 2001
Posts: 2,262
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From: Renton, WA
Car: 1985 Camaro, 1986 Trans Am
Engine: 5.0L carbed and 5.0L TPI
Transmission: TH700R4
Axle/Gears: 3.23 and 3.27 posi
Senior Member
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From: south of kansas city
Car: 86 berlinetta 92rs gfx
Engine: 4 bolt 384 stroker
Transmission: th350 4000 stall manual/T brake
Axle/Gears: 87 iroc 9 bolt
Supreme Member
Joined: Mar 2001
Posts: 2,262
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From: Renton, WA
Car: 1985 Camaro, 1986 Trans Am
Engine: 5.0L carbed and 5.0L TPI
Transmission: TH700R4
Axle/Gears: 3.23 and 3.27 posi
Re: FUEL PUMP ACCESS HOLE
There was a good 1/2"-3/4" between the body and tank in my Camaros ( I did this to my '85 Z28 too back in the day ) so if you're careful and not using a torch like an idiot, there isn't much chance of damaging anything.

BTW, this mod is a lifesaver for emergency roadside repairs.
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From: p'cola FL
Car: 88 iroc-z/28
Engine: 408 lsx
Transmission: 5800 stall
Axle/Gears: 4.71
Re: FUEL PUMP ACCESS HOLE
Making three cuts in the floor with a cutting torch (for a larger hole than is needed) along with bending the flap upwards is the wrong way. Folding it back down leaving a distorted side, then going Bondo crazy to fix it is wrong. That's what the former owner of my car did. Trust me there is a right way and a wrong way to do everything. Now the people who cut clean holes in their floors and made proper fuel pump access covers made a modification to make changing the fuel pump easier. I have no problem with that and wouldn't call it wrong. Dropping the tank and going that route is what's probably in the GM service manual for these cars and in no way compromises the structure of the vehicle. I'd call that the right way to do things.
a properly cut hole, if you will, is an option like you mention above.
some people are hacks.
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Joined: Feb 2010
Posts: 18
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From: Saucier, Mississippi
Car: 91 RS, 62 T-BIRD
Engine: 3.1V6, 300hp390, 96ci panhead
Transmission: auto od
Re: FUEL PUMP ACCESS HOLE
My 91 RS was cut when I got it. Didn't even know till I had fuel pump problems. It isn't any where near as neat a job as Tony's, I will clean it up later. but my question is do you have enough clearance to remove the sending unit without cutting the tubes if you do use tube unions with the slip on flares to reconnect the tubes, as the modifyer of mine failed to use, hose & clamps don't cut it.
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Joined: May 2004
Posts: 279
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From: San Diego CA
Car: Badass 1991 Firebird
Engine: Screamin' 305 TBI
Transmission: 700R4
Axle/Gears: 2.73, 3.42's waiting to go in!
Re: FUEL PUMP ACCESS HOLE
Great post, and you did a good job. I did the same thing last summer. I had a mechanic drop my tank about two years ago, to install a new pump, he did it all in about three hours, in a driveway. Then last year the car had to take a fuel system pressure test (new CA smog test) and failed, meaning the tank had to be dropped again.
A lot of these cars have leaky gas tanks, around the fuel filler neck and top of tank, there was even a recall for fuel filler necks on some cars, mine included but don't think it was ever taken in for repair.
I JB welded around the tank neck which was loose, but a smoke test showed a vapor leak coming from the top of the tank. So I cut a hatch as you did, above the fuel tank, cleaned and sealed everything and now it is all tight as a drum, passed the pressure test, and makes a big sucking noise when you take off the gas cap especially when not much gas in the tank.
Plus now I have the access hatch which is handy. Right now I just have the sheet metal duct taped over the hole, but planning to put a nice metal plate on there as you have.
Hard to say which method is better, of course dropping the tank is "doing it by the book" but the hatch is a shortcut making future repairs easier. And yes I've read the power window thread, I think I know which way I'll go on that one...
A lot of these cars have leaky gas tanks, around the fuel filler neck and top of tank, there was even a recall for fuel filler necks on some cars, mine included but don't think it was ever taken in for repair.
I JB welded around the tank neck which was loose, but a smoke test showed a vapor leak coming from the top of the tank. So I cut a hatch as you did, above the fuel tank, cleaned and sealed everything and now it is all tight as a drum, passed the pressure test, and makes a big sucking noise when you take off the gas cap especially when not much gas in the tank.
Plus now I have the access hatch which is handy. Right now I just have the sheet metal duct taped over the hole, but planning to put a nice metal plate on there as you have.
Hard to say which method is better, of course dropping the tank is "doing it by the book" but the hatch is a shortcut making future repairs easier. And yes I've read the power window thread, I think I know which way I'll go on that one...
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From: Mesquite, Texas
Car: 89 rs, 86 Trans Am
Engine: RS-V6... Trans Am-LG4
Transmission: RS-T5... Trans Am 700r4
Re: FUEL PUMP ACCESS HOLE
As somebody that has been stranded by a fuel pump going out (my 85 sport coupe, about 10 years ago) I have two questions about this topic, and would appreciate a clear answer without judgement and finger pointing from either side of the debate
first... is there a tech article written with the step by step PROPER way to change a fuel pump? If not, I would love to see one to show people that it's do-able for the average shadetree mechanic
second... for those who choose the access hole method. Are rubber hoses really a proper way to repair the fuel lines that have to be cut? can rubber relaly support high pressure fuel long term,or is it a disaster waiting to happen? Has anybody here ever used a double flare tool to create a real fuel fitting, and retain the full metal tubing?
