mjjmike

I have been told that I need to replace my fuel pump on my Firebird, I have an 1989 Firebird BTW. I was wondering how many of you have went through the floor to get the fuel pump out. It would be under the carpet afterwards, and I suppose you could cut it neat and have a panel to replace it with but... If I have to take the tank down, I am going to have to cut the brand new exhaust system I just had put on it out, to get the tank down. Is this procedure safe? Worth it? Hard? Stupid as hell? I wanted some feedback from you guys. Thanks a bunch!


MRJ

cp87GTA

If you cut the hole you will have yo cut the steel fuel lines also. Then it's time to patch the lines also. I'd rather patch the exhaust than go through patching the panel and lines. Just my 02.

jimmy_mac

I cut mine out. And yes I ended up cutting the steel lines also. It was not the easiest thing I have ever done for sure. I was very concerned with cutting the fuel pipes cleanly and it was a pain. Really the high pressure fuel delivery line is the one that is probably most important to cut cleanly. I used high pressure hose to patch it together when I put it back it. I used tin snips to cut the hole in the body and it is not the cleanest hole in the world. You have to cover that hole with something if you do this. Exhaust fumes seam to really like to migrate there. The carpet will not do it. Make sure you use something to get a good seal <-(spelling).

Do I think this is the best way to do it? NO. Did it really make it easy when I replaced it with a pick-up tube a few weeks ago? Yes.

You know this post got me thinking. Maybe if I had cut the hole differently I could have just loosened the steel lines where you normally would when pulling the tank and pulled the whole thing out without cutting . Oh well, just don't do something you think you may regret.

89firechicken

i cut a hole in my bird as well i suggest if you take this route to flare the ends on the sender if you can and double clamp the high pressure hose as well ive replaced that pump a number of times, when i first got the car, when my car died on me the first time, when i found out i bought the wrong pump, then again when i switched to my tpi system, now i may have to change it because im going to run a stronger setup. but really i say drop the tank iv'e been told it's not that hard just make sure it's empty when you drop it out.

91banditt2

iTrader: (1)

not that hard? i spent a week trying to get mine out. and i never did!
after i cut the body open i used compression fittings to put it all back together it doesn't leak at all.
i'm glad i did this because in the last three months i've put three brand new Walpro pumps in.

GTA-SPD

I recently replaced my pump in my GTA and I dropped my tank. I thought I'd have to cut my exhaust too, but you can remove the hangers from the body, all of the heat shielding and the hanger at the tranny and that let the exhaust move farenough out of the way. You do have to let the diff swing down quite a bit, but that is pretty simple. The only hang up that I really ran into was the filler neck. That sucker don't come off of the tank and you have to tweak it a bit to get it out and back in. It only took me 4 to 4.5 hours start to finish (that includes pumping about 14 gallons of gas out of my tank). I would say that before you cut your floor out, seriously think about doing it the way it was intended to be done.

2xsess

Dude, don't say that, I just ordered my Walbro pump..why are yours going bad so often?



Thanks,
Jeff

91banditt2

iTrader: (1)

i couldn't tell you what happen to the pumps all i know is the first pump was only putting out 15psi at the fuel rails.at first i thought that Ron from www.apeusa.com seny me a pump for a TBI car.well it turns out that it was bad Ron said i should have a ohm reading of 1.7 i was getting 0.05(not good).i sent it back and Ron sent me another one.
the second pump was ok for a little while but started to put out only 10psi at the rail.so i pulled the second pump out and check the ohms value it read 0.04.as i was pulling the pump out i noticed there was a nice clean cut in the rubber hose attached the the pump,the cut wasn't there before!i pulled the hose off and looked inside of it the tip of the pump has a little cap on it to keep the check valve inside the pump.well needless to say the check valve came out of the pump as i was moving the pump around.at that point my emotional dial was set on KILL!!!!i sent it back and Ron sent me another pump and so far i haven't had any problems yet(knocking on wood)
through all this bullsit i have to say Ron was a stand up guy and he took care of me.but this will be the last Walpro pump that i ever buy,along with all the other aftermarket companies that just repackage the Walpro pump,Accell,BBK,etc,ect........

