I don't get it. What is the trick to getting a 1/4" fuel line over a 1/4" hose barb? I have heated and oiled them and tried different brands of hose and fittings. It can't possibly be this difficult. What is the trick? I can usually get them half way on and no farther and end up having to cut the hose to get them back off to try again. What am I doing wrong or not doing right?