Gas tank, Repair or Replace?

Dsertdog

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As some you have read on Polaras project thread, I'm having a problem with dirty gas.
The tank needs be removed and cleaned or replaced.
In addition to the old gas, the stock tank has a soft ball sized dent on the driver's side.
The sender seems to work fine.
A new tank is about 4 bills with freight. I figured a new float and sock along with gaskets and a tank to trunk gasket too.
Thoughts? Opinions?
Thanks
 
400? I don’t think I paid that much all together but maybe.

Honestly, I went the clean out route and it just didn’t work out. I’d suggest just replacing it.

Just make sure you use the stock lock ring. The new ones are chintzy and don’t lock well. Mine jumped out .... aaaand that was the 5th and last time I intend to drop my gas tank for some time.
 
If it's not rusted, just flush it, and put in the new float and sock. While you have the tank off, backflush the line from the carb with some good solvent, and put a new filter on.


Unless money isn't an important part of the equation, in which case, just buy a new one.
 
If it's not rusted, just flush it, and put in the new float and sock. While you have the tank off, backflush the line from the carb with some good solvent, and put a new filter on.


Unless money isn't an important part of the equation, in which case, just buy a new one.
This is also true if it's not corroded I was just assuming it was.
 
My rule of thumb when it comes to gas tanks is: if they make a new one, replace it. This was told to me by a radiator shop owner 30 years ago.

On these tanks with vent lines, the lines often become plugged solid with rust and can't be cleaned out, plus if you introduce sealer to the inside, then they will surely be plugged.
 
It depends on what you mean by dirty fuel. If you are clogging fuel filters with rust, the tank needs to be replaced. What usually happens is that a car is left with moonshine blend fuel in the tank for a period of time and the fuel breaks down to form a corrosive by product that eats up all the plating on the inside of the tank. Once a tank starts to rust, there is no good fix, it will continue to rust. You can pull the tank and remove the sending unit and check the inside of the tank for rust. If it is rusty, it belongs on the junk pile and do not give it a second thought.

Dave
 
Picture's worth a thousand words right? This is filter number 3 or 4 within the last month.
000_0009.JPG
 
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Prices vary on C-body fuel tanks. Although they all probably come from the same factory. So DO shop, but Van's is typically the most cost effective to purchase. Not sure if the new sending units are the correct ohmage? Cleaning the old one might be a better option. Which could also ensure it matches what the fuel gauge on the instrument panel needs.

CBODY67
 
Does it matter if the tank comes vented or non-vented? Some sources sell an non vented tank for 66, Van's shows vents, probably why it works on a 67 and up C body. I can plug the vents.
 
It looks like rust scale...I would attempt to wash it out with metal prep...that should remove most if not all the rust...and agree with back flushing the lines.
 
I always try saving them, for the sake of originality and cost savings. My '70 Newport convertible was sitting for twenty years (with a few yearly firings and the odd jerry can thrown in). It's fuel looked just like yours. I didn't remove the tank just the sender, sucked out all I could, back flushed the line, replaced old sender, new filter (clear one), filled 1/4 tank. Drive with sloshing in mind, lots of hard starts, stops and corners, hit some train tracks for good measure, inspect and replace filter when needed. Keep filling quarter tank at a time. I went through about three filters in 300 miles. Once it was running clear for a few hundred more miles, I replaced the sender, all hoses, pump and filter (steel one). That was 5-6 thousand miles ago. Every scenario is different. It worked for me, but it could have been an exercise in futility. I usually do things the hard way though, family trait. Should have mentioned, when I replaced the steel filter 3000 miles later there wasn't any signs of rust!
 
Prices vary on C-body fuel tanks. Although they all probably come from the same factory. So DO shop, but Van's is typically the most cost effective to purchase. Not sure if the new sending units are the correct ohmage? Cleaning the old one might be a better option. Which could also ensure it matches what the fuel gauge on the instrument panel needs.

CBODY67

So far Vans was the cheapest. An exact non vented tank is more, but I can plug the vents. Car isn't totally numbers matching and I'm a stickler for reliability.
 
When swapping or removing the tank, be SURE to remember that the clamp which goes from the body fuel line and the sending unit grounds the sender. Clamp with a bar between the clamps which touches the body fuel line and the sender output tube. Normal Chrysler stuff from back then, I suspect.

The 4-tube version is for the evap emissions control system. 2-tube would be the normal version with the vent pipe which goes high onto the rear frame rea. No-tubes would need a vented gas cap, I suspect.

Just some thoughts,
CBODY67
 
So far Vans was the cheapest. An exact non vented tank is more, but I can plug the vents. Car isn't totally numbers matching and I'm a stickler for reliability.

My '66 Chrysler convertible has a gas tank with two vents (I think), so your car probably has a vented tank too. DO NOT PLUG THE VENTS.
 
So far Vans was the cheapest. An exact non vented tank is more, but I can plug the vents. Car isn't totally numbers matching and I'm a stickler for reliability.

Have you pulled the tank yet? I'd be surprised if you didn't have a 2 vent unit.
I'd drop the tank, get a direct replacement and a new sending unit and flush your lines really well ... esp seeing that fuel filter.

As I stated before, don't use the lock ring in the sender unit kit, it's crap.
 
Does it matter if the tank comes vented or non-vented? Some sources sell an non vented tank for 66, Van's shows vents, probably why it works on a 67 and up C body. I can plug the vents.
There's two vents on the tank, so the vents are correct.
 
After discussing it with my lady, she agrees that a rusted tank is unreliable and a dented tank is undesirable. Unreliable +undesirable=unuseable.
So I'll be ordering a tank and hardware from Vans this week.
Thanks to all who responded.
 
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