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daystrom's avatar
daystrom
Explorer
Oct 13, 2013

Leak, my homemade Sealtech attempt, & question

Got a small leak in a front cabinet of my trailer. Happens during a windy rain or while driving through rain. Just a normal rain and nothing. Slow drips from the same area. Cap seal looks great, and leak appears right behind the marker light.

I can simulate a driving rain by focusing a garden hose on the front right side/roof and within a minute a get drips inside the closet. The leak is most likely very close to the right front corner.

So I made my own Sealtech machine with parts from Harbor Freight.

1600 CFM ventilator



16' 8" diameter duct



8" galvanized duct (from Lowes)




I made a base for the galvanized duct out of OSB and traced the vent beauty ring matching the screw holes so I didn't have to make more holes in the ceiling.

I sealed the galvanized duct as best I could:



And attached it to the ceiling:



Next I attached the 16' long duct:



My wife bought the local Walmart's stock of kids bubbles which I sprayed on using a small pressurized sprayer.

I powered the system up and sprayed the area in question with bubbles. No sign of leaks. I sprayed areas around the door where I knew would leak and nothing. Not enough pressure inside.

Problem 1: If you look closely you can see daylight coming through the galvanized piece.

Problem 2: The orange 16' duct really cuts down the volume of air. The blower itself can really move some air and is well built.

I ended up pulling the marker light off to inspect:



There was no sign of water behind that light however I stuck my finger up inside that hole and did notice moisture. I also found that Crossroads overlaps the rubber roof to almost the marker light and the small amount of water would run down the rubber roof tucked away under the aluminum skin.

As I said above the cap seal looks great. I am ANAL about inspecting this seal. I ended up going down to my local RV store who was out of ProFlex but offered some OSI Quad (which was pretty easy to use compared to ProFlex). I resealed the corner molding on both sides, and the area where the gutter meets with the drip extension.

Re-ran my rain simulation and no drip, even after 20 minutes of heavy rain simulation so I think I may have gotten it.

So my question is to those who have gotten a real Sealtech test done, do the dealers get any attitude when you just want the test done so you can patch at home? A dealer about 45 minutes away wants $99 for the test which is about what I have in parts for my homemade machine...too bad it didn't work. At least I can return the blower and duct.

I am OUT of the two year warranty so that isn't an option. Trailer was purchased in 2011 but is a 2012 model.

Thanks for reading!

Todd
  • I'm happy to report that blowing air into the trailer was a success. I fabricated piece of thick cardboard the size of the baggage door and cut out an 8" hole for the concrete form. Luckily I had an 8" form in my garage so no trip to Lowe's was necessary.



    Duct tape was used to seal up the door/cardboard and the form to the fan. This combination produced a lot of air in the camper. The entry door was being held open 2" by air.

    I'm happy to report no leaks other than areas I knew would like the range hood vent, outside shower, and electric cord hatch.







    Version 2 I'm hoping to use some plywood and build in a manometer.

    Thanks everyone.

    Todd
  • daystrom wrote:
    Thanks Westend. Great post and pics. Gives me something to try now.

    What kind of leak test liquid did you use. If you made your own what was the soap to water ratio?

    You're welcome. I used an empty Windex spray bottle, added water until nearly full, and pumped 6 pumps (or so) of Dawn dish soap into the bottle. You could probably add glycerin or corn syrup for a stronger bubble but it isn't necessary and the soap and water cleans up easily.

    When I did my first test, I blocked off the vent openings and small jalousie windows with foam board. I forgot about the heater vent and didn't seal the door, probably a good thing as just an inch of water column is plenty of pressure.

    My rig is very well sealed with multiple vapor barriers and I had sealed the siding to the framing around all the openings, including the wall to roof joint. That joint is also sealed on the roof exterior with Eternabond tape. The roof had zero leaks but I discovered about 20 pinholes in various places around the siding. I filled those spots with Geocel Tripolymer 2300 caulk and retested again, I had no more leaks. I made a location map of the leak locations on five sheets of paper so that I could remember where they were after the testing.

    I plan to do this test at least once a year. It's easy to do and should help keep my rig sealed.
  • I did the same with an old furnace blower. I went through a pass through cargo door.



    The first time I did the test, I found so many leaks I recaulked the whole trailer. I used Eternabond on all the roof seams. I just rechecked it this year and was good to go.

    As far as soap, I used water with dish soap and baby shampoo. Not sure about proportions, but bubbles will show up.
  • Thanks Westend. Great post and pics. Gives me something to try now.

    What kind of leak test liquid did you use. If you made your own what was the soap to water ratio?
  • I would suggest you try to blow the air into the cabin rather than pulling it from the inside. You could probably reverse the vent mount and attach the blower to the hose, outside, and get sufficient pressure, blowing in to pressurize the interior.

    I used a squirrel cage furnace blower mounted to a window. I drilled a hole in the plywood mount to accommodate a 1/2" plastic tube. The tube is part of a DIY manometer that will show how many inches of pressure are being developed. The Sealtech system develops about .5 in. of differential. My squirrel cage blower measured 1" differential or more.





    A pin hole leak discovered using dish soap and water:



    Good luck with your leak fixing, it sounds like you might have found the biggest one.
  • I've seen that too and was plan B but couldn't figure out how to connect the blower to a box without loosing air.

    EDIT:

    Something like this would work perfectly:




    8" concrete forming tube
  • I have only seen one device to pressurize the inside and it was a box that sat over the roof vent and was powered by a leaf blower. Glad you found the leak