i got a ohh50 tec it is running vary lean i have cleand carb 2 times made jet a lol bigger it helped some but it will idle bad and when i try to rev it will die out and slowly rev up when it does rev up it goes up and down if i pump the primer when i try to rev it will work well but i have to keep pumping primer non stop to keep the rpm up i am lost on what it could be air filter is stock ty for any tips