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jayspi's avatar
jayspi
Explorer
Feb 17, 2015

Replacing swollen wood on slide out bottom (outside)

Disclaimer: I'm a complete newb. This is my first RV. I have an issue that I want to try repairing myself, though. Here goes...

Note: The pics are here. The problem I'm concerned with are the ones on the outside bottom of the RV. I already had the dealer dry out and patch the wood on the inside corners (it wasn't rotted, just wet).

I recently bought a used 5th wheel and found that there is debris coming in one of the corners when I bring in and then retract the slide out (see attached pics). From what I can tell, the original problem was caused by water that was coming in the corner of the slide out. I had the dealership re-caulk that and dry the unit out. However, the problem now is that the undercoating in that corner got swollen from the water. Now, when it rains (and I live in the Pacific Northwest so at this time of year it's constantly raining) water runs down the side of the slideout and then runs underneath the underbelly, which is continually making the problem worse.

Now, I *could* take it back to the dealer but they did a pretty half-@#@ job the first time around. I know they won't repair it well since it's a used unit. So I want to fix it myself.

First step is to install a slide out cover, which I'll be doing this week.

Second step is to put some sort of lip on the bottom of that side of the slide out to keep condensation from running under it in the future (I found some good Youtube tutorials on that).

The THIRD step, and the one I have questions about, is how to patch the bottom of the slide out so that it doesn't keep dragging debris in with it.

I contacted the dealership and this is what they suggested: "A suggestion would be to get what’s called belly rap tape that comes in 4 inch width. You can use that to cover the area where the corners are or even go the whole length of the underbelly of the slide just to make sure.. The area would need to be dry in order to do this and the wood sprayed with undercoating. "

So that raises two questions for me. First, what does he mean by "spray the wood with undercoating"? I did some research and can't find anything that relates to that.

Second, after I've put on said undercoating, what type of belly wrap tape do you guys recommend? Searching around on Amazon leads me to the "Flex Mend Underbelly Repair Tapee", but I have no idea if that's what I need or not. It seems to be more for repairing the underbelly of a unit, not for patching wood.

Thanks in advance for any tips!

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