Leak as I sit in my 2021 Forest River 2860 DS Class C

[HiTech]

This is my 7th RV (3rd new Forest River in a row over the last 20 years), but first fiberglass roof.

It has an odd mix of what looks like self leveling Dicor and some clear sealant on the roof. Did an inspection a few weeks ago and other than a spot in back where it looked like the factory did not get the clear sealant on the entire seam by the ladder, it all looked sealed.

Sitting right now in Fort Wilderness in a heavy shower, the vertical support of the cabinet that the front cab over TV mounts to is dripping water onto the back cushion of the dinette.

I have Dicor and Eternabond with me. Also a small tube of silicone caulk.

Any suggestions on where to start on the roof?

[HiTech]

Update:

I pulled the Connexx radio (I had been planning to fix the factory miswiring of the outside speakers to the power-on-default A channel), and the rain seems to be coming down the FM coax wire. I have mopped up inside there and have a fan drying it out. Anyone know how to properly reseal the 360 degree antenna if that is the leak? The electronic manual application says it is a Winegard 360.

I pulled the plate for the amplifier with the splitter and coax in the cabinet. It is for sure dripping from above down the coax.

I am wondering if the proper sealant might be self leveling silicone sealant. This is my first fiberglass roof so I need to get all my supplies together to maintain it. Bought new in November.

[GL1800Rider]

I am not super knowledgeable on this subject but am fairly certain if you are going to caulk over what is already on the roof you want to use self leveling Dicor. Not the other that is silicone as it may not adhere to the original caulking. Make sure you get the corners in the front at the cap where water tends to pool and also the rear corners. That is where mine leaked. Sorry to hear you already have leaks in a new unit. Mine took 3 years with a lot of road miles on it.

Just looked at the hourly forecast and it appears you will have about 4 hours before it starts raining again.

[5picker]

If the other caulking is Dicor, DO NOT use Silicone. In fact, stay away from using Silicone anywhere on the outside of a R/V. Nothing will ever stick to Silicone in the future, including more Silicone.

Dicor, Alpha, Lexel, Geocel, and Pro Flex are my go to outdide sealants.

[HiTech]

These are the rules I followed on my previous RVs. I think there is a chance the self leveling caulk on this one may be self-leveling silicone. The cover of the Winegard 360 has a tiny part of one screw head exposed upon close inspection, and a hole where it looks like a screw should go not quite filled with sealant as well. I pushed the self-leveling sealant into these as best as I could. I have the stereo, antenna amp and areas right under the antenna dried out with paper towels, and a fan blowing up in there. If I knew Eternabond were ok to use on this roof I could easily cover both spots.

[Larry-NC]

I can't imagine why Eternabond couldn't be used. On our 2008 Cherokee, the skylights on the slideout are flat plates of polycarbonate (clear plastic sheet) held to the membrane with 3-inch wide Eternabond on all four edges. They never leaked. The sheets aged in the sun and broke. I replaced them with new Eternabond.

Searching Google for "Eternabond fiberglass" gets a bunch of hits. I didn't look at their details.

[HiTech]

Originally Posted by Larry-NC

I can't imagine why Eternabond couldn't be used. On our 2008 Cherokee, the skylights on the slideout are flat plates of polycarbonate (clear plastic sheet) held to the membrane with 3-inch wide Eternabond on all four edges. They never leaked. The sheets aged in the sun and broke. I replaced them with new Eternabond.

Searching Google for "Eternabond fiberglass" gets a bunch of hits. I didn't look at their details.

It seems (pun intended) to be related to whether the fiberglass is painted or not. Apparently not recommended on painted fiberglass.

[Larry-NC]

Originally Posted by HiTech

It seems (pun intended) to be related to whether the fiberglass is painted or not. Apparently not recommended on painted fiberglass.

Ah! That doesn't surprise me. Eternabond is pretty darn adhesive. Possible that it would pull the paint right off the fiberglass.

[camaraderie]

X2 on 5pickers silicone comment. NEVER use outside on anything!.
Most likely this one calls for dicor... BUT... if you are mounting something on fiberglass and need to keep water out... I would first use some butyl rubber doublesided tape...available at Lowes, Home Depot and online. this will make a flexible seal that will stay that way for years while allowing easy removal should the need arise. Then surround with Dicor.

[HiTech]

The Winegard 360 is directly above the leak. There is one spot where a screw is missing a little self-leveling sealant on one side. There is another hole where a screw could hold the 360 down but there is not one. It is only half filled with sealant. I think these are my leaks. I pushed sealant into the seams, and taped a trash bag over the whole dome until I can find out the proper self leveling sealant and get some.

