Write up on how to drop your tank.

Moderators, we don't have a how to or tech tip section so I'm putting it here.  maybe we should add such a section? or make a sticky?

Seeing how I've dropped tanks at LEAST 6 times since January Chris suggested I write it up.
I thought about some pictures but really I don't thin they are that necessary as it's pretty straight forward.  I will be as detailed as possible.

Symptoms that your fuel pump is on the fritz

1. Car won't start and/or no nice 'cone' of fuel spraying from the TBI.
2. Car starts and surges at idle and stalls when in gear on runs horribly.
3. fuel filter replace has no positive effect (hey you needed to change it anyway).

The tank drop is the same for all years/models.

Prior to the drop I verified that I was getting proper voltage at the harness connector below the DS tail light.
I also swapped out the fuel filter.  I tested the key on 2 second method into a bucket at the fuel filter and it 'seemed' okay, but looking at the fuel spray cone at the TB told the truth ( not enough fuel).  After the last episode where I changed/rebuilt just about everything else it was fuel delivery that was the issue.

1.  Disconnect the battery

2.  Jack up the car or use a lift.  ( put the car up enough to get a creeper under it and with it close to the ground I can put a floor jack and piece of plywood under the tank which is really nice.

3.  If you live up north spray it down with PB Blaster the day before.

4.  Remove the heat shield on the front of the tank.  Three 7mm bolts.  You can leave the side shield9s) on it's not in the way.

5.  While you are under there reach up and hook the clasp holding the fuel lines up.

6.  Disconnect wiring harness and release the wire loom so it hangs down.

7.  If the tank is full (like mine today)  siphon out as much as you can ( I only got about 6 gal out).

8.  Loosen the three clamps on the filler neck (if tank is full it'll start to leak so put a coffee can under it or wait until later for this
step.

9   Use two 13mm or 1/2 inch wrenches  on the back strap mounts.(I used 13 mm up until today where the nuts were rusty and I used 1/2 inch on the nut side, then vise grips when that one rounded too).  PB Blaster is your friend

10. Remove the nuts but leave the bolts in place.

11. Use a 15mm and break loose the front bolts that hold the straps up.

12. Use the floor jack and piece of plywood to support the tank.  Just enough to support the weight of the tank but not raise it.

13. Remove the front 15mm bolts.

14. Slowly lower the jack (not all the way) until you have enough clearance to get at the three fuel lines.  one you need gas/slip joint pliers to squeeze the clamp and slide it back, the other two are the quick disconnects.  You can either use the cool little tools or a pair of pliers to squeeze the ends and pop them off.  If there is still pressure some gas will squirt out.

15.  Once you have the three lines clear start working on the filler neck hoses.  I spin them to break them loose then wiggle them off.  You may need to adjust the jack to do this.

16.   Again using the jack adjust the tank height to allow you to just slide the bolts out on the rear of the straps.

17.  At this point the tank is free.  Lower the jack (a helper is key here) to steady the tank), and slowly slide it out from under the car.

18. Vacuum  or blow off the top off the tank as you don't want alot of crap getting inside.

19.  10mm socket and spin off the nuts.  slowly remove the sending unit. you have to change directions a couple times to get it out, just pay attention so you know how to put it back in again!

20. Inspect that  little rubber hose on top of the pump, perform the Sherlock solder fix ( [You must be registered and logged in to see this link.] ), replace pump or whatever.  I couldn't replace the thick wall fuel line exactly and went with fuel line from the parts store and used standard hose clamps to attach.

21. If the tank is still pretty full siphon out some more.  I lifter onto saw horses and got another 12 gallons out leaving about 5 in the tank.  More would have been better but I ran out of gas cans.

22.  Bench test your work I used a coffee can with about 3-4 inches of gas in it and put 12 volts onto the harness wire.  I did all this outside with a breeze blowing so no fumes accumulated.

23. Reassemble tank and prepare for installation.  I cleaned up my straps with naval jelly and some  spray paint (didn't have all day to POR-15 them).

24. get your plywood on the jack then the straps and sit the tank on top.  Wheel under car and jack it up.

25. Installation is the opposite of removal.
     Slide rear bolts in first and put nuts on loosely.
     Work filler neck hoses back on and tighten
     Reattach fuel lines
     Install front bolts and tighten them up
     Attach wiring harness and snap loom guides closed
     Tighten rear nuts
     Install front heat shield.
     Reconnect battery and fire her up.
     Drop it off the stands and test drive!


Having a helper for the putting the tank into position is REALLY helpful

When I replaced my fuel tank, I found a tube inside the filler nipple on the tank. It has a ball check valve at the end of it. If you remove the insert, you can put a siphon hose in it and drain the tank. This was a tank from a 91 RMW. Other years may not have it, but I could not put a siphon hose in it with the tube in the tank.

