Welding in a bung on a steel fuel tank.

So I had an idea on this new fuel tank. Weld in a bung for a tank vent/roll over protection valve on this stock 66’ fuel tank. Fuel puking can be a real issue. So I bought this steel pipe bushing at a hardware store. It must be steel to weld to a steel tank. Please be advised this was a brand new tank and not a used tank that had fuel in it. Please never weld on a fuel tank that held fuel. The old thought of welding a tank full of water is not safe. Let a used tank sit and dry for a while after washing in hot water and soap before you try to weld on a used tank. Gasoline fumes are EXPLOSIVE!


Then I screwed in a 1/4” brass pipe fitting. It can be anything (in this case 1/4” npt or “national pipe thread) because that was the inside thread of the pipe bushing. Brass will not stick to the threads but will protect them. Once cool it screws right out.

Before I drilled with a Unibit. Trust me these work really well on thin sheet steel. I presrilled where I wanted with a 3/32” bit to keep the unibit from walking while trying to start the hole.

After fitting wire brushed off the coating with a rotary wire. I welded the two parts (tank and fitting)

After welding I pressure tested at about 2psi and soapy water. All good.
I was so pleased with the results I added a drain bung to the bottom of the tank to drain off fuel before winter rest. Before using it, vacuum the tank out with a shop vac and even wash it out to get all the metal chips out before putting the tank into action. Even give a touch up of paint.
About author
I've been a "Jesus Chrysler Nut" for over 35 years. I've built and rebuilt quite a few Dodges, Plymouths and Chryslers. I've bought and stripped more than 35 cars in my life time.

"Any one can restore one but it take a real man to cut one up."

I enjoy the hobby and realize not all fun is in the finish product but the journey. The meeting of new people also passionate for the hobby is the best part and I enjoy helping people out where ever I can. The saddest moment and the happiest moment is when a car is finished.

I was a GM Master Tech by the time I was 21 years only and was a Lead Technician with 7 mechanics under me for 10 years at the dealership level. I now own a welding and equipment repair company in SouthEastern, Connecticut for the last 22 years. When I started the equipment business I did it on the side and worked the full time technician job during the day, nights and weekend for the first few years fixing farm and construction equipment.

MoPars have been my goto for fun, relaxation, mental break and family fun now getting both my sons into this hobby. There is not one piece on a car including body work I have not tried my hand at and felt like I've been successful. I am so happy I chose not to wear a bowtie or an oval for my vehicle. There is something about following Mother MoPar.

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