tazjet

i reciently replaced the pump in my 89 firebird. i cut the area above the tank and was able to remove the entire pump assembly intact without cutting the fuel lines. it took a little finesse and a little bigger hole but it did come out. loosen the tank straps and remove the gas fill door assembly loosen fittings on fuel lines and work with the pump assembly (be patient) if you can find someone to help with the removal, is easier with 2 people. one in back of car and one under car.good luck let us know how it goes .

FU-Q

i dont understand... isn't the fuel pump in the gas tank? why do you have to cut the floor or exaust pipes?

camaro6spd

I have a NAPA fuel pump....been workn great for 4 months.....cost me $54. Altho i had to remove my tank b/c the filler neck was bad and i was like this is suck a PITA i am just gonna replace the fuel pump while i am at it...lol....should have also replaced the fuel gauge sensor too...some time it is erratic above half.

Jim85IROC

iTrader: (2)

I hate seeing people do half-assed repairs like this. Cutting a hole in your floor to get to the fuel pump is like cutting a hole in the front fascia to do a cam swap.

Do it right and drop the tank! I did mine in less than a day, and I guarantee that you'll spend nearly a day dicking with it through the trunk floor anyway. You really think chopping up your car is worth the lousy couple hours that you'll save? If so, go buy a car with a warranty.

FJK

Yeah, Jim85IROC offers good advice. You won't be cutting a hole in the trunk floor, you'll be cutting a window opening, assuming you don't want to cut the fuel lines. Some tips I discovered in changing fuel pumps by totally removing the tank:
1) Easier if the tank is totally empty... so pump it out
2) The rear end really needs to be dropped down quite a bit.
3) Aside from the obvious to dropping the rear end (lower shock mounts off, etc), make sure you disconnect the rear sway bar either at the links or remove the frame brackets.
4) Unclip the hard brake line from the floor, (2 clips), because the rear brake hose really is the limiter of how far down the rear end can drop.
5) If the rear end drops down far enough, the tank does not have to be monkey f--- out. The key is, slow & ez with a helper, not brute force. The last thing you want to do is break loose or bend the filler neck.
6) Because of #5, I'm not sure if the exhaust system laying in the way will allow the rear end to drop down far enough. I've always had the exhaust removed, either because it was so new I could separate the joints or because it was so old, a new exhaust system was needed any how. At worse, cut the inlet pipe & have a muffler shop reweld it. Better yet, if possible, plan to replace your pump when you do your next exhaust system.
7) On the advice of my mechanic friend, use AC Delco fuel pumps & a new strainer. Discount prices: pumps $75-$80, strainers $7-$17.

Regards, FJK

91banditt2

iTrader: (1)

had it done in a couple hours
and that's with a couple beer breaks

Matt87GTA

Amen!!!!!!

F-BIRD'88

Mine was cut open by the previous owner.
I had to go in there to repair the fuel guage sending unit.
A real time saver. GM should have made an access hatch
in the floor in the first place.
I'd use a circular saw with a metal cut off blade.
Just adjust the depth of cut to just cut into the sheet metal
so you don't hit the tank or lines.

Cut a rectangular shaped door (3 side cut) so you can fold down the flap of steel when you are done.
You can fill the thin gap left after with automotive seam seal.

Marc 85Z28

iTrader: (3)

I agree with F-BIRD'88 on this one. GM should have done this from the factory. I had to replace a pump on a friends 85 TPI on a lift at work and it seemed pretty easy. Until you try to remove the tank - that fuel filler neck is a real PITA!! - even on a lift!

If I had to replace another one I'd cut "The Hole" and either do it flap style like F-BIRD'88 or cut a round hole and I'd place a large rubber grommet in there like most new cars.

