I have a 1995 johnson 150 , carbed , with ops ignition that may not start at all or will just quit running down the lake . Some times but most of the time give a few min. It will fire up . I do know it loses spark on all plugs when this happens . Seems to be weak coming out of the hole with a full livewell . The boat is a 17.5 ft. Hydrasport . Boat sat for 2 years . Is there a fuel presure switch ? I have tested kill and ignition switch .