That may be there so if the car rolls over and the fill pipe gets severed, gas doesn't come out...

.Mark the three hoses from the tank so they don't get confused when reinstalling.


..about that stinky little looped hose. Don't use the one they sell you that is a thin preshaped loop. It's not reinforced, which in my opinion is why it splits. Get about 18" of SUBMERSIBLE HIGH PRESSURE hose. Put a big loop in it, Trim to length. add make sure you use the metal screw on hose clamps. Don't use the ittle plastic crimp on retainers. The have a habit of popping off.



As long as you are in there, it's a good time to reset the resistor to make your gauge more accurate as well. Loosen the screws to get to the resistor. Lightly sand it with 800 or finer sandpaper, even a pencil eraser will work. Tweak the little brass finger so there is more pressure applied to the resistor.

Reassemble, but loosely. Take an ohm meter an attach to the resistor / finger connections. Juggle and wiggle until you are getting the lowest possible reading on the meter. Tighten it up. Your gauge will now be more accurate.m

Don't forget to put back the big rubber ring that seals top of the sender unit.

[You must be registered and logged in to see this link.]Did you guys see my fuel sender recalibrate procedure over on ISSF?

[You must be registered and logged in to see this link.]

Good call on this sticky.. i had to drop my tank three times one week.. pain but after the first time it gets easy..

i cheated,. i lowered the tank onto the ground still on the front side of the straps,. left the hoses hooked up,.pulled the sender, switched pumps, re-installed,.
If you lift the car high enough (i,m talking backhoe here) you can put a 45 gallon drum under the tank and work on it almost standing up,.

Nick

No doubt, coincidentally at the exact moment I had to get in the tank, four times...I was unfortunately out of backhoes and 45 gallon drums. No ropes or sturdy trees in sight to lynch the bastards who stole them either! DAMN I hate when that happens.

So I raised the car using a hydraulic jack centered on the tranny pumpkin and then I used a set of 5 ton jack stands to hold up the car by the chassis. I used the jack again lightly against the tank while unstapping by removing the four bolts then lowered it for repairs.. When installing it I raised it again while balanced on the jack, close to final height, and put it on a second set of stands while I re-strapped the tank. That way I could crawl between the stands to get at the tank lines and bolts.

The fun part is when you unsnap the fuel lines and get a face full of gas... Yum Yum! My favorite part of the whole adventure!

It's handy if you can borrow a body to turn the key to ON while you have your head near the tank to hear if it is running. If the pump runs but there is no pressure, figure it's a split or popped hose.

If you are alone, it can be difficult to hear if the pump is actually running from the cabin of the car. it's relatively quiet to begin with. IF you have spare battery kicking around, go to the rear of the car, pop the connector at the left rear underside coming off the top center of the tank. Run jumpers to the black (ground) and gray (+12) wires. You can hear the pump easily. as it makes a sound like a cell phone on vibrate. If you also hear a sloshing sound... then I welcome you to my wonderul wacky world of split hoses.

I agree whole heartedly with others here, that if you are in for an inch, you might as well be in for a mile (that's 2.54 centimeters and 1.375 kilometers to all our Canadian brothers) CHANGE THE FREAKING FUEL PUMP while you are there. How many miles you got on that beast anyway? It's 15-20 years old! How much longer do you think that bad boy is gonna last my friends? Suck it up and spend the green (or Loonies) and just do it!

1 mile = 1.609344 kilometres

Ooops. at least I got the other part right ! See you in about 11 days... with the Corona's!

Dave

bump for appropriate viewing

Sprocket wrote:

bump for appropriate viewing

Annnd bookmarked. Wish I didnt need to read this thou

I'm going to bump this. So my new fuel sending unit is here (yay!) and I just dropped it into the tank. As mentioned it took a bit of fiddling to get it in place. I bolted it back onto the tank but I noticed there was some play between the sending unit and the tank. Is this normal?

What do you mean by play? That sending unit should not move once its bolted back to the top of the tank...did the O ring seat right?

brokecello wrote:

What do you mean by play? That sending unit should not move once its bolted back to the top of the tank...did the O ring seat right?

Yeah, it moves a bit side to side. I'll have to check the O ring again. It did feel a bit weird when I was bolting it up.

should be snug and tight, methinks the o-ring didn't set right.

Sprocket wrote:

should be snug and tight, methinks the o-ring didn't set right.

Thanks. I'll check it tomorrow. I just cant wait to get this thing running again.

lakeffect wrote:

.Mark the three hoses from the tank so they don't get confused when reinstalling. .

Just a small note on this. On my 1993 all three hoses are different sizes. Plus one doesnt even have a quick connect so that makes id'ing easy.

