RV Repair: roof rot/soft spots, roof rot, liquid rubber

Question
have a j24 prowler, 1999, soft spots on roof around ac, roof is starting to sag. rubber roof, wood rafters. planning on doing this repair myself. need to know how to remove the ac unit, can i cut into the rubber roof to peel it back just far enough to see how much damage is done and then just roll it back after repair and patch, what do i patch it with. rest of roof is ok, its all around the ac unit.

Answer
Art, The air conditioner is mounted to the roof with 4 bolts that pinch it from the bottom. Take off the inner cover and you should be able to see them. If this is a ducted system there will be a plenum under the cover that will have to be removed. As for cutting the rubber and peeling it back to open it up for repairs, well the rubber is glued to the roof and when you peel it back you will stretch the rubber and this will make things harder. You would probably be better off if you remove the rubber and replace it with new. Even if it is just a 3 or 4 ft section that you remove. If it were me, I would pull the rubber all off and make the repairs and then put new rubber back on. The rubber for that shouldn't be more than about 400.00, which isn't much when it comes to keeping the rest from getting wet and rotting. If in fact you decide to patch remember that the manufactures recommend that you put dicor (carlisle) or Liquid rubber on the rubber. Anything else is not recommended. Liquid Roof by Pro Guard is what I would use whenever patching any roof, especially rubber. The main thing to remember is to get it cleaned right and etch the rubber with vinegar to make the liquid rubber attach better. I hope this helps, Bill