personally, I would not recommend compressed air, even tho it has been the norm since the beginning of time.
I lean more towards filling with water and using a hand pump to control the internal pressure.
just like pressure testing a scuba tank – you do not want 80cf of air at 3,000 psi exploding all at once. (should failure occur).
auto repair shops use this technique with testing radiators for leaks…….. with water – not compressed air.
some bicycle pumps can reach over 100psi. a good recommendation would be the 12-volt air compressor from Harbor Freight.
it pumps slow but steady pressure up to 100 or 150psi.
if the gas tank ruptures when filled with water, very little chance you will be hurt .
if the tank ruptures when filled with compressed air, very good chance you could get hurt – badly.
the tire valve can still be used to connect a hand pump to after filling with water then pressureize it accordingly.
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