72 demon
So I clogged two electric fuelpumps, and two mechanical. I started out running a dirty tank and when it clogged my first mech. pump I pulled the sender while looking for the problem, when I put it back it leaked and I never fixed it, making it impossible to put more than 3 or 4 gallons in at a time without dripping out on the ground, making the gas always dirty dregs at the bottom of the tank. The sediment comes thru the lines as a mixture of coffee grind looking bits and fine rust powder that dissolves and then recollects in my float needle seats after going thru 2 filters. I finally bit the bullet and went to the store and ordered a new tank.

The tank is from Advance, and I got them down on the price with a printed quote from rockauto- they do the pricematching thing. It finally showed up today. It is plain galvanized and made in canada. There is no brand name. Anybody know who makes canadian gastanks?

It looks like a straightforward job, but I know there are probably people here that have made this two hour job into a two day job and can warn me away from problems. I plan to remove the filler, cut the straps, remove the sender, trash the old tank, weld up the trunk floor with some patches (a couple small problem spots- center of spare tire, and right side near tank strap hardware bracket- it would make me feel better about welding if the tank was off!), then install the new tank with the old sender and upper insulation (if there is any?) and new straps.

Wish me luck.

Radar

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madam im adam

There is upper insulation at the top of the tank. It is for noise control. You can get new replacement stuff from Year One, or simply do as I did and cut up strips of inner tube and glue them to the top of the tank. If you have any ideas of going EFI eventually, you might want to weld in a bung for a return line now. Then cap it until you are ready.

If it does not have a vent line, you could put a bung in the upper corner for a vent as well. I know the stock tanks have a complex baffling system around that vent in some cases, but mine does not have any internal baffling, and it works fine.

While you are at it, clean your lines as well. I think it was Pierre who blew carb cleaner and compressed air through his, and got them clean in that way. If it were me, and had all the problems you have had, I would replace the fuel lines as well. I would order a new gasket for the filler neck to tank. Those old parts get hard, and don' seal very well. I did not do this, and wish I had. Just be carefull and seal up you gauge well with a new gasket and sealer.

Sam

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The job is really easy and will require the use of a flat ratchet as the tank strap bolt (which are specialzed bolts with a bend in them, if you replace the spare tire pan, you'll have to go to a shop and make a set of hangers since the pan isn't equipped with these...).

Just wire brush the threads and prep with PB blaster for 24 hours before the operation, then un bolt, you will find it will make things easier in the long run, just cutting the straps will not reveal if you need to get a set of bolts from the junkyard if you can't get them off by hand first. Make sure to run the tank down so it is lighter to remove and use a jack if it has gas in it (it'll be heavy). Once the straps are off and you can tilt the tank at an angle it should just slide off the filler neck if you jacked the rearend high enough (don't forget to the remove the thoses and ground strap from the sending unit, and any other hoses (like the vapor return line if so equipped).

If removing the filler neck (for either maintenance or because you can't get the car high enough to remove the tank. make sure you check the rubber gasket in the trunk that holds the filler neck as it passes through the trunk floor, the screws that hold it in usually rust and you'll have to drill the heads off, remove the part, then redrill the screw holes and install new screws when replacing (cobalt or titamnium nitride bits are best).


-D.idiot

I am lucky my filler and filler gaskets come on and off easily.

The tire pan is only just started to rust through in a couple spots. There is a 1/4" hole where the spare holddown bracket is (the middle) and a stripe inboard the right side tank hanger bracket. I gotta clean up to good metal, but I think I can do small patches. Those bent bolts have me a little worried- I tried to unscrew them in the first place but they were bending the brackets more than they were unscrewing. They are corroded and undercoated. I figured that they could be worked better with a propane torch to loosen them up then use vicegrips and a box wrench. I wanted to take the tank off before I fired up the torch.

I looked closer at the straps, and I don't think I can cut them with tinsnips. I guess a hand hacksaw would shoot way less sparks than an angle grinder. Maybe I'll see if a cup shaped wirebrush on an electric drill followed by penetrating oil soakings will coax the nuts loose without open flame. I think the undercoating is worse than the corroson. maybe I can get a die on there to clean up most of the threads.

I decided to glue my tank sender shut and buy another one, since it has no float or sock and I don't know where to get them. That should let me fill up my tank less often and stop constantly running dirty dregs while I properly prepare my new tank.

I am thinking that even though it is galvanized I should paint it with a durable finish, and carefully insulate the top like you said, maybe some epoxy or construction adhesive holding a bunch of bicycle innertubes with the nipples cut off? I also think it might be smart to insulate the straps from the tank to prevent rust? Are there any static electricity considerations? Should the tank be grounded to the body?

By the time I can spend another seventy on a sender I should have the tank ready to go.

thanks again

radar

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madam im adam

I covered the top of my new fuel tank with ice and water shield (bituthane), right down to the crimped edge. I noticed the old tank was fine under the old insulation mentioned by Sam Powell, but rusted all around it. Have not time-tested setup yet.