How would you seal this gap?

[mmzeiner]

I recently purchased a 17' Burro. As I've begun getting a good look at it, I've noted a gap on the underside of the trailer between the floor and the hull. Right where the floor sits on top of the lip of the hull, if that makes sense. I've attached a couple of photos. The gap is maybe 3/4" wide - I can easily slide my finger into it. The floor is not loose in this area - that is, if I go inside the trailer and press down on the floor, it does not "flop" or move to close the gap. I would like to make sure this gap is sealed/water tight before we hit the road.

What would you recommend to seal a gap of this size? Latex caulk? An expanding foam of some kind (Great Stuff, for example)? I worry that the volume of caulk necessary to seal this gap might not cure correctly - it wouldn't be a standard size bead. But are the expanding foams water tight?

There is one photo from each side of the trailer. Photos are taken facing forward, near the curve of the hull on either side. Hope that makes sense!

[BOBco.]

Not sure what I'm looking at and don't have a Burro but I bet those 2 parts are glassed together inside the trailer. Probably no need to do any thing. If the floor is broke loose from the body you would want to fiberglass it back together. Hopefully someone with a Burro will reply.

[mmzeiner]

Thanks Bob! To clarify, this gap only exists on the two front corners. The floor is nice and snug around the rest of the hull underneath. On the right side I can see daylight (a gap maybe 6 inches long) when I look into the space beneath the front seat. I do not see daylight under the left seat, but I haven't fully contorted myself under there to lift the reflectix away from the hull.

At some point in its history, this trailer experienced trauma in the form of a tire blowout that damaged a rear wheel well. I assume this gap in the front is related to the shock of the frame hitting the ground with force. There are some small cosmetic cracks in the hull near the tongue frame that are consistent with my theory.

[gage]

Maybe this advice will help. On one of my restores I had a gap of about a 1/4" by about 2" long between the floor and a wheel well. I filled the gap with expanding foam and for me it did the job. No water in on the floor from the tire. Went through a heavy rain storm and more water came in through the front window than the wheel well (like none).

[scotty61]

This reminds me of when I had to redo the front floor of an old car I had. It had rusted out. After removing the interior carpet, I took a piece of sheet metal, cut it to size, put down a coating of roof patch (waterproof and remains somewhat flexible), and the pop-riveted down the sheet metal. I then coated the rivets on both sides with tar, and then the underside of the car floor with more of the tar. What I'm thinking is that you could possibly pop-rivet the 2 pieces together after applying roof patch in between, and then again on the outside. Be sure to use large diameter washers on both sides, and, if possible, try to use stainless washers and rivets. You could then finish sealing the joint on the outside with the remaining roof patch.

[Perry J]

I would clean the area well and pump it full of silicone.
When cured it will be ridged to support any weak areas, will remain flexible, seal out any moisture and is in an area which will not create any refinishing problems in the future.
I know I will raise the ire of many by recommending Silicone but everything has it's appropriate uses.
John

[kirkman]

Is the gap where it gets full of dirt and water while driving or is it in the front? It does not look from you pics that there in any thing collecting in the gap now so why do you want to fill it with some thing that could pull lose and let water collect and rot your floor. Just my 2 cents. Is not rooting now I would just leave it be. When I had my Uhaul it had a similar gap and the floor was In great shape.


Sent from my iPhone using Fiberglass RV

[Jon Vermilye]

If you do decide to fill the gap, first choose the appropriate sized backer rod (an example) available at most hardware stores. Use it to fill most of the gap, that way you can use a thinner layer of caulk.

As to the caulk, I'd use anything but silicone. Once you put silicone caulk on anything, it is almost impossible to completely remove it if you change your mind or want to use something else.

[Perry J]

Originally Posted by Jon Vermilye

If you do decide to fill the gap, first choose the appropriate sized backer rod (an example) available at most hardware stores. Use it to fill most of the gap, that way you can use a thinner layer of caulk.

As to the caulk, I'd use anything but silicone. Once you put silicone caulk on anything, it is almost impossible to completely remove it if you change your mind or want to use something else.

If he cleans the area correctly and fills the void with Silicone he will not need backer rods as it is semi rigid yet flexible and will be their when any other caulking has deteriorated.
He will not have to change his mind.
Seven years ago I had a similar problem on a 13" Scamp which blew a tire and separated the wheel well and floor from the wall in the right rear corner
After a reglass job on the floor and wall inside I still had a gap which I filled with silicone.
I gave the Scamp to one of my kids and I know after 7 years it's still doing the job I intended it to do.
It also has not deteriorated as most any other type of caulking will.
Proper cleaning is the secret to the long adhesion life.

[Captleemo]

I think I would do like Gage says and fill the gap with expanding foam but I wouldn't stop there. After it has dried I would try a spray can of that sealant that you see on TV and looks to be readilly available at WalMart and use it to seal the expanding foam.

[Glenn Baglo]

It's always best to find out if what you are trying to fix was done intentionally or not; like a screw that isn't tight, so that the material it is in can flex and move.