FOREST RIVER SUNSEEKER – Roof Leak Repair and Resealing

Roof Leak Repair and Resealing for FOREST RIVER SUNSEEKER

I’m on top of a Sunseeker right now with my hands in a delaminated seam, and what I’m looking at is textbook for this model: the factory sealant cracked somewhere around mile 30,000, water got behind it months ago, and now the plywood substrate is soft enough that I can push my finger through it near the AC unit. This is how most people discover their roof problem—not during a routine inspection, but when the ceiling sags or they smell mold, which means the damage is already deep. The reason I attack Sunseeker roofs first on any flip is that I’ve learned to think sideways about how these failures cascade. One cracked seam isn’t just one seam; it’s a pathway that lets moisture work its way into the walls, the cabinetry, the structural bones of the whole rig. By the time you notice wet spots on the interior walls, the decay underneath has usually been happening for months. I’ve stripped enough of these rigs down to know exactly where the breakdown happens and how to stop it for real, so here’s how I diagnose, prep, and seal these roofs so the repair actually holds instead of just postponing the problem until next season.

Required Parts

• Dicor Self-Leveling Lap Sealante Dicor 501LSW-1 Epdm Self-Leveling Lap Sealant-10.3 Oz. Tube, White, 10.3 Fluid_Ounces (Packaging May Vary)
• Eternabond RoofSeal Tape0 EternaBond RoofSeal White 4″ x25′ MicroSealant UV Stable RV Roof Seal Repair Tape | 35 mil Total Thickness – EB-RW040-25R – One-Step Durable, Waterproof and Airtight Sealant
• Rubber roof cleanern Dicor RP-RC-1GL Deep Cleaning Rubber RV Roof Cleanser Spray Refill – White, 1 Gallon

Step-by-Step Instructions

Step 1: Leak Detection and Documentation

Water infiltration on Class C rigs like the Sunseeker tends to hide until structural damage is already baked in, so catching it early and getting the diagnosis right saves you from much bigger repair bills down the line. Start your investigation inside the rig during rainfall or right after—check every ceiling corner, light fixture, overhead storage, and especially the spots around roof vents and AC units where penetrations create natural weak points. Hunt for water stains (tan or rust-colored marks), soft or spongy ceiling sections when you press on them, wallpaper or fabric that’s peeling or rippling, actual dripping water, or that distinctive musty-mold smell that tells you moisture has been trapped in there. Get a flashlight and peer into the backs of overhead cabinets and around light fixtures where water love to hide. Take photos of every spot you’re suspicious about and sketch out a quick reference map showing each possible entry point. Keep in mind that water doesn’t always drip straight down—it tracks along the roof structure and can pop up on the interior several feet away from where it actually got in, so the wetness you see isn’t necessarily where the hole is.

Step 2: Exterior Roof Inspection and Preparation

Pick a day when it’s dry and the temperature sits somewhere between 50-90°F—you need stable weather so your sealant can cure properly. Use a ladder with stabilizer bars and take your time; never work on a wet roof or when the wind is up. A Sunseeker roof is usually covered in rubber (EPDM or TPO), and you can walk on it but you’ve got to respect it—soft shoes, no sharp tools pressing into it unless you mean to fix something. Work methodically from front to back, and look hard at every place something sticks through the roof: AC units, roof vents, plumbing vents, antenna brackets, ladder feet, and that front cap where the fiberglass overhang meets the rubber membrane. Examine every seam you can see, checking whether the sealant is cracked, gapped, pulling away, or has turned brittle and chalky. Use masking tape to flag every problem spot so you don’t miss any during the actual repair work.

Step 3: Cleaning and Surface Preparation

You can’t glue new sealant to a dirty surface and expect it to last—adhesion is everything, which is why prep work makes or breaks the whole repair. Grab a dedicated rubber roof cleaner (Dicor RP-RC-1GL works), and scrub out the entire area around each problem spot, going at least 6 inches beyond the damaged sealant in every direction. Follow what the label says—usually you brush it on, let it sit for 5-10 minutes to eat through oxidation and road grime, then rinse it clean with fresh water. If there’s stubborn old sealant that’s got to come off, use a plastic putty knife (never metal—metal tears the membrane). Let everything dry completely before touching it with new sealant; that usually takes 2-4 hours depending on temperature and how humid it is. Any moisture left behind will sabotage your adhesion and blow up the repair.