You call it a hack job, I call it intelligent re-engineering. Just because GM designed it that way doesn't mean it's the best and only way. We all end up modifying our cars and "clearancing" to fit hi-po parts, why not a fuel pump?

Next time you need a pump, you won't say, "Oh $hit, I've gotta pull up that flap again and spend 30 minutes changing the pump!". However, you'll be cussing up a storm next time you remove that tank.

Guest

It is a hack job.

Rarely do the panels in the rear of the car split open in the case of an accident, its just bends and such. With a panel there, I dont think I have to explain what would happen. I think its a bad idea, for more reasons than one. Every picture I've seen of one of those hack jobs, you can see where the fuel lines have been seeping fuel all over the place. No thanks.

Ricktpi

It took 3.5 hours in my driveway. The RIGHT way.
Yes, empty the tank.
Yes, drop the rear down as far as possible with out ripping the brake hose.
Yes, take your time & double check everything when installing the pump on the sender.
Yes, disconnect or cut the exhaust.
NO, don't cut the floor, it's a slackers way out.

89firechicken

say what you want but last time it took me about 15-20 mins to remove and replace my fuel pump which left me about3 hours an 10 mins more to work on the 24 pack

Kevin Johnson

Madmax,

What would you think about making a custom panel of at least the same gauge as the floor and with edges that substantially overlap the opening? Maybe nut inserts could be spaced evenly around the opening so that the panel could be securely bolted down with either a rubber gasket or caulking of some sort.

I have an ATL fuel cell and that is essentially how the crash container surrounding the bladder is constructed.

As for the best way to cut and rejoin the fuel pipes, I don't know but it sounds like that might not be needed if the access hole is large enough (?). I agree about the leaking fuel being very worrisome. You might find out about that when your garage goes up.

I realize that with making the panel, etc. the amount of work involved would approach that of dropping the tank once. After that, though, you'd save some time.

Guest

Thats a better idea. Most of the ones I have seen pics of are just a plate screwed to the floor with sheet metal screws and sealed with silicone. Eh....
As for the lines, a double flare is the best way. Next, i'd use a bubbled end with FI hose and a hose clamp. Compression fittings suck, sometimes they are fine and sometimes they just seep just for the hell of it. They really are more trouble than they are worth IMO.

I cant even get my rear carpet out of the way in 15 minutes, let alone pull a plate and pump too.

89Z

I have to agree with the group that says DO NOT cut a hole in the floor to swap fuel pumps. Dropping the tank is not all that bad. Its all nuts and bolts. Just drain all of the gas out before starting the job. Drop the rear as far as you can after unhooking the rear brake hose clip and removing the shock bolts. There is absolutely no need to cut the exhaust. Just unbolt it at the catalytic converter, remove the hangers, and slide it to one side. The time spent fooling around pulling up the carpet, cutting the floor and trying to slip the pump assembly out through a hole that may or may not be in the right location can be spent unbolting things without hacking anything up. There is nothing worse than buying a car and finding out later someone hacked things up trying to take shortcuts. As far as "making it easier for the next time" what next time? Generally the stock GM pumps will go at least 150,000 miles provided the fuel filter is replaced periodically. My original stock pump went 178,000 miles. Many of the aftermarket pumps do not provide the same durability.

FJK

If you are going to change pumps on a car for the first time & the prior owner did not cut an opening, you are going to suffer a little either way. If you neversieze all the chassis bolts after doing it the first time, it won't be bad if you have to drop the tank for another reason. Cutting & resplicing those fuel lines....NO WAY, especially the high pressure line. I don't think you're going to get a long term, leak free connection no matter what you do. But then again, you won't be spending alot of time on those connections anyhow, because that would defeat the whole purpose of using the "cut a hole" method.
I've heard even some AC Delco pumps might not make 100K miles, but the majority do. I'd still use an AC pump & chances are you'd never go back into the tank to change the pump again.

