OLD GAS from 2008 in a Yamaha 150

2008 while on Deployment my dad use Sta-Bil in tank for winter lay-up . 2009 Boat was not run. May 2010 Boat started with first crank ran 5 minutes then stopped. Replaced Sierra 18-7866 fuel separator.. add one can of SEAFOAM. Local Mech suggested top off tank and run boat 30 -60 until old gas is gone. Yesterday boat started fine ran for 5 minutes and stopped. OUCH... pull fuel separator again Ran three cyles of changing sierra filter with fresh gas and boat still will not run for more than five minutes with out stall. So were do I go from here ? Keep cyling separtors with old gas until she runs ? Drain the Tank ( 70 Gallons) ?? Where do I go from here ? Get a match. Thank you for any suggestions

Re: OLD GAS from 2008 in a Yamaha 150

ditch the fuel. its bad and no amount of snake oil can fix it.
post the model number as there are at least 10 versions of a yamaha 150.