Under carriage question

[Socaldave]

Previous owner had a blow out and it caused some damage to the fender skirt and took some of the undercarriage material off. it looks to just be the sub-floor under that webbed stuff and only obvious traveling in wet weather that wood is going to wick things up. What should I re-seal this area with?

[wiredgeorge]

Originally Posted by Socaldave

Previous owner had a blow out and it caused some damage to the fender skirt and took some of the undercarriage material off. it looks to just be the sub-floor under that webbed stuff and only obvious traveling in wet weather that wood is going to wick things up. What should I re-seal this area with?

Perhaps a tape specifically made to repair that torn part underneath your camper:
https://www.amazon.com/underbelly-Ma...jaz10cnVl&th=1

[JRTJH]

I'd be willing to wager that there have been more "destroyed floors in travel trailers" from wet/damaged wheelwells than from any other "my entire floor is soft and molded" complaints.....

What you have in your wheelwell is the root cause for Keystone to have opened an entire facility to rebuild trailer floors in both the Oregon and the Indiana facilities.

Whatever you do, don't get caught towing that trailer in a downpour, or even on a slightly damp highway. It would be the "ticket to destroy your trailer" !!!!!

I used heavy plastic wallboard (1/4" thick) cut to fit my wheelwells, sealed it to the remaining DARCO film, screwed it into place through the trailer frame/subfloor, and then sealed the entire perimeter of the plastic sheeting. It's been in place about 4 or 5 years now and seems to be holding up well. That said, I haven't had a tire blowout, and would expect something like that to "rip hell out of anything/everything I did to protect my wheelwels"....

But, my main message to you would be, DON'T put that trailer on the highway before you repair/seal that area. If you do, and get caught towing in the rain or on a wet road, you're going to set yourself up for lots more headaches than you'd imagine.....

[sourdough]

As was said, don't get caught on a wet roadway with that or you will cause yourself a lot of grief.

I can't tell from the pic but is/was there any type of insulation above that? If so you need to replace that. You could use something like in this link;

https://www.amazon.com/Mobile-Flex-M...80919658&psc=1

Make sure whatever you put in/up there is adhered well. If you don't have one I'd get a can of spray adhesive to glue it down. No matter how you repair it I would then cover the tops of the wheelwells with a liner of some sort. I've got pieces of uhmw cut to fit over my 4 tires but haven't found (took) the time to put them in. That darco IMO should never have been put on the bottom of a trailer and especially not over a tire that will send up gravel and perforate it in no time.

[dutchmensport]

Spray paint the dickens under there with an oil based paint, like original black Rust-o-lium, and attempt to spray paint under the fabric. Let it dry real good. Then use Eterna bond tape and cover it all up. Do it when it's NOT raining!

But if the tire rubbed once, it will probably do it again. So, in addition to the paint and tape, you could lay a sheet of metal there, cut to fit the area, then screw and secure it to the wheel well, so if the tire rubs again, it will rub the sheet metal and not the wood.

If it were mine, that's what I'd do. Sounds easy, but may be difficult to do unless you remove the tires.

[Socaldave]

Yeah looking at it initially I was like WTF but then realized the details that go into the build of one of these High end TT...LOL. I've owned other campers/fith wheels and seems 90% as built are sub par. I've got a repair plan for both sides and will share it once i get my materials.

[bsmith0404]

Personally, I’d use the underbelly tape and then spray it with undercoating, the kind of stuff the use on car frames and fender wells. You can buy it any any auto parts store. It’s nasty stuff if you get it some where you don’t want it….wear gloves.

[sourdough]

The problem with the undercoating spray put over glued on darco is that the darco will let go from whatever it is glued to. I've seen that happen. Darco is so flimsy and then the weight of the undercoating just pulls on it until it lets go it appeared.

[JRTJH]

Originally Posted by bsmith0404

Personally, I’d use the underbelly tape and then spray it with undercoating, the kind of stuff the use on car frames and fender wells. You can buy it any any auto parts store. It’s nasty stuff if you get it some where you don’t want it….wear gloves.

The problem I see with spray undercoating in this application is the photo that the OP posted in his first post shows that the DARCO is no longer adhered to the wood subfloor. So, spraying the DARCO is only as good as the DARCO lasts. It will flex and where there's a crack or crevice, once the spray undercoating pulls away from the DARCO, water will seep into the subfloor.

It's sort of like applying new wall paper to a wall where the old wall paper is falling off the wall. The only thing that holds the new paper is its own strength. Once it cracks or once the old paper under it fails, the entire thing falls down.

[bsmith0404]

That’s why I said to use the underbelly tape first. It’ll stick to the wood and hold everything in place. I guess I should have also specified to only spray a light coat around to make sure there isn’t any air gaps where water could get in.

[JRTJH]

Originally Posted by bsmith0404

That’s why I said to user he underbelly take first. It’ll stick to the wood and hold everything in place. I guess I should have also specified to only spray a light coat around to make sure there isn’t any air gaps where water could get in.

Not sure exactly what you're saying in the first sentence, but I think it's for the OP to put underbelly tape on his wheelwell first, then spray that with undercoating ???? That would be putting a third layer of wallpaper on the old stuff that's falling off the wall...