I'm keeping an open mind about this mod, but if the fuel line issue can be addressed, I think it's a valuable option. I wasn't in a position 10 years ago that I could drop the tank and rear end, but if i could fix it on the side of the road, it would have saved me hundreds of dollars
first... is there a tech article written with the step by step PROPER way to change a fuel pump? If not, I would love to see one to show people that it's do-able for the average shadetree mechanic
second... for those who choose the access hole method. Are rubber hoses really a proper way to repair the fuel lines that have to be cut? can rubber relaly support high pressure fuel long term,or is it a disaster waiting to happen? Has anybody here ever used a double flare tool to create a real fuel fitting, and retain the full metal tubing?
I'm keeping an open mind about this mod, but if the fuel line issue can be addressed, I think it's a valuable option. I wasn't in a position 10 years ago that I could drop the tank and rear end, but if i could fix it on the side of the road, it would have saved me hundreds of dollars
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From: Bertram (outside Austin), TX
Car: 87 GTA
Engine: L98
Transmission: 700R4
Axle/Gears: Dana M78 3.27 posi
Re: FUEL PUMP ACCESS HOLE
Only 1 of the 4 lines back there are under pressure, so rubber hose (the proper stuff) is perfectly safe to use. TBIs & carbs use a much lower pressure than TPI, LT1 & LS1, so only 1 lines really needs the lines flares & the correct fittings put on.
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From: Mesquite, Texas
Car: 89 rs, 86 Trans Am
Engine: RS-V6... Trans Am-LG4
Transmission: RS-T5... Trans Am 700r4
Re: FUEL PUMP ACCESS HOLE
what about MPFI? Do you know what kind of pressure we're talking about there?
if I flare, is double flare needed, or will single do?
if I flare, is double flare needed, or will single do?
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From: Mesquite, Texas
Car: 89 rs, 86 Trans Am
Engine: RS-V6... Trans Am-LG4
Transmission: RS-T5... Trans Am 700r4
Re: FUEL PUMP ACCESS HOLE
it's ok. If I do the mod I'll probably get the flare kit to be safe. It's only like $30 from amazon. that's nothing for a tool
its good to know i only have to do that line, if anybody else has the pressure for the v6's, I'd still like to know
its good to know i only have to do that line, if anybody else has the pressure for the v6's, I'd still like to know
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From: Mesquite, Texas
Car: 89 rs, 86 Trans Am
Engine: RS-V6... Trans Am-LG4
Transmission: RS-T5... Trans Am 700r4
Re: FUEL PUMP ACCESS HOLE
thanks. If I do this, I'll make sure I use flared lines.
Now... does anybody know if a tech article for the regular way to do this? It's funny how there are several how to article for the hole method, and certain people flame them, but I can't find one on the "right" way
Now... does anybody know if a tech article for the regular way to do this? It's funny how there are several how to article for the hole method, and certain people flame them, but I can't find one on the "right" way
Re: FUEL PUMP ACCESS HOLE
No need to repeat the exact process laid out in a Haynes or service manual. Plus anyone with basic automotive knowledge will be able to figure it out. There really isnt anything tricky about it
Member
Joined: May 2004
Posts: 279
Likes: 0
From: San Diego CA
Car: Badass 1991 Firebird
Engine: Screamin' 305 TBI
Transmission: 700R4
Axle/Gears: 2.73, 3.42's waiting to go in!
Re: FUEL PUMP ACCESS HOLE
Hi, as for the right method to do the access hatch, there are a few ways but the main thing is not to make sparks or puncture the tank, obviously. Seems to me I drilled a hole (very carefully) to start my cuts, then used tin snips and the metal is fairly easy to cut.
Since the fuel pump itself uses a rubber hose to feed the lines, I'm sure rubber is fine, plus some cars use rubber lines with clamps for engine bay fuel supply. With the hatch, you can inspect things now and again, even so if the clamps are tight it should be fine.
A note of caution, be careful using "fuel system cleaners" such as Techron, as they tend to eat things. It was after a big bottle of Techron that my fuel pump went out, and it was the rubber supply line that was deteriorated (after almost twenty years of sitting in gas), pump still worked.
Since the fuel pump itself uses a rubber hose to feed the lines, I'm sure rubber is fine, plus some cars use rubber lines with clamps for engine bay fuel supply. With the hatch, you can inspect things now and again, even so if the clamps are tight it should be fine.
A note of caution, be careful using "fuel system cleaners" such as Techron, as they tend to eat things. It was after a big bottle of Techron that my fuel pump went out, and it was the rubber supply line that was deteriorated (after almost twenty years of sitting in gas), pump still worked.
Joined: Sep 2002
Posts: 3,685
Likes: 10
From: PA
Car: 86 Trans AM
Engine: LS1 (not stock...)
Transmission: Built T56
Axle/Gears: Strange 12-bolt w/ 3.73
Re: FUEL PUMP ACCESS HOLE

The reason you wont find instructions on how to do it the "right" way in this thread is because the people that have performed the "hole mod" already know how to do it the "right" way and choose to go a quicker, easier route. This is more catered to the fabrication involved in performing the mod.
Check the other sections of the site for more stardard procedures...but like Pocket said, its pretty straight forward once you get under the car start looking at the guts. Exhaust comes out, axles has to drop (meaning shocks unbolted, etc), some heat shields come off... Its not real hard work, just time consuming.
J.
Re: FUEL PUMP ACCESS HOLE
Since the fuel pump itself uses a rubber hose to feed the lines, I'm sure rubber is fine, plus some cars use rubber lines with clamps for engine bay fuel supply.