Step 4: Removing Failed Sealant

Where old sealant has come loose or given up entirely, you have to strip it down to bare roof before you can lay new sealant over it and get a solid bond. With a plastic putty knife or a sealant scraper tool, work carefully and slowly to lift away all the dead sealant, taking care not to gouge or puncture the roof underneath or the fixtures you’re trying to seal. If the old sealant has hardened into concrete, an RV-specific adhesive remover can soften it up so it peels away easier—but test it first on a hidden spot to make sure it doesn’t eat your roof material. After the old sealant is gone, run the roof cleaner through the area one more time to wipe out any oily residue left by the old material. If you find tears, holes, or sections of the membrane that are falling apart while you’re working, those need Eternabond tape before you even think about new sealant.

Step 5: Applying Eternabond Tape to Damaged Areas

Eternabond RoofSeal is a heavy-duty, stick-down tape made for patching roof membrane damage, and it’s the thing that saves you when you’ve got actual tears or soft, degraded spots. For any crack, puncture, or area where the membrane is compromised, tape goes down before sealant. Cut the tape to cover the damage plus 2 inches of good roof on all sides—4-inch-wide tape handles most repairs without overkill. Peel back about 2 inches of the backing and stick the tape down exactly where you want it, then press hard. Keep peeling the backing back while you press the tape down as you go, working end to end so you don’t trap air pockets underneath. Once it’s in place, take a J-roller or a hand roller and press the whole thing down firmly and evenly, paying extra attention to the edges since those are where it wants to lift back up.

Step 6: Applying Lap Sealant to Seams and Penetrations

Dicor self-leveling lap sealant is engineered specifically for RV roofs and it stays bendy through the temperature swings that happen constantly—from freezing at night to baking in the sun the next day—so it won’t crack and fail like rigid sealants do. Load a tube into a quality caulking gun and cut the tip at 45 degrees to make a 3/8-inch opening. Start with the roof vents and work around the base of each one, laying down a full circle of sealant that overlaps any existing good sealant by at least half an inch. Don’t be stingy with it—a proper bead is about 1/4 inch thick and 3/4 inch wide. Keep steady pressure on the trigger for even flow and work all the way around each penetration. On the AC units, don’t forget all four corners where the box sits on the roof—those corners are leak factories.

Step 7: Sealing Roof Seams and Final Inspection

Sunseeker roofs are made from rubber sheets that get seamed together lengthwise, and those factory seams can handle weather for a few years before the sealant in them starts to fail. Run lap sealant down the full length of each seam, making a bead wide enough to cover the seam itself plus about an inch on each side. Pay close attention to spots where seams meet or where they end, because those junctions are weak points. Don’t skip the front—where the fiberglass cap meets the rubber roof is a high-movement zone that takes a beating while you’re driving, so it needs a thick, flexible seal. Once the sealant is down, step back and eyeball your work from different angles, looking for gaps, thin spots, or bubbles you missed. Self-leveling sealant will flatten out over 24 hours, but stay off the roof and don’t drive until that curing is done. Plan to check and re-seal annually if you want this roof to stay dry.

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The Sealant That Actually Stays Put on Forest River Sunseeker Roof Seams

Forest River Sunseekers are notorious for roof seam failure—the factory sealant dries out, cracks, and water finds every micro-gap on its way into the interior. Dicor self-leveling sealant is the only product that bonds to existing EPDM rubber without lifting or peeling, which matters because these roofs have already failed once.

What works

• Flows into seam gaps without you having to force it—levels itself as it cures, so you’re not chasing sealant with a caulking tool for an hour.
• Stays flexible after cure instead of becoming a brittle ridge that cracks the moment thermal expansion happens (which it will, constantly, on a roof).
• Actually adheres to old, weathered EPDM without primer—tested this on rigs that had already failed twice before I touched them.

What doesn’t

• One 10.3 oz tube barely covers a full roof seam re-seal—you’ll need 2-3 tubes depending on how much rot you find underneath once you start digging.
• Cure time is 24-48 hours before it’s truly waterproof, and you can’t speed that up—if weather rolls in or you’re on a deadline, this repair doesn’t compress.

I’ve had moments where I applied this over what I thought was clean EPDM, only to find the sealant wouldn’t set properly because moisture was trapped underneath—turns out a full chemical cleaning pass is mandatory, not optional. That’s when I learned to never skip the prep. Grab the Dicor 501LSW-1 Epdm Self-Leveling Lap Sealant-10.3 Oz. Tube, White, 10.3 Fluid_Ounces (Packaging May Vary) and plan on restocking once you see how much seam you’re dealing with.

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