Finally got around to checking the O ring. The o ring was not the right size (kit came with two different ones) swapped it out and now we're good to go. Tank is going back up on Sat. Hopefully will be on the road again.

all years have three sizes, the sending units are interchangable, but I think the LT1 pump pushes higher pressure.

Gonna move this to 'Engine' and sticky.

The other tip I would always suggest. Know that you have dropped a tank, PUT A DRAIN IN IT!


For under five bucks, Places like NAPA and Advance Auto have retro fit drains , usually fro transnission pans. BUY ONE AND PUT IT IN!

If the pump fails again, and you have a full tank of gas, you'll appreciate the ease of draining the tank by letting gravity do all the work.


Quit yer damn whining out there, and just do it!

Stupid, embarrassing bump. I can't get the float screen to attach to the sending unit. How does it go back on again? All ready to install the tank again minus that.

Do you mean the filter? The silver circle of the filter screen just gets pushed on.

If you are referring to the plastic float for the fuel gauge sender, I'd need to look at the spare in the garage first. Let me know.

lakeffect wrote:

Do you mean the filter? The silver circle of the filter screen just gets pushed on.

If you are referring to the plastic float for the fuel gauge sender, I'd need to look at the spare in the garage first. Let me know.

Yeah the plastic float. I'm having a massive brain fart as how to reattach it. That or I dropped a piece in the tank (which would be my luck...)

The float it self has two grooves on one end and a hole in the other.
You'll be using the short groove so that the float is flat in the tank, not vertical. Even though it appears that rod would be long enough to use the long groove, don't do that. A simple push on retainer holds it onto the rod.

I dont have anything like that. Just so we're talking about the same thing.... I'm talking about the beige/tan colored rectangular screen that mounts on the bottom of the sending unit.

OK that beige/tan Screen should be your strainer/filter that goes onto the bottom of the fuel pump. If it has a metal ring in the center of one side, that gerts pushed onto the bottom of the pump inlet.

Beyond that, Post a picture.

lakeffect wrote:

OK that beige/tan Screen should be your strainer/filter that goes onto the bottom of the fuel pump. If it has a metal ring in the center of one side, that gerts pushed onto the bottom of the pump inlet.

Beyond that, Post a picture.

Yep. That was it. Got it back on. Thanks!

Glad to be of help..

Happier that I didn't have to call in the sheep for help!

lakeffect wrote:

Happier that I didn't have to call in the sheep for help!

As are they......

very good write up John, got the tank out today for Gumby , now i can put all the gas, about 8 gal into the new roadie for the trip down wednesday , ill come visit while im down

Couple of things to add: The tube with the ball in it can be grabbed and pulled out with a pair of pliers to allow the bottom half of the fuel to be sucked out..... You will re-install this tube while the pump and sender are out because it has a plastic "tongue" that installs into a retainer on the side of the baffle wall on the fill tube side.....
And about the filter sock......You get one shot at installing it oriented properly and if you haven't oriented it properly, the screen assy will definitely be ruined and possibly the bottom nipple of the pump, as well......If the screen sock is longer on one side of the retainer ring, pay special attention to orient the sock on the pump so it will lay completely inside the baffle box without being kinked.... If the sock is kinked or laid up over any of the baffle walls, the system can suck air and the sock can prevent the float from dropping below 1/2 tank (I had a Caprice wagon that had this problem)
Something else I noticed absent....... The three small screws securing the top of the filler neck MUST be removed, unless you want to break the plastic mounting ring (I've found the plastic broken on three of the four cars I've done)

Replaced the fuel pump on my 1991 OCC (TBI) this morning. Excellent write up in this thread. Just wanted to add that electrical connection is remote from tank. Mine was attached to the frame at the extreme left rear corner of the frame. Do not try to disconnect the yellow connector at the top of the tank.

Prior owner must have had pump replaced because it was a no name and did not have the curly hose connection. What the heck is wrong with this fuel pump design?

the problem is that modern manufactures don't know how to properly make the part any more, as most times the original pumps last 20 to 30 years.

The pump I replaced was an Airtex E3268. I put in a Delphi kit and hope it lasts.

Walterf wrote:

The pump I replaced was an Airtex E3268.  I put in a Delphi kit and hope it lasts.

Lately the Delphis have been shipping with a fuel hose that is NOT ethanol resistant. You'll know in a thousand miles or so...several members have gotten screwed...

The good news, dropping the tank goes ALOT faster the second (3rd, 4th, 5th times...)

sometimes not even a thousand miles, didn't even have 400 on the last one in my buick that split.

But also every sending unit that has been put in has the fuel gauge off by at least an 1/8th of a tank if not more on the low side.(So the gauge is saying you only have an 1/8th of a tank left when really you have 1/4 tank left.)