Gas Tank Question

[thekents470]

I just pulled a 1975 50 gallon alum. tank out of a freshwater boat I just bought to restore. Removed the 15 gallons of gas that was sitting in it. From the outside it looks good. Is there any other tests I should perform? What or how do you rinse/clean a tank?

Thanks for your help.

[blitzen]

I would pressure test it. Years ago we pulled a 300 gal. aluminum out of a boat that would only leak when it was full. Turned out that the bottom of the tank had turned into Swiss cheese at a microscopic level.

[thekents470]

Is this something I can do?

[baitkiller]

Yes, you can pressure test it yourself but be very careful. A radiator shop has all the tools and experience as well. That is likely the safest option.

I have cleaned them with laundry detergent and water.

For home pressure testing plug off the vent and withdrawal fittings.

Use a small piece of bicycle inner tube stretched over the fill pipe and knotted off with the Schroeder valve in between.
3 lbs is max pressure. exceed that at great peril.

Good luck.

[thekents470]

OK a radiator shop sounds good to me.

[Kamper]

Just a thought... You might want to clean the gas residue from the tank before presure testing it. Steaming would probably be the easiest for a tank that size.

Otherwise pressurize it with inert gas like carbon monoxide or nitrogen that is available at welding and auto supply stores. CO2 from a fire extinguisher or helium from a party shop should be safe as well. Some folks here have said it is safe to weld a gas tank if you fill it with engine exhaust. If you do that and use regular air, or inert gas to over-pressurize it, it would still be safer than just pumping it up.

If you ust use air be very careful with grounding and to avoid static.

Pardon my paranoia!

[flying fish]

Thekents470: How much would a new 50 gallon tank cost? Does a 32-year-old tank really owe you anything?

FF