Hi, as mentioned above use a black sealant make sure its Poly U. and not silicone based. I would recomend "tiger seal". Pull back the rubber and inject sealant along area of leak with roof in raised position. Repositioning rubber and again closing roof will provide force to squeeze out excess. excess should be wiped away with white spirit soaked lint free cloth, this will give you a perfect result, white spirit is important as if allowed dry it will require a scalpel to remove excess.