Hindsight is 20/20

[Pawned]

From my notes of July 10

Yesterday I removed Natalie's gas tank. Once I got the gas out (very gritty gas) I cleaned 'all' the rust out. I flushed out the cleaner and the water was clear. I the took out my high pressure sprayer and went to work on it. It took 90 minutes of the sprayer until the water stopped coming out ugly brown. I put the tank back in. I now feel half way confident to put in gas and run it once I finish the engine
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So I have been working on a myriad of problems, among them are the fuel gauge not operating correctly and a filthy gas tank.
After all the cleaning of the tank, I reinstalled it and put some new gas in the car.
I messed around with the fuel gauge and could not get it working properly. She ran out of gas on my way home from a short drive. Thankfully, I listened to some of the advise I got here and kept a small gas can in the trunk.
After putting in some gas, I drove over to the gas station and filled her up and the gas can too. Lo and behold the fuel gauge is not completely dead.

I get home and put her in the garage, until my wife comes in saying the garage stinks. I go out and look and the fuel tank is leaking.

I siphoned off about 4 gallons and the leaking stopped.
I ordered a new tank from Minnesota for $119 including freight. The shops around here wanted a minimum of $150 just to look at the old tank.
New tank should be delivered tomorrow.



The pictures are from before I cleaned it initially.

 

[tekslk]

The leaks are often the clip on the sending unit, you may want to double check that.

 

[moparmat2000]

From my notes of July 10

Yesterday I removed Natalie's gas tank. Once I got the gas out (very gritty gas) I cleaned 'all' the rust out. I flushed out the cleaner and the water was clear. I the took out my high pressure sprayer and went to work on it. It took 90 minutes of the sprayer until the water stopped coming out ugly brown. I put the tank back in. I now feel half way confident to put in gas and run it once I finish the engine
----------------------------------


So I have been working on a myriad of problems, among them are the fuel gauge not operating correctly and a filthy gas tank.
After all the cleaning of the tank, I reinstalled it and put some new gas in the car.
I messed around with the fuel gauge and could not get it working properly. She ran out of gas on my way home from a short drive. Thankfully, I listened to some of the advise I got here and kept a small gas can in the trunk.
After putting in some gas, I drove over to the gas station and filled her up and the gas can too. Lo and behold the fuel gauge is not completely dead.

I get home and put her in the garage, until my wife comes in saying the garage stinks. I go out and look and the fuel tank is leaking.

I siphoned off about 4 gallons and the leaking stopped.
I ordered a new tank from Minnesota for $119 including freight. The shops around here wanted a minimum of $150 just to look at the old tank.
New tank should be delivered tomorrow.



The pictures are from before I cleaned it initially.

So tell me again why you would flush out a rusty tank and stick it back in the car when repops of this gas tank are available for about $100. If the inside is rusty its because theres no galvanizing left inside the tank to protect the steel.

I only had one tank boiled out and teflon coated on the inside before, it was something you could not get a repop for, no choice but to fix it. This tank will keep getting rusty crap in it no matter how u clean it.

 

[Pawned]

So tell me again why you would flush out a rusty tank and stick it back in the car when repops of this gas tank are available for about $100. If the inside is rusty its because theres no galvanizing left inside the tank to protect the steel.

I only had one tank boiled out and teflon coated on the inside before, it was something you could not get a repop for, no choice but to fix it. This tank will keep getting rusty crap in it no matter how u clean it.

This is the first restoration I have done. You live and you learn. I plan on making lots of mistakes but never make the same mistake twice

The leak is coming from above the new sending unit.

 

[my5thmopar]

Lets see....you used the shiny new lock ring that came with the new sending unit? Many here have made that mistake. Either bend the tabs or use the old thicker ring. Probably better with a new tank anyway. Good luck with it.

 

[72Dodge]

Most likely what my5thmopar said (but check the sensor hardware also for a leak as mentioned above). When I installed my new tank, I used the old clip ring with the new gasket and made extra sure that it was installed straight and centered, and I have no leak with the tank sitting full. There is a sending unit lock ring tool (Vans Auto has it, or other places) that isn't necessary, but sure does work great for removal of the old one and installation of the new one. It's like 12 bucks. I sprung for it and didn't regret it because it made short work of it. Good luck!

EDIT: And make sure you get the ground strap back on. If you need a new one, watch out for the ones usually sold, like by Vans... it's too short and won't work. Do a search here and read about different solutions, but it's pretty easy to just make something that will work.

 

[Pawned]

I have the tank in but have odds and ends to do, because it got too dark

I installed the sending unit took a bunch of time to get it seated correctly.

After reading the replies above, I have a feeling that I did not secure the clamp on the old tank's new sending unit correctly. I am not sure it leaked there but it was not properly installed and would eventually be a problem.
When I cleaned the original tank I figured I would have to replace it sooner or later.
Well, it turned out to be sooner. Still according to plan.
I really appreciate the informative feedback

 

[Pawned]

The video is only 13 or 14 seconds long.
curiouser and curiouser

 

[Pawned]

forget it. can't upload a video

 

[burdar]

If you continue to have sending unit issues, I'd reinstall the original unit. Buy a gallon of EvapoRust and soak the sender in that for a couple days. I bet it comes out looking new and will probably work better then a new one.

 

[jos51700]

How was the calibration on your new sending unit?

 

[Pawned]

I have fixed the gas tank problem a couple weeks ago, I think.
I did fix the problem with the bad fuel gauge. I am able to calibrate the fuel to a certain level, but I need to run it out of gas to set the empty level. I do not care what it reads as long as it reads empty when the tank is empty.
as promised I will put out the complete specs on my modification. Parts cost me a whopping, actually I do not remember but I think it was below $5.

You need a 100 ohm or less adjustable multi-turn resistor/rheostat/potentiometer all will work the same but for precise adjusting it much be multi turn LOW resistance
. My has 24 turns from 100 to zero.
more to come after I run the tank dry

 

[Pawned]

If you continue to have sending unit issues, I'd reinstall the original unit. Buy a gallon of EvapoRust and soak the sender in that for a couple days. I bet it comes out looking new and will probably work better then a new one.

Burdar: I do not think it possible that the original sending unit would do the trick. In the picture, that I am hoping will upload, I am sure you can tell which one is new and which one it the original. The originals resistor has been eaten away and so does the wiper arms connection pin.

 

[burdar]

My original Challenger sending unit looked really nasty so I replaced it. With all the trouble people have been having with the new ones I was curious what my original one looked like inside. It looked almost brand new inside the cover. It had stopped working because the pin that makes contact with the resistor was worn. I bent the contact slightly so it touched the resistor again. That and an EvapoRust soak is all it would take to make mine useable again. Your experience may differ.

I've heard that an extra ground wire soldered to the main body and the float arm helps to make the new ones more accurate.

 

[Pawned]

My contact that touches the resistor was non-existent. I did add an extra ground wire to the body to the sending unit