you are looking for even more disaster using oil - twice the work and a pain if you have to strip it - I would stay with latex for sure but your method or the type of paint you are using is wrong - make sure you get out door paint for decks - Bahr, Expression - they all come with good outdoor deck paint in many colors - make sure the deck is nice and dry - old paint is removed and paint it with roller or brush when it is cloudy or in the evening - not in direct sunlight - two coats should last you 3 to 5 yrs - good luck - if you need more info email me