91banditt2

iTrader: (1)

you all can say what you like?but i'll stay with doing it the easy way.how many of you have had to put three pumps in your cars in a span of two months?i have yet to have any leaks out of my compression fittings.


can we all just agree to disagree here?

89firechicken

i've done four in three im glad i have that hole because i dont have a garage i also have no leaks

Kevin Johnson

I guess I could be swayed either way (assuming the hard lines weren't a problem). I haven't had to replace the one in the RS yet (something to look forward to). However, I have had the experience of replacing the pump multiple times in other cars (poor quality replacements --- VERY aggravating).

FyreLance

I made an access panel in the rear hatch, and I'm glad I did, and I'd do it again in a second.

I did a good enough job so that fumes won't enter the cab (the sheet metal on my "access panel" is bigger than the whole and sits on top of it and is sealed.) Call it the slacker's way out and what have you, but cutting the hole and all that is still work, it isn't being lazy just because it's an easier method, it's just common sense. To those who did it the "right" way, good for you and that's cool that you did. But I'm just saying I'd have no problem doing it again. I do wish I would have cut the fuel lines at different lengths though, would've made re-connecting and clamping them much easier.

The panel is sealed and is covered by the rear carpeting and everything anyway, out of sight and out of mind, so... :: shrug ::

84 Challenge

I can't believe this post about cutting the floor! Why the hell would you wanna cut up your car? I just did an intake pump replacement a month ago. Yeah....it was a job to do in the hot Texas sun. But cutting a car for a fuel pump replacement?

TomP

Man, you guys do things the hard way, I'd NEVER cut the floor. And I've done my pump twice already!! It's really not that bad... a lot of work, but it's all annoying work, it's not hard. Besides, geez, what if you cut into the tank??? Sparks, explosion, see the connection? Ouch. So now that you're going to do the job the "real way", here's some quick tips:

1. If your tank still has fuel in it, consider hot-wiring the fuel pump from the front of the car (remember sparks+fuel=death) to pump the old fuel out. I took the fuel filter off, and put a scrap of heater hose over the tank outlet pipe (from the fuel filter) and aimed it into a gas can. I put the key "on" to watch the fuel gauge drop. Just be careful of SPARKS (disconnecting the pump hot-wire from the relay under the engine compartment), do this at your own risk, blah blah

2. Don't re-use the pulsator, the old o-rings can leak, and you'll be screwed. Either buy a new $40 pulsator or use a short piece of rubber hose (usually comes with a pump) and some clamps.

3. The tank doesn't like to go in easily. You'll see what I mean. On my car, it fell right into place when I tilted the "front" of the tank up into the body, and then pushed the "back" of the tank up against the hatch.

4. Consider ordering, in advance, the high-pressure feed hose from GM. They won't have it in stock, it'll take a few days.

5. Replace the non-pressure hoses (fuel return line, charcoal canister vent line, tank vent line) with new hoses and new clamps. You can use regular fuel hose, or if you want to, get better quality "fuel injection hose". Fuel injection hose is a little more sturdy than regular fuel line (internally reinforced) but you don't need it.

6. Never run your car below a 1/4 tank of gas again.

TomP

Oh and besides, mjjmike, why would you have to cut your exhaust? Once you drop the axle down, and remove the heat sheilding above the muffler and axle, you can unbolt the intermediate pipe from the back of the catalytic convertor, and the whole exhaust slides out from the back of the car. You don't have to separate the muffler or anything.

Was your exhaust fully welded? Ouch.

rezinn

I'd agree cutting the floor sounds like a hack job, but it could be done well. Taking the time to fix what you've cut up would take a good amount of work though, so dropping the tank may not seem so bad. I'm sure it's possible to not make the lines leak by flaring them and using a good amount of hose clamps on some fi hose between them. I had a similar setup elsewhere that was good for over a year before I replaced it just for the sake of having a solid line instead. I'm sure it would have lasted much longer without leaks.

