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Discussion Starter #1
Has anyone cut an access door into their trunk floor for quick access to the fuel pump/sending unit? Pics?

My fuel pump/sending unit seems to be operating just fine, but now has probably 15 years of fairly hard usage after the last replacement. I always keep the tank over 1/4 full, and typically 3/4 to 4/4 for all the track time to keep the pump submerged and keep from fuel starving at high cornering loads. We did replace a melted harness connector at last pump install all that time ago --- melted before I knew about keeping the tank over 1/4.

I would love to have a spare pump+sending unit on hand to take to the track in my spares bin as well, if anyone has any recommendations? This is just as much for keeping me from being stranded the long 8+ hour occasional highway trips to whatever track.

AcDelco unit looks to be out of stock at RockAuto at the moment, but I may try to source elsewhere:


Would that guy be a simple plug and play affair? Any other tips/tricks or things I'm forgetting about the job or would help make it quick and easy on the side of the highway or in the paddock at the track?

Thanks!
 

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Don't bother. The tank/sender/wiring is so close to the trunk floor that you'll slice something you don't want to. It's so easy to drop the tank. One wiring clip, two bolts on the filler neck, two nuts on the straps, and three fuel/vapour connections and down it comes.
 

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Discussion Starter #3
Don't bother. The tank/sender/wiring is so close to the trunk floor that you'll slice something you don't want to. It's so easy to drop the tank. One wiring clip, two bolts on the filler neck, two nuts on the straps, and three fuel/vapour connections and down it comes.
I'm totally fine dropping the tank in the garage to cut the access panel to avoid cutting or nicking anything, but would really rather not have to wrestle a FULL tank by myself on the side of the highway when the car is all loaded with track junk or in the paddock when track time is basically $1/minute.

I have a body mount pad on the body side in the trunk area that got a lil rusty and shredded to bits with the track use that will require chopping the trunk floor up, welding and fabrication anyway, and I figure it'd be a good time to check off both projects on my fabricator buddie's lift.

Unless some of the other connections would be difficult to disconnect through an access panel on a little hinge?

Since I plan on dropping the tank to cut the panel, I'd imagine I can make the panel cut whatever size would be necessary to facilitate fairly easy removal of all the sending unit connections?
 

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These are specific notes on my 95 Caprice wagon, from the 103 pound, 68 yr old woman who did it. Yes, a good floor jack and good jack stands help a lot. Also, WEAR YOUR SAFETY GOGGLES.
1) Remove heat shields.
2) I could tell that my "professional mechanic" (meaning the shop I trusted and paid money to) disconnected the fuel filler and vent from the fuel orifice. But, I did not have the ability to maneuver that he did, and I had to remove the hoses from the tank proper.
3) It's obvious that the straps are meant to be removed from the "front". And same mechanic had actually used anti-seize on the bolts! It looks like the rear bolts have never been touched, but who cares? They could easily be cut and replaced if they turn out to be as ugly as they look.
4) Remind newbies like me that you need to slide the rubber "boots" off the fuel line connectors before using the QD tool. And, the cheapo Harbor Freight tool worked fine. Also, realize that there will be a little gasoline gush when you pull the lines apart.
5) The wiring disconnects back by the rear bumper, NOT at the tank.
6) If you remove a wheel, it is easy to slide the tank out from under the side of the car.
7) Getting the tank back in will be a challenge, and if I come up with anything that I like, I will post.
"5) The wiring disconnects back by the rear bumper, NOT at the tank."
 

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I've replaced one pump in 25 years. The hole in trunk would have to be huge to clear the lines.
 

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Creds always given for pre=planning to streamline repairs, especially given race considerations. BUT, and yes a big BUT in this case. To start with, what I've read (and experienced with several pump replacements) is that the last 2 paragraphs of your own initial post make this a non-optimal mod. The hardlines are so long and at such rt. angle direction that the opening will end up inordinately large, and nearly 1/2 the trunk will require unloading anyway (on the side of the hiway) to get to it.

I share the posters' takes above. If the current replaced pump is a reliability concern, simply swap it out now and sleep easy another 15 years. Spectra has a rep as pretty reliable. The Airtex slightly heavier wiring harness is a good upgrade, and most guys pop for a new sender while already inside. Soldering all the connections answers the burnt wiring issues.
 
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OP

Once you get the tank out to accurately mark the trunk pan where it would need to be cut you will see its a huge cut. Doable but IMHO you would need to weld edgings around the cut hole (1/2"wide flat stock) to regain the rigidity and then add material to the cut off piece as a overlapping finished edge that would secure with attached fasteners to the perimeter of the trunk pan. This is going to be a huge "access plate" given where the pump is in the tank and the shape of the trunk pan...not some round hole on some other cars that actually come with one.

