Lock ring repair on a steel tank?

So on my tank that I pulled off the truck last summer, I tried replacing just the sending unit, but 40 years and caked on dirt and grime rusted the hell out of the sending unit and the lock tabs for the ring. I was able to get it out, at the cost of pretty much the entire mounting mechanism for the lock ring, like it peeled off from the tank and now its just a bare tank with a little sodder(can grind down smooth, tank has been empty since august in a ventilated shed.), would fill with vinegar probably just to clean the gunk out of the gas tank and the minimal debris. That way no potential issue with sparking, even thoguh its been forever.

On plastic tanks, they sell a kit that you can screw into the tank to repair the lockring if it were to become damaged. Is this something one can do or any creative ideas to do to a steel tank? ID like to fix the tank, its really not rusted internally, just the sender was shot and the top rusted bad. But the tank is clean outside with just surface rust and inside was gunky at worst. I need a passenger tank, that one has a convenient puncture when gas was removed from it when the switching valve broke many years ago...

Id assume fix this tank up, get a new valve, and fix the wiring for the switcher and have 2 gas tanks again.

Be real careful about welding on an old gasoline tank. Something about the metal has absorbed the fuel and when you heat it, the fuel fumes are released. I'm not the pro welder but I was told by an expert welder the only safe way to weld on a used tank is to fill it with water, then weld.

Better idea might be to drill 5 small holes in the new lock ring and tank, then attach with machine screws and the little nylock nuts. Many medium duty trucks have the sender float installed this way, except the inside of the tank has a thicker ring attached to the inside for the machine screw threads.

How about a picture of this tank?

Tanks for squarebodies can be purchased as cheap as $70 online. It may be more cost effective and safer to purchase new.

^ this. You're liable to spend a lot more time and money trying to get an old one fixed and still end up buying a new one.

That's what I'd do. The part about spending all the time and money and ending up buying a new one anyway.

I got mine for 50 dollars new from amazon, only because it took a month to ship and had a broken cardboard box. But it was uncommon. Where are you seeing these tanks? And, I had to drive an hour to pick it up because the shipping company decided they couldnt deliver it. I was a little upset.

Anywho, Its not sounding like steel tanks have the repair kits then? I know plastic ones do, but thats plastic vs metal.

Turbo4whl said:

Be real careful about welding on an old gasoline tank. Something about the metal has absorbed the fuel and when you heat it, the fuel fumes are released. I'm not the pro welder but I was told by an expert welder the only safe way to weld on a used tank is to fill it with water, then weld.

Better idea might be to drill 5 small holes in the new lock ring and tank, then attach with machine screws and the little nylock nuts. Many medium duty trucks have the sender float installed this way, except the inside of the tank has a thicker ring attached to the inside for the machine screw threads.

How about a picture of this tank?

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I wasnt thinking welding, but Ill send a picture of two tanks, 1 thats been outside and hasnt rusted(no idea how) and mine. Both have no ;lock ring. The set that I mentioned for plastic tanks is a plastic retainer that you screw in that holds pressure around a sending unit for a late 90s gm car. Same lock ring system, but the material is different. Id imagine steel you need a different system.

I forgot to take a photo of the other tank. Welp. Here's mine

Heh I dont know how I ended up on this old thread, but valid question, still curious about the subject

My dad is getting serious about fixing the 75 and if the lock ring on this could be repaired easily we could put a second tank or just replace the one it has , giving it a bigger neck which would take fuel faster. The 75 neck is small and because of its flatbed its not fond of taking fuel quickly.

If its just unadviseable still, we probably would just get a newer tank and neck if we care enough. Good time to go 3 port

Imho, that tank is hashed. The time spent fooling with repairing it will outweigh the cost of a new tank.

bucket said:

Imho, that tank is hashed. The time spent fooling with repairing it will outweigh the cost of a new tank.

Click to expand...

^^^^^^^^X2 on "hashed".

bucket said:

Imho, that tank is hashed. The time spent fooling with repairing it will outweigh the cost of a new tank.

Click to expand...

i wonder what a good use for it would be, maybe install it on my garbage trailer and put sand in it. Why? uh... didnt think that far ahead