Kevin Johnson

Yes, I am swaying more to the idea of making an access hole but doing a nice and safe job of it. Hey, let's not kid ourselves and over-rationalize corporate frugality. GM saved some bucks by not making the pump accessible through the floor and they generated some extra book hours for their service departments. A win-win for them but maybe not for the DIY'er.

Volvo and BMW, for example, both have access to their fuel pumps via the floor. Both of those cars have excellent engineering. And, yes, both are usually more expensive than Chevys.

BMW pic below:

1982chevycamaroz28

at the first F-body nationals at Englishtown, there was a guy there that cut the spot where the fuel pump is and left it that way becuz one of the tubes which one i forgot but it would keep on popin off so he just cut open the floor and left it like that and just put the carpet back over.

LT1guy

iTrader: (1)

I still wouldn't do it. I have never had a pump go bad, other than a factory one with a bunch of miles...maybe because I generally use AC Delco pumps. If anybody did a truly clean job, it wouldn't be that bad, but a truly clean job would take longer than dropping the rearend and changing the pump in the first place. Plus, good luck at resale if somebody checks. I wouldn't buy a car with "shortcuts" like that; it makes you wonder what else the owner ghetto rigged. Besides, by the third time you should be pretty good at it!

LT1guy

iTrader: (1)

If he hadn't fubar'ed the lines with this "time saving modification". that wouldn't be necessary. I have never heard of factory lines coming off by themselves.

LT1guy

iTrader: (1)

Having not worked on those cars before, I would say that they probably made the lines disconnect (properly) closer to the pump to facilitate removal...that would be ok, but the GM lines have to be cut and clamped, which just gives you one more area to have a problem. You could replumb with AN and use quick disconnect type fittings, but if you're spending the bucks to do that you're probably running a cell anyway, and need more than an in-tank pump.

FJK

Hey Tom P.
EXCELLENT point on the exhaust system. Sometimes we all miss the obvious. Without having to cut the exhaust, tank removal is just nut & bolt work. Thanks for the tip.
Regards, FJK

ghettocruiser

iTrader: (4)

hey everyone. i have an 87 TA that might just need a new fuel pump. im definetly in favor of dropping the tank...but im just alittle nervous about dropping all the other stuff down. does anyone know where i can find an in depth article on doing the job??? really all i need to know is what needs to be disconnected? ladder bar? driveshaft? stuff like that. lemme know. this thread has been helpful. thanks
justin

laiky

in the true hotrodding spirit, why don't you drop your tank, locate the whole you would need precisely, making sure you could get the fuel lines out without a problem ( maybe you could swap in steel braid!!) cut the whole without the tank in place ( for safety) then get a flanging tool from somwhere like eastwood and make a recessed access panel that screws in place of if your really cool use zeus fasteners. I can't justify cutting a 3 sided hole so i could bend it back and silicone it. if you going to modify it do some work you can be proud of!

89 Iroc Z

What is this?? What is the part number?? I am putting a new fuel pump in, in a couple weeks.

Z288Iroc

The previous owner of my 91'Z cut a panel in the floor, I was pissed when the mechanic found it and showed me. I already new that he replaced the fuel pump but I didnt know he did it this way. I got a friend to patch it up and seal it really good for me, looks clean cut now but it still sucks nowing that the car you just got has a whole in it. Also my fuel guage dosent work, could he have done something to the lines and not put it back right???

FyreLance

Maybe screwed up/bent the sending unit

Kevin Johnson

The whole topic of un-molested cars and the right versus wrong way to do something is a big one.

About 1 1/2 years ago I was working on restoring a Lotus Europa S1a for a gentleman. In case you don't know, the S1a has a fiberglass shell with the back-bone frame bonded to it internally. This allows for (relatively) good strength and a nice aerodynamic fairing for the entire length of the car bottom. But, whenever you damage the frame -- which is very easy to do -- you need to cut out the bottom of the car to remove it. There are alternate methods as well, but they all involve very serious surgery to the fiberglass and a great deal of time and money.