Anything worth doing is worth doing correctly. Putting tape on loose DARCO and then spraying that with automotive undercoating is just throwing good money at a bad situation. When the DARCO pulls off the subfloor more than it already is, there's nothing for the underbelly tape to stick to.

[bsmith0404]

Originally Posted by JRTJH

When the DARCO pulls off the subfloor more than it already is, there's nothing for the underbelly tape to stick to.

Ummmm, the subfloor……it’s exposed. It’ll actually help hold the DARCO up as well.

[JRTJH]

Originally Posted by bsmith0404

Ummmm, the subfloor……it’s exposed. It’ll actually help hold the DARCO up as well.

The rest of the DARCO is falling off the subfloor. Take a look at the photo. There's no way in heck that putting tape on DARCO that's not adhered to the subfloor is going to somehow improve adhesion where there is none....

I'm done trying to explain the obvious. The OP can choose whether to do it correctly or patch the patch and hope it holds through the next trip. His choice, not mine or yours....

Side out.....

[slow]

On my 2015 Passport, the Darci was not attached in any way to the subfloor other than a few staples around the perimeter, rather it was draped over the sub floor.

SocalDave, this thread about my floor challenges may provide additional insights that may help you move forward with your repair: https://www.keystoneforums.com/forum...ad.php?t=23809

I used FlexMend tape to close the openings I cut to dry out the underside of my floor. I took a great deal of care to clean the Darco well prior to applying the FlexMend tape to the Darco under my trailer and the 6" width provided ample adhesive contact area. During the next three seasons we owned the trailer, we had no separation of the FlexMend from the Darco or water entry.

I purchased the tape from a local mobile home dealer, but it is readily available online. I choose to use 6" wide tape, but note that the FlexMend is also available in sheets which may be better for your situation given the size of the hole.

BTW: IMO, do not undercoat the FlexMend repaired area or any of the Darco. There is no need to.

[bsmith0404]

Originally Posted by JRTJH

The rest of the DARCO is falling off the subfloor. Take a look at the photo. There's no way in heck that putting tape on DARCO that's not adhered to the subfloor is going to somehow improve adhesion where there is none....

I'm done trying to explain the obvious. The OP can choose whether to do it correctly or patch the patch and hope it holds through the next trip. His choice, not mine or yours....

Side out.....

No reason to get hostile. I’m looking at the pic, the only place the DARCO appears to be pulled away from the subfloor is along the edge where the hole is. Putting underbelly tape over that hole (the tape is 6” wide) the tape will stick to the subfloor, will also stick to the DARCO and keep it from getting worse along the edge where it’s torn. The tape isn’t going to improve the adhesion of the DARCO, it’s going to stick to the subfloor and keep the DARCO from getting worse. So I guess I’m not seeing the “obvious”. I don’t think you’re understanding how I’m saying to do the repair, but it doesn’t matter. As you say, it’s not your choice or mine how he makes the repair.

[bsmith0404]

Originally Posted by slow

On my 2015 Passport, the Darci was not attached in any way to the subfloor other than a few staples around the perimeter, rather it was draped over the sub floor.

That’s the way they all are, at least from what I’ve seen. I’m not sure what the other guys are talking about. The main thing here is to get the hole patched so water can’t get up under it.

[sourdough]

My last RV had a section glued to the subfloor. The wheel well above the tire that blew out on that one had insulation above the darco. I knew I had a blowout when I saw all the white fuzz come flying out in the rear view mirror (didn't have a tpms then).

What is there or isn't is really irrelevant. Darco is a substandard material (IMO) that has no business in a wheel well. It cannot, and will not, withstand the constant impacts of road debris and gravel - it WILL get permeated which then explains all of the problems with soft floors.

Until I get the liners put in my wheel wells I will not, and have not, traveled on wet days. I don't "think" the lining will get wet, I know it will. Trying to cover that hole with some stick on darco doesn't gain a thing other than delay the inevitable, again IMO.

[bsmith0404]

Originally Posted by sourdough

My last RV had a section glued to the subfloor. The wheel well above the tire that blew out on that one had insulation above the darco. I knew I had a blowout when I saw all the white fuzz come flying out in the rear view mirror (didn't have a tpms then).

What is there or isn't is really irrelevant. Darco is a substandard material (IMO) that has no business in a wheel well. It cannot, and will not, withstand the constant impacts of road debris and gravel - it WILL get permeated which then explains all of the problems with soft floors.

Until I get the liners put in my wheel wells I will not, and have not, traveled on wet days. I don't "think" the lining will get wet, I know it will. Trying to cover that hole with some stick on darco doesn't gain a thing other than delay the inevitable, again IMO.

Don’t disagree with really anything you said other than the fact that underbelly tape isn’t stick on DARCO, it’s not a clothe material it’s more like a big piece of duct tape. I would actually compare it more to what they call the 100 mph tape they use in NASCAR to fix the cars after a crash and hold the body together to finish the race.

[Socaldave]

Okay guys, appreciate all the great feedback on this one.
I have decided to line the underside with either of the two products I have access to at work and no cost for materials other than I may need more Dicor to seal the edges once installed. More than likely going with the .250 HDPE. I'll provide pics of the install when it goes down...err should I say up.

[chuckster57]

Be careful using Dicor to seal the edges, since it never really hardens it may gum up the seals. I would use Proflex or another RV rated silicone sealant.