Glue Question

I second the suggestion for an automotive adhesive. NAPA carries it in caulking type tubes.

I was in a TrueValue hardware a couple of weeks ago looking at plastic adhesives. They had one that says it will work on any plastic including polyethylene which is very difficult to glue. It is a two step system with a pretreatment that prepares the surface.
Might be worth taking a look at.

If you are sure it was glued in first place I would try automotive adhesive that is used to glue rubber weather stripping on cars. It's very strong and you can find it at most auto parts stores.

I suggest you call Coleman. They will know what the materials are and what should work. If they don't have an answer, ask what the materials are and then go looking for adhesives.

If the roof is ABS, this may be a trick, but it can still be done.

Matt