I have a FL106 2001 w/series 50 Detroit. I have had it about 6 months.It had sat for awhile before i got it and would only run off the right side tank.Ran some fuel addive and took care of problem.Took two weeks of in july now back to running on right tank.It seems to be worst this time if I have to idle all night by morin it start pushing fuel out the vent tube on the left. The lines look in good shape and no kinks. Any help or advise would be most appreciated.