Interestingly, the S2 and Twin Cam Europas were re-engineered and had the bottom of the car left open so that the frame could be unbolted and dropped out (or body lifted off).

I spent a substantial amount of time patching various access holes that had been (poorly) made over the years and simply left open. Making the holes greatly simplified various operations like rear control arm bushing replacement which might otherwise require pulling the motor and transmission -- and then *still* involve quite a bit of contortion on the part of the mechanic. So, I could well understand why they had been made.

There are some S1's that have had the frame removed and the complete underfairing restored -- as I said, very expensive and time-consuming undertaking. There are some S1's that have the entire fairing cut away and are essentially like the later S2 or Twin Cam. And there are S1's that have had various access holes made over the years.

Certain buyers will highly value originality -- and doing things strictly by the book (and with the Lotus they'd better have a very healthy bank account or a lot of time on their hands). Others will appreciate modifications that were well thought out and executed by previous owners. There is certainly room for both sorts of owners in the world.

ghettocruiser

iTrader: (4)

Here ya go...i found this pic of a fuel pump swap...I dont think taking the axel all the way out is necessary...but if you cant get it way off the ground it might have to be done. Just something I found.

Rage13

gotta love low tech, i replaced my mechanical pump all it took was about $15, 4 bolts, 2 hoses, and about 20 min as for cuting a hole in your car thats a big :nono: , there are reasons they didn't make a little hatch there... for safty they must have 2 seperate areas for the fuel tank and the passenger compartment, ex. why drag cars with trunk mounted cells MUST have a solid barrier behind the rear seats..
and as for an easyer fix, why not install an inline pump?

3.8TransAM

dont be a hillbilly and cut holes in the floor :-( anyhow gas smells suck inside the car (stock these cars are prone to it and exhaust creeping in so i ouwldnt add anymore holes)

did my fuel pump on my gta at work(on a lift) took my friend with me, we started at 8am and we were on the ground running at noon....We didnt even try to accomplish it fast and just took our time, stopped for drinks, smokes, the whole 9 yards lol

u dont need to drop the whole rear just unod the brake line clips and drop the shocks, sway bar connectors, and the exhuast and swing it down as fas as u dare and then drop the tank......

hardest part of the job for anyone thats done it more than once is still getting the angle to drop the filler neck out and then getting it back inot the body opening..........

so why cut holes? not the right way or the safest way by far, so just do it right

Kevin Johnson

I agree that the hole should be made safely and covered/sealed properly. If you are hesitant about your ability to do this and create a leak-free connection with the hard lines then drop the tank. Simple enough.

Here are some of the auto manufacturers that have had the foresight to install access covers for their in-tank pumps:

Volvo
BMW
Mitsubishi
Nissan
Saab
VW

Here is another pic of an access cover, this time in a Stealth. Notice the nice connectors to the hard lines:

Kevin Johnson

Here is a link from someone who installed an access cover in his Bronco. I read many other accounts from off-road enthusiasts who recommend doing it in order to avoid spending all day on the trail trying to accomplish what 15 minutes does otherwise. Food for thought.

http://www.homestead.com/90bronco/fuelpump.html

Kevin Johnson

Someone mentioned racing rules and safety, I think.

Here is a typical entry addressing fuel cells and access holes; note especially the bit about interior sheet metal:

http://www.speedwaytech.com/rulesmod.htm

FUEL CELL - Fuel cell required with the container made of steel (not less than 22 gauge steel), must be located behind the rear axle and as far forward as possible and maintain a ground clearance of 6 inches. The maximum fuel capacity, including filter spout shall be 24 gallons. The use of a commercially manufactured fuel cell is mandatory. Interior sheet metal must allow access to top of fuel cell for inspection. Fire wall of steel not less than 22-gauge thickness must be located between trunk and drivers compartment.