[Wandering]

Good you found a likely source of your leak. I would stick with dicor on the roof. I put eternabond on all the seams of my fiberglass roof (2451s) and over the intact dicor. It been up there 4yrs and looks great. Enjoy Mickeys Place.

[HiTech]

I am a bit concerned about using Dicor. I have it on board. My factory fiberglass roof has clear sealant on it that looks like silicone caulk. Is has self leveling sealant on top of that in places that adheres tightly. I wonder if that is self leveling silicon instead of Dicor. The two are not compatible.

[camaraderie]

Originally Posted by HiTech

I am a bit concerned about using Dicor. I have it on board. My factory fiberglass roof has clear sealant on it that looks like silicone caulk. Is has self leveling sealant on top of that in places that adheres tightly. I wonder if that is self leveling silicon instead of Dicor. The two are not compatible.

If there was clear silicone caulk used by someone...Dicor is still the right choice BUT you need to do some prep.

First...silicone caulk remains flexible and rubbery. Does this match your roof surface in spots? Fiberglass roofs all have a gloss surface which it the gelgoat and CLEAR & HARD and on the whole roof. The gloss fades with time unless you are a fanatic...and I like the traction of a buff surface. Now if you DO have silicone that some idiot used up there...then you must scape as much off of your mounting area as possible and then use sanding products to remove what remains and get right down to the fiberglass surface. Clean any dust off and then wipe with acetone to insure a good surface for the Dicor to adhere to.

It works really well on fiberglass so no worries on that score.
Just as a side note...I've found standard plastic scrapers difficult to use removing silicone. Turning a piece of lexan into a scraper by cutting it at a 45 degree angle provides a more effective and sturdier tool. Works great on laquer/varnish prep too.

[HiTech]

Originally Posted by camaraderie

If there was clear silicone caulk used by someone...Dicor is still the right choice BUT you need to do some prep.

First...silicone caulk remains flexible and rubbery. Does this match your roof surface in spots? Fiberglass roofs all have a gloss surface which it the gelgoat and CLEAR & HARD and on the whole roof. The gloss fades with time unless you are a fanatic...and I like the traction of a buff surface. Now if you DO have silicone that some idiot used up there...then you must scape as much off of your mounting area as possible and then use sanding products to remove what remains and get right down to the fiberglass surface. Clean any dust off and then wipe with acetone to insure a good surface for the Dicor to adhere to.

It works really well on fiberglass so no worries on that score.
Just as a side note...I've found standard plastic scrapers difficult to use removing silicone. Turning a piece of lexan into a scraper by cutting it at a 45 degree angle provides a more effective and sturdier tool. Works great on laquer/varnish prep too.

Brand new from the factory. 2021 bought in November, just shipped from the factory. Mix of clear silicone and what looks like silicone rather than Dicor self leveling compound. It adheres very tightly to the clear. Nobody seems to have experience with this.

[5picker]

Are you sure the clear stuff is silicone?
The clear Geocel sealants (often used by Forest River) are not silicone.

When I called the factory about mine, they told me exactly what they used.

[Larry-NC]

Originally Posted by HiTech

Brand new from the factory. 2021 bought in November, just shipped from the factory. Mix of clear silicone and what looks like silicone rather than Dicor self leveling compound. It adheres very tightly to the clear. Nobody seems to have experience with this.

Time to contact the factory for a recommendation.

[HiTech]

Originally Posted by 5picker

Are you sure the clear stuff is silicone?
The clear Geocel sealants (often used by Forest River) are not silicone.

When I called the factory about mine, they told me exactly what they used.

Interesting. No I am not sure. Would be great if the leveler is Dicor up there. Then I just need a tube of whatever the clear stuff is.

[HiTech]

Originally Posted by HiTech

Interesting. No I am not sure. Would be great if the leveler is Dicor up there. Then I just need a tube of whatever the clear stuff is.

Anyone know the best way to contact the factory to find out what sealants to use on my roof?

[5picker]

Originally Posted by HiTech

Anyone know the best way to contact the factory to find out what sealants to use on my roof?

Have you tried the contact us page on Forest River's web site?

Go there, find your make R/V and click on it.
Each division has contact information associated with it.
Here's the link...

Forest River Contact Page

[Larry-NC]

Originally Posted by HiTech

Anyone know the best way to contact the factory to find out what sealants to use on my roof?

See the attachments. They are two years old, still should be helpful.