I know I'm late on this threadů
I had the same problem as everyone else fitting sanitary lines. I tried all the same things mentioned here. Finally, while at WM I asked
and they sold me this stuff:
WEST MARINE Hoselube at West Marine
When I used it the hose slipped on without any effort
. Now, I keep a bottle on the boat at all times. Works great with the heavy duty ribbed bilge pump lines too!