fuel tank test

[1971 sport]

i have 3 fuel tanks to choose from. what is the best way to test them to determine if they leak or not. water,air. please help.

 

[bronconut73]

i have 3 fuel tanks to choose from. what is the best way to test them to determine if they leak or not. water,air. please help.

This may sound a little redneck.
I hung my tank from a tree branch and filled it with water and watched it for awhile. Hanging it from the tree branch allowed me to see all sides and seams at once. Every once in awhile I would pressurize it with a little air from my compressor, not alot of pressure. Never leaked. One of my eb buddy's is still running it. It's probably been 10 years or more.

 

[NicksTrix]

all depends what you have to work with.

you should first check them to see if they are rusty inside. if they are KBS makes some very good tank cleaner/sealer kits that will take care of that issue along with any pin holes... www.buykbs.com

to air pressure test you will need a way to plug all the ports securely, have a gauge on one along with a way to pressurize the tank slightly and keep it pressurized to you can look it over. when i build my tanks i go up to about 5# of pressure. that is enough to get the tank to start bulging.
i prefer to pressurized the tanks full of water.
you will want to be sure to get all the water out and be sure it's dry before you use it.

if you are just worried about pin holes, i'd suggest just get the tank liner kit and use it in the best physical condition tank you have. refinish the outside and carry on.

 

[1971 sport]

Thanks for your help
Redneck or not
Lol jk. Whatever works is ok with me. I will probable do both. Water and air and line it like you suggested Nick. By the way i did sell that tub. Thanks for your info. Business will be coming your way at some point in this build.