Community Forums

SyrenSkywolf · 04-26-2012, 08:41 PM

A few weeks ago, I discovered a leak in our motorhome right before we left on a trip (without the rv). It was raining the whole time, so I couldn't do much about it. When we got back from the trip, the weather was so nice I completely forgot about it until last night when it started pouring out. The leak was terrible.

I remembered my investigation in the rain from the first time, and today did some more looking to make sure. I have found, with almost complete certainty, the water was coming down the inside of the outer wall next to the steel/insulation framing, and when it hit the window, came inside. It comes in the top of the window, almost in the center, and drips down.

The reason I know this, is last fall I installed rain deflectors over a couple windows, as rain liked to seep into the lower track on its way from the roof, and wouldn't drain fast enough. The deflector is completely sealed on top with sealer, and when I look under it between it and the window is completely dry. I also know how the roof underneath the aluminum sheet is designed, and know water couldn't leak in elsewhere and run to the edge. There are a few other things, but I will leave it at that.

Today, I took my eternabond and went to town on that section of the roof. It is completely sealed there. I ran it along the top of the trim over about 3-4 inches on the roof, even sealing around the cargo rack tubing. Upon returning home this evening, in the rain, I noticed it is still leaking! Granted, it is nowhere near as bad, but still leaking nonetheless. It has gone from a steady drip last night, to a drip ever 5-6 seconds. I am at a loss as to where it could be coming from now.

Any ideas or suggestions on this? Could it be getting in the trim and seeping in past a screw?

To show the deflector:

greystroke · 04-26-2012, 09:15 PM

My 5th wheel had a lot of leaks and by the time I found out where it was entering I had serious damage to my slide rooms. Very mystical.

Water fines a way to get in ...period. It does not necessarily come straight down. It could travel 6 or more feet horizontally in the RV before it starts down.

Mine seeped in like ink to a blotter. Entered one side and damaged the other side.

First search for soft spots in the roof and repair it. Seal the whole roof not just places where you think it is leaking. Use dicor sealant everywhere. You can re-coat the whole roof with coatings from CW or other RV supply house. Sometimes it is very hard to see water entry points in the roof so just take the roof out of the equation and seal it. Make sure skylights, and roof openings of ACs and vents are also sealed. If the sealant has cracks around these areas re-do it. You will probably feel soft spots in the foot at entry points. Remember the blotter effect.

On both of my trailer slides the water come down the outside and then at the bottom the water flow turned the corner and seeped int to flooring. The entry points had no sealant at all. The mfgr just missed it.

Good luck

Then work on the sides.

az bound · 04-26-2012, 09:17 PM

Since you have sealed everything else I would suspect its at the window itself. More than likely the butyl seal where the window frame meets the exterior wall.

sam-3 · 04-26-2012, 09:43 PM

God advice from the previous poster to work on the roof. Take out the window and then you will see the inside condition of your wall. If the wall is wet you will have to tearout wall paneling,luan. The biggest mistake I see being done is ripping out walls to the studs and putting in luan and new paneling. What is not being done is coating the fiberglass or alum with bondo/2part epoxy. This gives a hard coating to seal up any pinpoint holes you can't see. Reseal your window with butyl tape on the round part. Clean off the exterior wall with googone and dry. Rinsery window and use a butter knife to cut off any excess butyl tape. Then apply around the window/exterior Lexell caulk or silka a. You can get at ace hardwear or on the internet. I know you have already done extensive restoration. Don't be afraid to use lexell caulk after the bondo dries on all ffour sides of interior wall . Leave the wall open after bondo and caulk. Wait for a rain storm to see if you need additional caulk or foam spray. We had to beef up our open walls with caulk,foam after a rainstorm. You will see pictures of our restoration on page 3. 2-29-2012 Restoration of 1990 Classic HiLo. We finished our restoration in Jan 2012 and we have remained Hi and DRY. I know my picture descriptions are hard to read as they are in red ink. I am challenged with my limited computer knowledge. We don't consider ourselves expert with rv restoration,but this is what worked for us. We were blessed to be given good advice by two good sources and this is why are our repairs have held up. Best of luck in your repairs. Post again and let us know if your were successful in getting your leak under control.

sam-3 · 04-26-2012, 09:48 PM

It is amazing how far water can travel and do dammage.You will need a respirator to put on the bondo and to have all windows and vents open. You will have to spend a few days away from the Rv until the smell clears out.

Midniteoyl · 04-26-2012, 10:07 PM

Pour water on your roof and see which way it flows.. then look 'up stream' for your leak.. Water gets in, hits the wood and flows downhill until it hits a seam. Then it flows on top of the foam insulation until it finds its seam. Or the outer wall..

SyrenSkywolf · 04-26-2012, 10:14 PM

Thank you all for the advice you gave, but very little of it pertains to my situation.

As said, it isn't the window, and it is NOT traveling along the roof then dropping down. The design of the roof under the aluminum would cause it to leak elsewhere, not at the window the way it does. And, it has a steel frame, so I have very little wood to concern myself with.

I have done extensive work to this motorhome, which is why I know how it is designed, and why I am baffled by this leak, and hoped to turn to everyone here for some insight.

RV Wizard · 04-27-2012, 02:20 AM

I have seen water wick (travel up hill) to another area before falling. This make it nearly impossible to find and repair. I would suggest getting it to someone that has a duct blower type machine (we use a SealTec) that can pressurize the interior of the coach and with soapy water on the outside; find leaks.

az bound · 04-27-2012, 06:29 AM

Another leak that is quite common is the ac unit mounting bolts have loosened.

sam-3 · 04-27-2012, 09:37 PM

My trailer has steel frame in it.

Driven1 · 04-29-2012, 07:28 AM

I suspect either the corner trim or the ladder mounts on the roof. Had a heck of a time with my ladder mounts. Leak would go from them back through the roof underlayment a bit and then down into a closet. Capillary action can make water go just about anywhere depending on the underlying construction. Might be traveling from either of those areas across the top of the inner window framing. Good luck! Leaks suck.

Greyeagle · 04-29-2012, 08:21 AM

Since you know where it's not leaking might want to look at the other places it could come from IE other side, AC, vents, ladder contacts, skylight, fridge vent, front and/or rear cap seams, any seams on roof, cracks etc.. Best of luck in your search........

oldbeek · 05-01-2012, 10:03 PM

X2 ON THE AC UNIT. Pull it and look. $ 17.00 for new seal. Mine was installed wrong and did not leak till 16 years old in Alaska. %6 days of rain. Water was dripping 4 feet from AC unit.