I have been towed from the track twice. Part of the $ for playing hard with a car. AAA.
 

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It has been looked at many time, and the general consensus is that it just isn't worth it....
 
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Discussion Starter #10 (Edited)
How often do you expect to replace the pump?
Once or twice, in the pouring rain, on the side of the highway, in the freezing rain, at 3am on a Tuesday. Uphill, both ways no less. Haha.

I'm just kidding around, and I understand where you guys are coming from, BUT I do hate replacing things that are still working fine, and I also don't like the idea of swapping something in that isn't "tested". I know I could probably just install a fresh one and not likely worry about it as long as the car lives, and keep the existing one for a spare, but in the off chance the new guy fails, I still gotta get back in there to swap them...... you guessed it, by myself, 4am, upsidedown in the pouring rain, on a bed of nails.

How "huge" would you say the cut would have to be for anybody familiar? I'll snap a pic of my trunk floor and maybe you guys could MS Paint a rough outline for me? I do need and use the trunk space, so if it can't figure it out without that flap or panel still sealing ok and being semi-structural, the plan is moot.
 

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Discussion Starter #11
I have been towed from the track twice. Part of the $ for playing hard with a car. AAA.
No kidding. 15 years AAA Premier member, only had to use it once for a tow from the track when I still lived out in CA. OE 4L60E burnt up halfway through the 2nd session, despite double coolers and a temp gauge. T56'd and never looked back. Had to use the AAA on average once a year for other cars, or for the race car dying on a drive home from work, etc.
 

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That's what AAA is for.... Get AAA Plus if it eases your fears of being stranded far from home.
 

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The access panel would extend from roughly the middle to the forward edge of the trunk. The vent and fuel hardlines on the sender reach almost all the way to forward edge of the tank just behind the axle. If you replaced the lines you could probably fab/mod your sending unit to use bulkhead fittings and extend the fuel line connections to the top of the plate. This would make the required access hole much smaller.

I've fabbed new plastic lines for my car so they could be made longer and the hard lines made shorter.

-Brian
 

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How "huge" would you say the cut would have to be for anybody familiar?
There was a pic on this forum years ago or at least a outline showing how big the hole is. IIRC it involves most of the forward part of trunk and about 1/4-1/2 of the flat part on the DS. Its a big cut. Not like F body

Modifications to the hard line from tank to lines running to engine would reduce this hole size

If you drop your tank you could re-route the line connection to as close as possible to the pump itself. The hole in tank is about 5"-6"...although there is not much space between tank & trunk floor pan
 

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I used to wrench in the era these cars were still in their prime. The tanks are relatively easy to drop compared to many. I saw a few people cut a hole in the floor on Camaros which is quite a bit more challenging. Either way, I think its a travesty to cut a hole in any car that isn't supposed to be there.
 

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This is the hole I angrily cut in my floor (Wagon) when I had to pull the pump for the third time in a week. **** the Delphi sending unit by the way.

It is big and it is ugly but the alternative was setting the car on fire and reporting it stolen.




I don't recommend anyone do this to their car by the way.
 

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After dropping a couple of tanks, the idea of cutting an access hole seems silly to me.

It's not like they built the car around the fuel pump.
 

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Discussion Starter #18
This is the hole I angrily cut in my floor (Wagon) when I had to pull the pump for the third time in a week. **** the Delphi sending unit by the way.

It is big and it is ugly but the alternative was setting the car on fire and reporting it stolen.




I don't recommend anyone do this to their car by the way.
I'm sorry to hear about your troubles, but appreciate your solution, haha. Didn't know the tank was in a different spot for the wagon. Guessing it must be a different tank too?
 

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Discussion Starter #19
FWIW, this is concerning my less than cherry '95 9c1 track car, so it's not like I'm hacking up a pristine SS or some kind of clean cruiser/daily. I don't have a pic of the interior, but it's gutted, save for a 4pt cage and some race seats, if that helps anyone sleep at night.
196782


If anybody is feeling handy in MS Paint and would go through the trouble of drawing me a rough outline of how the hole might have to look WITHOUT modifying the stock setup at all, I'd be grateful! Here is a pic of my trunk:
196784
 

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Didn't know the tank was in a different spot for the wagon. Guessing it must be a different tank too?
23 gallon sedan tanks are absolutely different from 21 gallon wagon tanks, and not only due to the different fuel filler necks.
 
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