Assembly, fuel tank, diesel, large;next assy 12505663;used on fmtva1p2;fuel tank components which are not welded to the fuel tank vessel shall meet the requirements for a 48-hour salt spray 1aw astm b117;fuel tank shall have all ports closed and sumerged in a tank of water with 7-10 lbs of air pressure for 5 minutes. There shall be no evidence of air leakage from the submerged tank in the 5 minutes. Any evidence of leakage will constitute a failure. An optional method is the use of a leak detection compound in accordance with mil-prf-25567;production quality control test: a. Test on unit every 50 unit/lot to assure control of the part